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4 - Excalibur Engineering

1. Enter Chapter 2 Front Panel Menu Operation To turn off the comma separator To turn off the comma separator The function generator can display values on the front panel with or without a comma separator The following steps show how to turn off the comma separator 15 000 000 MHz 15 000000 MHz With comma separator factory setting Without comma separator Turn on the menu A MOD MENU Move across to the SYS MENU choice on the MENUS level D SYS MENU Move down a level and then across to the COMMA command 5 COMMA Move down a level and then across to the OFF choice Save the change and turn off the menu The comma separator setting is stored in non volatile memory and does not change when power has been off or after a remote interface reset 91 N Features and Functions Features and Functions You will find that this chapter makes it easy to look up all the details about a particular feature of the function generator Whether you are operating the function generator from the front panel or over the remote interface this chapter will be useful This chapter is divided into the following sections e Output Configuration starting on page 55 e Amplitude Modulation AM starting on page 71 e Frequency Modulation FM starting on page 76 e Burst Modulation starting on page 81 e Frequency Shift Keying FSK Modulation sta
2. M35 X 0 6 4 PLACES All dimensions are shown in millimeters 301 302 Index If you have questions relating to the operation of the function generator call 1 800 452 4844 in the United States or contact your nearest Agilent Sales Office CLS command 209 ESE ESE command 209 ESR command 209 IDN command 113 190 OPC OPC command 166 173 210 PSC PSC command 210 RCL command 153 RST command 171 190 SAV command 152 SRE SRE command 210 STB command 210 TRG command 173 187 TST command 190 WAI command 166 173 210 34398A Cable Kit 197 34399A Adapter Kit 196 F F HF X A ac line voltage fuse 16 selecting 16 ac signals attributes 283 adapters RS 232 196 address GPIB 114 217 Adrs annunciator 5 AM annunciator 5 AM modulation carrier frequency 72 carrier waveshape 72 example program 252 external modulation 75 156 front panel operation 41 modulating frequency 74 155 modulating source 75 156 modulating waveshape 73 155 modulation depth 74 155 operational overview 154 rear panel terminal 75 155 sync signal 74 technical description 287 AM DEPT command 155 AM INT FREQ command 155 AM INT FUNC command 155 AM SOUR command 156 AM STAT command 156 amplitude and output termination 60 149 arb waveform limits 148 177 conflict with function 59 149 front panel selection 20
3. FSKey FREQuency lt requency gt MINimum MAXimum Set the FSK hop frequency Select from 10 mHz to 15 MHz 100 kHz for triangle and ramp The default is 100 Hz MIN 10 mHz MAX 15 MHz Stored in volatile memory FSKey FREQuency MINimum MAXimum Query the FSK hop frequency Returns a value in hertz FSKey INTernal RATE rate in Hz MINimum MAXimum Set the rate at which the output frequency shifts between the carrier and hop frequency FSK SOUR INT only Select from 10 mHz to 50 kHz The default is 10 Hz MIN 10 mHz MAX 50 kHz Stored in volatile memory The FSK rate is ignored when the external source is selected FSK SOUR EXT FSKey INTernal RATE MINimum MAXimum Query the FSK rate Returns a value in hertz 168 Chapter 4 Remote Interface Reference Frequency Shift Keying FSK Commands FSKey SOURce INTernal EXTernal Select an internal or external FSK source The default is INT Stored in volatile memory e When the internal source is selected the rate at which the output frequency shifts between the carrier frequency and hop frequency is determined by the FSK rate specified FSK INT RATE e When the external source is selected the output frequency is determined by the signal level on the rear panel FSK terminal When a low TTL level is present the carrier frequency is output When a high TTL level is present the hop frequency is output
4. APPLy DC lt frequency DEFault gt lt amplitude DEFault gt lt offset gt 1 APPLy USER lt frequency gt lt amplitude gt lt offset gt 1 APPLy 223 Chapter 4 Remote Interface Reference SCPI Conformance Information Non SCPI Commands continued SOURce BM INTernal RAT BM INTernal RAT BM NCYCles BM SOURce BM SOURCe E E frequency MINimum MAXimum MINimum MAXimum lt cycles INFinity MINimum MAXimum BM NCYCles MINimum MAXimum BM PHASe lt degrees gt MINimum MAXimum BM PHASe MINimum MAXimum INTernal EXTernal BM STATe OFF ON BM STATe FM INTernal FUNCtion SINusoid SQUare TRIangle RAMP NOISe USER FM INTernal FUNCtion FSKey FREQuency frequency MINimum MAXimum FSKey FREQuency FSKey INTernal RAT MINimum MAXimum E rate in Hz gt MINimum MAXimum FSKey INTernal RATE MINimum MAXimum FSKey SOURce INTernal FSKey SOURce FSKey STATe OFF ON FSKey STATe FUNCtion USER arb name FUNCtion USER SWEep STAT SWEep STAT SYSTem LOCal REMote RWLock re OFF ON re EXTernal gt VOLATILI zai w 224 Chapter 4 Remote Interface Reference IEEE 488 Conformance Information IEEE 488 Conformance Information Dedica
5. This terminal is used in the following modes e Triggered Sweep Mode Press Single or execute TRIG SOUR EXT from the remote interface to enable the triggered sweep mode sweeps must be enabled When the rising edge of a TTL pulse is received on the Ext Trig terminal the function generator outputs a single sweep The Trig annunciator turns on when the function generator is waiting for a trigger e Externally Modulated FSK Mode To enable the externally modulated mode select FSK SRC EXT from the front panel MOD MENU or execute FSK SOUR EXT from the remote interface when FSK is enabled When a ow TTL level is present the FSK carrier frequency is output When a high TTL level is present the FSK hop frequency is output The Ext annunciator turns on when selected e Triggered Burst Mode Press Single or execute TRIG SOUR EXT from the remote interface to enable the triggered burst mode burst must be enabled When the rising edge of a TTL pulse is received the function generator outputs a burst waveform with the specified number of cycles The Trig annunciator turns on when the function generator is waiting for a trigger e External Gated Burst Mode To enable the external gated mode select BURST SRC EXT GATED from the front panel MOD MENU or execute BM SOUR EXT from the remote interface when burst is enabled When a high TTL level is present the function generator outputs the carrier wavefor
6. Output termination is 50 ohms Carrier waveshape is sine function output frequency is 5 kHz 5 Vpp Modulating waveshape is sine wave Modulating frequency is 500 Hz Frequency deviation is 250 Hz Turn FM modulation on Send 1 to output buffer when complete Enter value Disable interrupts SUB Err msg Error subprogram is called if errors occurred DIM Message 80 INTEGER Code COM Fgen B SPOLL Fgen Loop until error queue is cleared REPEAT OUTPUT Fgen SYST ERR ENTER Fgen Code Message PRINT Code Message UNTIL Code 0 STOP SUBEND Dimension array for error Define integer variable Use same address as in main program Use Serial Poll to read Status Byte all bits are cleared too 262 Chapter 6 Application Programs Using the Status Registers C GPIB Program 4 BRR RK KR RRR KR KK KKK kkk kkk kkk kkk kkk kkk kkk k k kkk k k k kkk kk kkk kk k k k k k k This program uses the Agilent 33120A Status Registers to generate an interrupt if a SCPI error is detected The function generator is programmed to output an FM waveform RR KK Re RR KK RR RK KR RRR KK KK ko ke KK include lt stdio h gt Used for printf include lt stdlib h gt Used for atoi include lt string h gt Used for strlen include lt cfunc h gt Header file from GPIB Command Library define ISC 7L Assign GPIB select code define ADDR 710L S
7. WAI Wait for all pending operations to complete before executing any additional commands over the interface Used only in the triggered burst mode and triggered sweep mode 210 Chapter 4 Remote Interface Reference An Introduction to the SCPI Language An Introduction to the SCPI Language SCPI Standard Commands for Programmable Instruments is an ASCII based instrument command language designed for test and measurement instruments Refer to Simplified Programming Overview starting on page 136 for an introduction to the basic techniques used to program the function generator over the remote interface SCPI commands are based on a hierarchical structure also known as a tree system In this system associated commands are grouped together under a common node or root thus forming subsystems A portion of the SOURCE subsystem is shown below to illustrate the tree system SOURce FREQuency STARt lt frequency gt MINimum MAXimum EQuency STARt MINimum MAXimum EQuency STOP frequency MINimum MAXimum EQuency STOP MINimum MAXimum nj Jj nj 3j nj Jj SWEep SPACing LINear LOGarithmic SWEep SPACing SWEep TIME lt seconds gt MINimum MAXimum SWEep TIME MINimum MAXimum SWEep STATe OFF ON SWEep STATe SOURce is the root keyword of the command FREQuency and SWEep are second level keywords and STARt and STOP are third level keywords A c
8. error is generated and the duty cycle is adjusted 139 Chapter 4 Remote Interface Reference Using the APPLy Command Output Amplitude e For the amplitude parameter of the APPLy command the output amplitude range depends on the function currently selected and the output termination You can substitute MINimum MAXimum or DEFault in place of a specific value for the amplitude parameter MIN selects the smallest amplitude for the selected function 50 mVpp into 50 ohms MAX selects the largest amplitude 10 Vpp into 50 ohms The default amplitude is 100 mVpp into 50 ohms for all functions Function Sine Square Triangle Ramp Noise Built In Arbs 1 Sine Square Triangle Ramp Noise Built In Arbs 1 Output Termination 50Q 50Q 50Q 50Q 50Q 50Q Open Circuit Open Circuit Open Circuit Open Circuit Open Circuit Open Circuit Minimum Amplitude 50 mVpp 50 mVpp 50 mVpp 50 mVpp 50 mVpp 50 mVpp 100 mVpp 100 mVpp 100 mVpp 100 mVpp 100 mVpp 100 mVpp Maximum Amplitude 10 Vpp 10 Vpp 10 Vpp 10 Vpp 10 Vpp 10 Vpp 20 Vpp 20 Vpp 20 Vpp 20 Vpp 20 Vpp 20 Vpp 1 There are five built in arbitrary waveforms stored in non volatile memory sinc negative ramp exponential rise exponential fall and cardiac e For arbitrary waveforms the maximum amplitude will be limited if the data points do not span the full range of the output DAC Digital to Analog
9. Chapter 8 Specifications Agilent 33120A Function Generator MODULATION CHARACTERISTICS AM Modulation Carrier 3 dB Freq Modulation Frequency Depth Source FM Modulation Modulation Frequency Peak Deviation Source Burst Modulation Carrier Frequency Count Start Phase Internal Rate Gate Source Trigger Source FSK Modulation Frequency Range Internal Rate 10 MHz typical Any internal waveform plus Arb 10 mHz to 20 kHz 0 05 to 2 5 kHz then decreases linearly to 0 4 at upper limit 0 to 120 Internal External Any internal waveform plus Arb 10 mHz to 10 kHz 0 05 to 600 Hz then decreases linearly to 0 8 at upper limit 10 mHz to 15 MHz Internal Only 5 MHz max 1 to 50 000 cycles or Infinite 360 to 360 10 mHz to 50 kHz 1 Internal or External Gate Single External or Internal Rate 10 mHz to 15 MHz 0 05 to 600 Hz then decreases linearly to 4 at upper limit 10 mHz to 50 kHz Source Internal External 1 MHz max FREQUENCY SWEEP Type Linear or Logarithmic Direction Up or Down Start F Stop F 10 mHz to 15 MHz Time 1ms to 500 sec 0 1 Source Single External or Internal REAR PANEL INPUTS External AM Modulation External Trigger FSK Burst Gate Latency Jitter 5 Vpk 100 Modulation 5 kQ Input Resistance TTL low true 1 3 us 25 ns SYSTEM CHARACTERISTICS Configuration Times 2 Function Change 80
10. PARAMETER choices The first parameter choice is CLEAR MEM for the NEW ARB command If you have previously downloaded any user defined waveforms you will also see commands like GET ARB on this level to load the specified waveform into volatile memory CLEAR MEM Enter 5 Turn on the waveform edit mode The function generator beeps and displays a message to show that the waveform edit mode is now enabled You are then exited from the menu Shift 6 Use Recall Menu to return to the NEW ARB command lt Recall Menu 1 NEW ARI i gt 7 Move across to the POINTS command on this level 2 POINTS v 8 Move down a level and set the number of points to 400 00400 PNTS n 04 Chapter 3 Features and Functions Arbitrary Waveforms Enter 9 Save the change and turn off the menu The function generator beeps and displays a message to show that the change is now in effect You are then exited from the menu COMPUTING Shift 10 Use Recall Menu to return to the POINTS command lt Recall Menu 2 POINTS For this example the pulse waveform will be high for one half of the cycle for 200 of the 400 points From the front panel each waveform point is a floating point value between 1 and 1 which correspond to the peak values of the waveform To define the waveform points use the LINE EDIT command in the EDIT MENU The function genera
11. Safety Notices Do not install substitute parts or perform any unauthorized modifica tion to the product Return the product to an Agilent Technologies Sales and Service Office for service and repair to ensure that safety features are maintained WARNING A WARNING notice denotes a hazard It calls attention to an operating proce dure practice or the like that if not correctly performed or adhered to could result in personal injury or death Do not proceed beyond a WARNING notice until the indicated conditions are fully understood and met CAUTION A CAUTION notice denotes a hazard It calls attention to an operating proce dure practice or the like that if not correctly performed or adhered to could result in damage to the product or loss of important data Do not proceed beyond a CAUTION notice until the indicated conditions are fully understood and met all Earth ground symbol gi Chassis ground symbol WARNING Only qualified service trained person nel who are aware of the hazards involved should remove the cover from the instrument WARNING For continued protection against fire replace the line fuse only with a fuse of the specified type and rating
12. Start and Stop frequencies 10 mHz to 15 MHz 100 kHz for triangle and ramp The sweep is phase continuous over the full frequency range The default start frequency is 100 Hz The default stop frequency is 1 kHz The RST command sets the start frequency to 10 mHz minimum and the stop frequency to 15 MHz maximum For arbitrary waveforms the maximum start or stop frequency depends on the number of points specified in the waveform The five built in arbitrary waveforms can be output at a maximum of 5 MHz Number of Arb Points Minimum Frequency Maximum Frequency 8 to 8 192 8k 10 mHz 5 MHz 8 193 to 12 287 12k 10 mHz 2 5 MHz 12 288 to 16 000 10 mHz 200 kHz To sweep up in frequency set the start frequency lt stop frequency To sweep down in frequency set the start frequency gt stop frequency The sync signal is a TTL low at the start of the sweep when the start frequency is output and is a TTL high at the end of the sweep when the stop frequency is output The signal is output from the front panel SYNC terminal Front Panel Operation After enabling sweeps press Recall Menu to go directly to the START F command in the menu 1 START F SWP MENU 2 STOP F SWP MENU Remote Interface Operation FREQuency STARt frequency MINimum MAXimum FREQuency STOP frequency MINimum MAXimum 95 Chapter 3 Features and Functions Frequency Sweep Sweep Time The
13. When the recall mode is enabled the function generator powers up in the power down configuration e The power down recall setting is stored in non volatile memory and does not change when power has been off or after a remote interface reset e The power down recall mode remembers the function including arbitrary waveforms frequency amplitude dc offset duty cycle as well as any modulation parameters e Any arbitrary waveforms downloaded to VOLATILE memory are not remembered However if an arbitrary waveform is being output from non volatile memory when the state is stored the waveform data is stored The stored waveform is output when the instrument state is recalled e Front Panel Operation 2 POWER ON SYS MENU To enable the recall mode select the LAST STATE choice To disable the recall mode select the DEFAULT choice 109 Chapter 3 Features and Functions System Related Operations Error Conditions When the front panel ERROR annunciator turns on one or more command syntax or hardware errors have been detected A record of up to 20 errors can be stored in the function generator s error queue See chapter 5 Error Messages for a complete listing of the errors e Errors are retrieved in first in first out FIFO order The first error returned is the first error that was stored When you have read all errors from the queue the ERROR annunciator turns off The function generator beep
14. C C UT QGFgen T oO O30 9 069 C J t o g g Ug Trigger the func trigger 710 RST UTP LOAD 50 PPL SIN 5000 5 UT Fgen BM NCYC 1 Fgen BM PHAS 270 UT Fgen VOLT OFFS 2 5 l RIG SOUR BUS UTPUT Fgen BM STAT ON tion generator over OUTPUT Fgen TRG Clear interface send device clear Assign I O path to address 710 Reset Outpu the function generator t termination is 50 ohms Carrier is 5 kHz sine 5 Vpp Burst count is 1 cycle Starting phase is 270 degrees Offse the G or T t voltage is 2 5 Vdc Trigger source is bus Turn burst modulation on PIB interface RIGGER 710 248 Chapter 6 Application Programs Using the APPLy Command C GPIB Program 1 BR KK KK RRR KKK RR KK KK KK KR KK RR RK KK RK kkk k kkk kkk k k kkk k k kk k k k This program sets up a burst waveform with a 270 degree starting phase By adding an offset voltage to the burst a haversine is created This program also shows the use of a trigger received over the GPIB interface to initiate a single burst RR RK RR KKK RRR KR RRR KK KK ko ke kK J include lt stdio h gt Used for printf include lt stdlib h gt Used for atoi include lt string h gt Used for strlen include lt cfunc h gt Header file from GPIB Command Library define ADDR 710L Set GPIB address for function g
15. ENTER NUM flashes on the display indicating that the number mode is enabled 50 To cancel the number mode press Shift Cancel Set the units to the desired value The units are selected using the arrow keys on the right side of the front panel As soon as you select the units the function generator outputs the waveform with the displayed amplitude To turn off the flashing digit move the cursor to the left of the display using the arrow keys 50 00 mVRMS You can also use the knob and arrow keys to enter a number See Front Panel Number Entry on page 3 for more information 20 Offset Enter Number t 1 5j Shift v kHz m Vrms n 2 an Chapter 1 Quick Start To set a dc offset voltage To set a dc offset voltage At power on the function generator outputs a sine wave with a dc offset voltage of 0 volts into a 50Q termination The following steps show you how to change the offset to 1 5 mVdc Enable the offset modify mode The displayed offset voltage is either the power on value or the previous offset selected When you change functions the same offset is used if the present value is valid for the new function 0 000 VDC Enter the magnitude of the desired offset 9 Notice that the Num annunciator turns on and ENTER NUM flashes on the display indicating that the number mode is enabled Notice that toggles the
16. Shift Store again or let the display time out after 10 seconds Save the instrument state The instrument state is now stored To recall the stored state turn to the next page You can also use the knob or enter number mode to enter a memory location See Front Panel Number Entry on page 3 for more information 25 Chapter 1 Quick Start To store the instrument state To verify that the state was stored properly you can turn the power off before recalling the state Recall 5 Recall the stored instrument state To recall the stored state you must use the same memory location used previously to store the state Use the up and down arrow keys to change the displayed storage location D To cancel the restore operation press Recall again This message appears on the display for approximately 10 seconds Repeat this step as needed Enter 6 Restore the instrument state The function generator should now be configured in the same state as when you stored the setup on the previous page When power is turned off the function generator automatically stores its state in memory location 0 You can recall the power down state but you cannot store the state to location 0 from the front panel Use the POWER ON LAST STATE command in the SYS MENU to automatically recall the power down state when power is turned on See chapter 2 for more information on using the
17. User s Guide Publication Number 33120 90006 order as 33120 90104 manual set Edition 6 March 2002 Copyright Agilent Technologies Inc 1994 2002 For Safety information Warranties and Regulatory information see the pages following the Index Agilent 33120A 15 MHz Function Arbitrary Waveform Generator Note Unless otherwise indicated this manual applies to all Serial Numbers The Agilent Technologies 33120A is a high performance 15 MHz synthesized function generator with built in arbitrary waveform capability Its combination of bench top and system features makes this function generator a versatile solution for your testing requirements now and in the future Convenient bench top features 10 standard waveforms Built in 12 bit 40 MSa s arbitrary waveform capability Easy to use knob input Highly visible vacuum fluorescent display Instrument state storage Portable ruggedized case with non skid feet Flexible system features Four downloadable 16 000 point arbitrary waveform memories GPIB IEEE 488 interface and RS 232 interface are standard SCPI Standard Commands for Programmable Instruments compatibility Agilent IntuiLink Arb Waveform Generation Software for Microsoft Windows included Agilent 33120A 15 MHz Function Arbitrary Waveform Generator The Front Panel at a Glance D MENU On Off m FUNCTION MODULATION AM FM FSK Burst Sweep Enter Arb List
18. 90 180 270 360 I lt One Cycle of Memory 279 48 Bit PIR Chapter 7 Tutorial Output Amplitude Control Output Amplitude Control The 33120A uses a 12 bit digital to analog converter DAC to convert the digital representation of a signal to an analog output voltage The DAC can create waveforms represented by 4 096 21 discrete amplitude levels All 4 096 amplitude codes are used for the built in waveforms Output levels from full maximum to minimum output are controlled by applying varying amounts of signal gain or attenuation to the signal created by the DAC as shown in the block diagram below The output waveform is always described by the full 12 bit vertical resolution You can download user defined arbitrary waveforms using less than the full 12 bit vertical resolution however it is recommended that you always use the full DAC amplitude resolution to minimize amplitude quantization errors as previously discussed Ss Ge Clock Ner Anti Alias Ter Filter 500 48 Bit Wim E eds REN FoU ES PIR gt RAM gt DAC P Sin eon VVV oO lt 14 Bit 12 Bit c lt 5 Address Data Amplitude Data NA N wy Step Attenuator Load 280 Chapter 7 Tutorial Output Amplitude Control As shown below the 33120A has a fixed output source resistance of 50 ohms During calibration output amplitudes are calibrated for both the open circuit voltage
19. DEL command to delete the waveform in VOLATILE memory or any of the user defined waveforms in non volatile memory 184 Chapter 4 Remote Interface Reference Arbitrary Waveform Commands DATA NVOLatile FREE Query the number of non volatile memory slots available to store user defined waveforms Non volatile waveform memory is divided into four 16k point slots This command returns the number of memory slots available to store user defined waveforms 0 memory is full 1 2 9 or 4 FORMat BORDer NORMal SWAPped Used only for binary block transfers Select the byte order for binary transfers in the block mode using the DATA DAC command The default is NORM e In NORM byte order default the most significant byte MSB of each data point is sent first e In SWAP byte order the least significant byte LSB of each data point is sent first Most PCs use the swapped byte order e The function generator represents binary data as 12 bit integers which are sent as two bytes Each data point in the waveform requires 12 bits which must be transferred as 16 bits two bytes on the function generator s 8 bit interface FORMat BORDer Query the byte order configuration Returns NORM or SWAP 185 First time SCPI users see page 211 Chapter 4 Remote Interface Reference Triggering Triggering See also Triggering starting on page 98 in chapter 3 A
20. STB command does not clear the Status Byte summary register Using the Message Available Bit MAV You can use the Status Byte message available bit bit 4 to determine when data is available to read into your bus controller The function generator subsequently clears bit 4 only after all messages have been read from the output buffer To Interrupt Your Bus Controller Using SRQ 1 Send a device clear message to clear the function generator s output buffer e g CLEAR 710 2 Clear the event registers with the CLS clear status command 3 Set up the enable register masks Execute the ESE command to set up the Standard Event register and the SRE command for the Status Byte 4 Send the OPC operation complete query command and enter the result to ensure synchronization 5 Enable your bus controller s IEEE 488 SRQ interrupt 205 Chapter 4 Remote Interface Reference The SCPI Status Registers To Determine When a Command Sequence is Completed Send a device clear message to clear the function generator s output buffer e g CLEAR 710 Clear the event registers with the CLS clear status command Enable the operation complete bit bit 0 in the Standard Event register by executing the ESE 1 command Send the OPC operation complete query command and enter the result to ensure synchronization Execute your command string to program the desired configuration a
21. directly to the AM SHAPE command in the menu 1 AM SHAPE MOD MENU Remote Interface Operation AM INTernal FUNCtion SINusoid SQUare TRIangle RAMP NOISe USER 73 Chapter 3 Features and Functions Amplitude Modulation AM Modulating Waveform Frequency The function generator will accept an internal modulating signal an external modulating signal or both Modulating frequency internal source 10 mHz to 20 kHz The default is 100 Hz The sync signal for AM is referenced to the modulating signal not the carrier A momentary TTL high pulse gt 200 ns is output at each zero crossing point of the modulating signal The signal is output from the front panel SYNC terminal Front Panel Operation Press Shift Freq to set the modulating frequency the value is displayed for approximately 10 seconds Before setting the modulating frequency from the front panel you must have AM enabled If you attempt to set the frequency when AM is not enabled SELECT AM FM is displayed Remote Interface Operation AM INTernal FREQuency lt frequency gt MINimum MAXimum Modulation Depth The modulation depth is expressed as a percentage and represents the extent of the amplitude variation At 0 modulation the output amplitude is half of the selected value At 100 modulation the output amplitude equals the selected value Modulation depth 0 to 120 The default is 100 Fro
22. limits 59 148 modulation 71 154 remote interface selection 148 restrictions with offset 60 149 selecting units 64 150 angle bursts 89 163 annunciators front panel 5 application programs 243 269 APPLy command 136 138 144 MIN MAX parameters 143 optional parameters 143 Arb annunciator 5 arbitrary waveforms amplitude limitations 148 177 average value 181 binary data 179 built in waveforms 175 catalog listing 182 184 copy name 182 crest factor value 181 delete waveform 183 download speeds 299 example program GPIB 255 example program RS 232 267 floating point data 178 frequency limits 57 146 front panel operation 103 108 inherent offset 63 177 memory available 185 memory limitations 183 modulation matrix 56 177 naming rules 176 182 number of points 181 parity and data bits 116 195 peak to peak value 181 remote operation 174 185 reserved names 182 tutorial overview 278 average value of waveform 181 285 B BASIC examples 244 baud rate RS 232 choices 116 195 factory setting 116 195 selecting 219 beep 189 binary data arb waveforms 179 block format 180 byte order 185 bit definitions standard event register 207 status byte 203 block format binary data 180 blue Shift key 14 BM INT RATE command 164 BM NCYC command 162 BM PHAS command 163 BM SOUR command 164 BM STAT command 165 Borland Turbo C 244 braces syntax 127 bracke
23. steps from the start frequency to the stop frequency at a sweep rate which you specify You can sweep up or down in frequency and with either linear or logarithmic spacing You can also configure the function generator to output a single sweep one pass from start frequency to stop frequency by applying an external trigger The function generator can produce a frequency sweep for sine square triangle ramp or arbitrary waveforms For more information on the fundamentals of frequency sweeps refer to chapter 7 Tutorial To Select Sweep Modulation e The Swp annunciator turns on when the sweep mode is enabled e Only one modulation mode can be enabled at a time When you enable the sweep mode the previous modulation mode is turned off e Front Panel Operation Enable the sweep mode before you set up the other sweep parameters Press Shift Sweep to output a sweep using the present settings for amplitude and offset voltage e Remote Interface Operation To ensure proper operation you should enable the sweep mode after you have set up the other modulation parameters SWEep STATe OFF ON 94 Chapter 3 Features and Functions Frequency Sweep Start Frequency and Stop Frequency The start frequency and stop frequency set the upper and lower frequency bounds for the sweep The function generator begins at the start frequency sweeps to the stop frequency and then resets back to the start frequency
24. the maximum frequency depends on the number of points specified in the waveform As shown below the maximum output frequency decreases as you specify more points in the waveform The five built in arbitrary waveforms can be output at a maximum of 5 MHz Number of Arb Points Minimum Frequency Maximum Frequency 8 to 8 192 8k 100 Hz 5 MHz 8 193 to 12 287 12k 100 Hz 2 5 MHz 12 288 to 16 000 100 Hz 200 kHz e Possible Conflict with Function Change The output frequency is automatically adjusted if you select a function whose maximum frequency is less than that of the currently active function For example if you output a 1 MHz sine wave and then change the function to triangle wave the function generator will adjust the output to 100 kHz the upper limit for triangle waves From the remote interface a 221 Settings conflict error is generated and the frequency is adjusted e Possible Conflict with Duty Cycle square wave only For output frequencies above 5 MHz the duty cycle is limited to values between 40 and 60 below 5 MHz the range is 20 to 80 The duty cycle is automatically adjusted if you select a frequency that is not valid with the present duty cycle For example if you set the duty cycle to 70 and then change the frequency to 8 MHz the function generator will automatically adjust the duty cycle to 60 the upper limit for this frequency From the remote interface a 221 Settings conflict
25. waveforms For this example select a sine wave with a 5 Vpp amplitude Enable the sweep mode Notice that the Swp annunciator turns on Use the menu to select the start frequency After you enable the sweep mode the recall menu key will automatically take you to the START F command in the SWP MENU 49 Enter Shift lt Recall Menu Enter Chapter 2 Front Panel Menu Operation To output a frequency sweep Move down a level and set the start frequency to 50 Hz Notice that the Swp annunciator flashes indicating that the displayed parameter is for the sweep mode For more information on editing numbers in the menu refer to Menu Example 3 earlier in this chapter A50 00 Hz Save the change and turn off the menu The start frequency is now set to 50 Hz Use recall menu to return to the START F command The recall menu key returns you to the START F command which was the last command used before you exited the menu 1 START F Move across to the STOP F command 2 STOP F Move down a level and set the stop frequency to 5 kHz A5 000 KHz Save the change and turn off the menu At this point the function generator outputs a continuous sweep from 50 Hz to 5 kHz You can generate one frequency sweep by pressing the Single key or applying a trigger pulse to the rear panel Ext Trig terminal For more information see To trigger a burst or sweep on the next
26. 259 Chapter 6 Application Programs Downloading an Arbitrary Waveform over GPIB continued void check_error char func_name Read error queue to determine if errors have occurred char message 80 int length 80 IOOUTPUTS ADDR SYST ERR 9 Read the error queue IOENTERS ADDR message amp length Enter error string while atoi message 0 Loop until all errors are read printf Error s in function s n n message func_name IOOUTPUTS ADDR SYST ERR 9 IOENTERS ADDR message amp length BK RRR KK KR KKK KR KK RK KKK RK RRR ckokckckck ck KKK KKK KKK KK End of Program 3 260 Chapter 6 Application Programs Using the Status Registers Using the Status Registers This program teaches the following concepts e How to use the Status Registers to generate an interrupt if a SCPI error occurs The program sets up the Status Byte and Standard Event register and interrupts the controller if an error is detected e How to service the interrupt if an error occurs and read the function generator s error queue using the SYST ERR command BASIC GPIB Program 4 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 This program uses the status registers to generate an interrupt if a SCPI error occurs The function generator is programmed to output an FM w
27. 284 Ctrl C character 199 cycles burst 87 162 D damped sine wave example 267 data bits RS 232 arb waveform limits 116 195 choices 116 195 factory setting 116 195 selecting 220 data frame RS 232 196 data points arb waveforms 181 DATA VOLATILE command 178 DATA ATTR AVER command 181 DATA ATTR CFAC command 181 DATA ATTR POIN command 181 DATA ATTR PTP command 181 DATA CAT command 182 DATA COPY command 182 DATA DAC VOLATILE command 179 DATA DEL command 183 DATA DEL ALL command 184 DATA NVOL CAT command 184 DATA NVOL FREE command 185 dBm 64 150 286 dc offset and arb waveforms 63 177 and dc voltage function 62 150 and output termination 62 150 front panel selection 21 remote interface selection 149 dc volts front panel selection 24 selecting 62 150 with APPLy 144 declaration of conformity 309 deviation peak frequency 80 158 device clear 216 digits maximum number 112 dimensions product 301 direct digital synthesis 273 DISP command 188 DISP TEXT command 188 DISP TEXT CLE command 189 display annunciators 5 enable disable 112 188 text message 112 188 d Hi download speeds arb waveforms GPIB 299 arb waveforms RS 232 299 downloading arb data binary data 179 floating point data 178 DSR line RS 232 197 198 DTR line RS 232 197 198 duty cycle conflict with frequ
28. 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 310 320 330 340 This program teaches the following concepts e How to define a set of binary waveform points and download the points to volatile memory The downloaded waveform is a damped e How to copy the download waveform to non volatile memory This program shows how to download an arbitrary waveform using binary data over the RS 232 interface The program generates a damped sine wave using 16 000 points PTION BASE 1 TROL 10 3 9600 TROL 10 4 7 EGER Waveform 16000 1I Ncycles 1 Damp factor IGN Fgen TO 10 SSIGN Bin TO 10 FORMAT OFF UTPUT Fgen RST z HQQO o 4 ZO x D Qpp wy n Nn UTPUT Fgen SYST REM UTPUT Fgen FORM BORD SWAP UTPUT Fgen FREQ 5000 UTPUT Fgen OUTP LOAD 50 UTPUT Fgen VOLT 5 ooooo Ncycles 10 Damp factor 5 Calculate data points DISP Calculating Data Points FOR I 1 TO 16000 IF I 14000 THEN ELSE Waveform I z0 END IF NEXT I Configure PC for 9600 baud COM2 Configure PC for 8 bits with no parity Dimension array and variables Define real variable Device address is 10 Prepare interface for binary data Reset the function generator Enable the remote RS 232 mode Swap data bytes send LSB first Output frequency is 5 kHz Output termination is 50 ohms Ou
29. ADDR P ud 48 Bit om e Time Clock Cycles 275 Chapter 7 Tutorial Signal Imperfections The maximum output frequency with the condition that every waveshape point in RAM is output every waveform cycle is defined by Fout Felk Points The minimum number of points required to accurately reproduce a waveshape will determine the maximum useful output frequency using the same equation The rule governing waveforms is referred to as the Nyquist Sampling Theorem which states that you must include at least two points from the highest frequency component of the signal you are attempting to reproduce Signal Imperfections Most signal imperfections are easiest to observe in the frequency domain using a spectrum analyzer Sampling theory predicts the location and size of spurious signals resulting from the sampling processes used by DDS generators In fact since DDS generators use a fixed sampling rate 40 MHz for the 33120A spurious signals can be removed with a fixed frequency anti alias filter A 17 MHz ninth order elliptical filter providing a sharp cut off in excess of 60 dB attenuation for signals greater than 19 MHz is used for sine wave outputs A 10 MHz seventh order Bessel filter is used for non sine wave outputs The Bessel filter provides slower amplitude roll off for anti alias filtering but maintains linear phase response to minimize shape distortion for complex waveshapes The 33120A au
30. BURST CNT 5 BURST RATE 9 c 6 BURST PHAS gt 7 BURST SRC 7 8 FSK FREQ gt 9 FSK RATE 10 FSK SRC Ocoo uoon05towzi B SWP Sweep MENU AM SHAPE AM SOURCE FM SHAPE BURST CNT BURST RATE BURST PHAS BURST SRC FSK FREQ FSK RATE FSK SRC Selects the shape of the AM modulating waveform Enables or disables the internal AM modulating source Selects the shape of the FM modulating waveform Sets the number of cycles per burst 1 to 50 000 cycles Sets the burst rate in Hz for an internal burst source Sets the starting phase angle of a burst 360 to 360 degrees Selects an internal or external gate source for burst modulation Sets the FSK hop frequency Selects the internal FSK rate between the carrier and FSK frequency Selects an internal or external source for the FSK rate 1 START F 2 STOP F amp 3 SWP TIME gt 4 SWP MODE kOND C EDIT MENU START F STOP F SWP TIME SWP MODE Sets the start frequency in Hz for sweeping Sets the stop frequency in Hz for sweeping Sets the repetition rate in seconds for sweeping Selects linear or logarithmic sweeping 1 NEW ARB 2 POINTS gt 3 LINE EDIT gt 4 POINT EDIT gt 5 INVERT gt 6 SAVEAS 7 DELETE NOM O D TA NEW ARB POINTS LINE EDIT POINT EDIT INVERT SAVE AS DELETE Initiates a new arb waveform or loads the selected arb waveform Set
31. E fe RE Arb Recall Menu 33120A 16 MHz Function Arbitrary Wavdform Generator YE Agilent 24 FUNCTION MODULATION MENU uid AM FM FSK Burst Sweep Arb List On Off mVpp Power v g Iv p lies js Enter J m Vrms N MNM OUTPUT Freq Level Duty Internal Store Cancel Hz a Off Freq Anot greet Single Recall Enter E dBm O 6 1 8 9 0 p Nubar KJ Back Space t MODIFY 2 TRG STATE LOCAL Nosal Mani J L J L J L L J L i L J L J L J L I L es eo eo ee ee Js eps oos Je s n peii f AM FM Freq Level Duty z MHz Fees nen Brive mMpp IP m Vrms T MODIFY C a dBm E Back Space Function Modulation keys Menu operation keys Waveform modify keys Single Internal Trigger key Burst and Sweep only RON ONO Recall Store instrument state key Enter Number key Shift Local key Enter Number units keys Front Panel Number Entry You can enter numbers from the front panel using one of three methods Use the knob and the arrow keys to modify the displayed number Use the arrow keys to edit individual digits A Increments the flashing digit v Decrements the flashing digit gt Moves the flashing digit to the right lt Moves the flashing digit to the left Use the Enter Num
32. Fgen OUTP LOAD 50 Output termination is 50 ohms UT Fgen FUNC SHAP SIN Carrier waveshape is sine wave UT Fgen FREQ 5000 VOLT 5 Carrier frequency is 5 kHz 5 Vpp i i GFgen AM INT FUNC SIN Modulating waveshape is sine i i i C C UT QGFgen AM INT FREQ 200 Modulating frequency is 200 Hz UT QFgen AM DEPT 80 Modulation depth is 80 UTPUT Fgen AM STAT ON Turn AM modulation on C ooooooco J UCU CU UU Ug C OUTPUT Fgen SAV 1 Store state in memory location 1 Use the RCL 1 command to recall the stored state 252 Chapter 6 Application Programs Using the Low Level Commands QuickBASIC GPIB Program 2 REM SINCLUDE QBSETUP This program uses low level SCPI commands to configure the function generator to output an AM waveform This program also shows how to use state storage to store the instrument configuration in memory The program is written in QuickBASIC and uses the 82335B GPIB card and GPIB command library ISC amp 7 GPIB select code is 7 Dev amp 710 Assign I O path to address 710 Timeout 5 Configure device library for a 5 second timeout CALL IOTIMEOUT ISC amp Timeout IF PCIB ERR NOERR THEN ERROR PCIB BASERR CALL IORESET ISC amp Reset the 82335B GPIB card IF PCIB ERR NOERR THEN ERROR PCIB BASERR CALL IOCLEAR Dev amp Send a device clear to
33. For dc volts the output level is actually controlled by setting the offset voltage You can set the dc voltage to any value between 5 Vdc into 50 ohms or 10 Vdc into an open circuit To select de volts from the front panel press Otfset and hold it down for more than 2 seconds 62 Chapter 3 Features and Functions Output Configuration e For arbitrary waveforms the Offset annunciator will turn on if the waveform data has an inherent offset present if the average is not equal to zero The function generator calculates the average of the data points and compares the average to zero volts If the average is not within two DAC Digital to Analog Converter counts of zero volts the Offset annunciator turns on e Front Panel Operation To set the dc offset press Offset Then use the knob arrow keys or Enter Number mode to set the offset e Remote Interface Operation VOLTage OFFSet lt offset gt MINimum MAXimum You can also use the APPLy command to select the function frequency amplitude and offset with a single command 63 Chapter 3 Features and Functions Output Configuration Output Units Applies only to output amplitude does not affect offset At power on the units for output amplitude are volts peak to peak Output units Vpp Vrms or dBm The default is Vpp The unit setting is stored in volatile memory the units are set to Vpp when power has been off or after a rem
34. No expansion or compression is performed on the modulation waveform data for certain modulation frequencies 293 Chapter 7 Tutorial Modulation You can use the equations on the next page to determine specific waveform lengths and modulation frequencies when more precise control is needed Normally you should not have to perform these calculations The function generator incorporates an internal 8 bit 7 bits peak digital to analog converter DAC to create an analog copy of the modulation signal for amplitude modulation AM This signal is internally applied to a conventional four quadrant analog multiplier circuit to achieve amplitude modulation Similarly the generator uses digital signal processing to combine the carrier and modulation signals for frequency modulation FM The FM modulation signal maintains 12 bit resolution for frequency values The following equations and example describe the capabilities and limitations of the 33120A s internal modulation signal generator Parameter Definitions Maximum Point Clock C 5 MSa s for AM 1 25 MSa s for FM Modulation Prescaler S integer numbers truncated from 1 2 3 22 Constant k 4 900 for AM 624 for FM Modulation Frequency F 10 mHz to 20 kHz for AM 10 mHz to 10 kHz for FM Points P values from 2 000 to 4 000 even numbers only rounded down 294 Chapter 7 Tutorial Modulation Equations Compute the modulat
35. Q 1 75 dBm 600 Q dBm 50 0 10 79 286 Chapter 7 Tutorial Modulation Modulation Modulation is the process of combining a high frequency carrier signal and a low frequency information signal How these signals are combined is determined by the specific type of modulation used The two most common types of modulation are amplitude modulation AM and frequency modulation FM The information signal that modulates or varies the carrier waveform can be of any form sine wave square wave arbitrary wave or random noise In general the carrier signal may also be of any shape but it is usually a sine wave of constant amplitude and frequency for most communications systems During modulation the simple carrier waveform is converted into a complex waveform by the lower frequency information signal Generally the higher frequency carrier waveform is used to efficiently transmit the complex modulated signal over long distances Amplitude Modulation AM Amplitude Modulation is a process of producing a waveform whose amplitude varies as a function of the instantaneous amplitude of the modulating information signal In other words the information signal creates an amplitude envelope around the carrier signal The 33120A implements double sideband transmitted carrier amplitude modulation similar to a typical AM radio station A constant is added to the AM modulating signal so that the sum is always greater than
36. TRIangle lt frequency gt lt amplitude gt lt offset gt APPLy RAMP lt frequency gt lt amplitude gt lt offset gt 1 APPLy NOISe lt frequency DEFault gt 1 amplitude lt offset gt 1 APPLy DC frequency DEFault 5 amplitude DEFault gt t offset 1 APPLy USER lt frequency gt lt amplitude gt lt offset gt 1 APPLy This parameter is ignored for this command but you MUST specify a value or DEFault 127 Chapter 4 Remote Interface Reference SCPI Command Summary Output Configuration Commands see page 145 for more information SOURce FUNCtion SHAPe SINusoid SQUare TRIangle RAMP NOISe DC US FUNCtion SHAPe Gl R SOURce FREQuency frequency MINimum MAXimum FREQuency MINimum MAXimum SOURce PULSe DCYCle lt percent gt MINimum MAXimum PULSe DCYCle MINimum MAXimum SOURce VOLTage lt amplitude gt MINimum MAXimum VOLTage MINimum MAXimum VOLTage OFFSet offset MINimum MAXimum VOLTage OFFSet MINimum MAXimum VOLTage UNIT VPP VRMS DBM DEFault VOLTage UNIT OUTPut LOAD 50 INFinity MINimum MAXimum OUTPut LOAD MINimum MAXimum OUTPut SYNC OFF ON OUTPut SYNC SAV 0 1 2 3 State 0 is the instrument state at power down RCL 0 1 2 3 States 1 2 and 3 are user defined instrument states MEMory STATe DELete 0 1 2 3 Default parameters are sho
37. a carrier waveform and a modulating waveform In AM the amplitude of the carrier is varied by the amplitude of the modulating waveform The function generator will accept an internal modulating signal an external modulating signal or both For more information on the fundamentals of Amplitude Modulation refer to chapter 7 Tutorial To Select AM Modulation e The AM annunciator turns on when AM is enabled e Only one modulation mode can be enabled at a time When you enable AM the previous modulation mode is turned off e Front Panel Operation Enable AM before setting up the other modulation parameters Press Shift AM to output an AM waveform using the present settings for the carrier frequency modulating frequency output amplitude and offset voltage e Remote Interface Operation To ensure proper operation you should enable AM after you have set up the other modulation parameters AM STATe OFF ON 71 Chapter 3 Features and Functions Amplitude Modulation AM Carrier Waveform Shape e AMcarrier shape Sine Square Triangle Ramp or Arbitrary waveform The default is Sine e You cannot use the noise function or dc volts as the carrier waveform e Front Panel Operation Press any of the front panel function keys except Noise For arbitrary waveforms the waveform that is currently downloaded e Remote Interface Operation FUNCtion SHAPe S Arb key sele
38. also trigger the function generator from the GPIB interface by sending the IEEE 488 Group Execute Trigger GET message e g TRIGGER 710 e When the External or Bus trigger source is selected the burst count and burst phase remain in effect but the burst rate is ignored 165 TRIGger SOURce continued Chapter 4 Remote Interface Reference Burst Modulation Commands When the External gate source is selected gated burst mode the specified trigger source is ignored The external gated mode overrides the triggered mode source To ensure synchronization when the Bus source is selected send the WAI wait command When the WAI command is executed the function generator waits for all pending operations to complete before executing any additional commands For example the following command string guarantees that the first trigger is accepted and executed before the second trigger is recognized TRIG SOUR BUS TRG WAI TRG WAI You can use the OPC operation complete query command or the OPC operation complete command to signal when the burst is complete The OPC command returns 1 to the output buffer when the burst is complete The OPC command sets the operation complete bit bit 0 in the Standard Event register when the burst is complete TRIGger SOURCe Query the present trigger source Returns IMM EXT or BUS 166 en Chapter 4 Remot
39. also use the APPLy command to select the function frequency amplitude and offset of the carrier with a single command 91 Chapter 3 Features and Functions Frequency Shift Keying FSK Modulation FSK Hop Frequency Hop frequency 10 mHz to 15 MHz 100 kHz for triangle and ramp The default is 100 Hz You can use sine square ramp triangle or arbitrary waveforms for the hop frequency waveshape For arbitrary waveforms the maximum hop frequency depends on the number of points specified in the waveform The five built in arbitrary waveforms can be output at a maximum of 5 MHz Number of Arb Points 8 to 8 192 8k 8 193 to 12 287 12k 12 288 to 16 000 Minimum Frequency 10 mHz 10 mHz 10 mHz Maximum Frequency 5 MHz 2 5 MHz 200 kHz For an externally controlled FSK waveform the carrier frequency is output when a low TTL level is applied to the FSK terminal The hop frequency is output when a high TTL level is applied For FSK the sync signal is referenced to the FSK hop signal not the carrier A momentary TTL high pulse gt 200 ns is output on the transition to the hop frequency The signal is output from the front panel SYNC terminal Front Panel Operation After enabling FSK press Recall Menu to go directly to the FSK FREQ command in the menu 8 FSK FREQ MOD MENU Remote Interface Operation FSKey FREQuency lt frequency gt MINimum
40. are reserved and cannot be used with the DATA COPY command SINC NEG_RAMP EXP_RISE EXP_FALL and CARDIAC Arb waveform name too long The arb name can contain up to 8 characters used with DATA COPY command The first character must be a letter A Z but the remaining characters can be numbers 0 9 or the underscore character _ Blank spaces are not allowed Name of source arb waveform for copy must be VOLATILE The DATA COPY command copies the arbitrary waveform downloaded into VOLATILE memory to the specified name The source for the copy operation is always VOLATILE you cannot copy from any other name 240 785 786 787 788 790 800 810 Chapter 5 Error Messages Arbitrary Waveform Errors Specified arb waveform does not exist The arb name specified with the FUNC USER or DATA DEL command has not been downloaded into memory Use the DATA CAT command to list all waveforms currently downloaded To download a waveform into memory use the DATA VOLATILE or DATA DAC VOLATILE commands This error may also be generated if you insert a space instead of a colon before the ALL parameter in the DATA DEL ALL command The colon before the ALL parameter is required otherwise the function generator will attempt to delete the arbitrary waveform with the name ALL Cannot delete a built in arb waveform You cannot delete any of the five built in arbit
41. calibration count increments up to a maximum of 32 767 after which it wraps around to 0 Since the value increments by one for each calibration point a complete calibration will increase the value by many counts Front Panel Operation 3 CAL COUNT CAL MENU Remote Interface Operation CALibration COUNt 121 Chapter 3 Features and Functions Calibration Overview Calibration Message You can use the calibration message feature to record calibration information about your function generator For example you can store such information as the last calibration date the next calibration due date the instrument serial number or even the name and phone number of the person to contact for a new calibration You can record information in the calibration message only from the remote interface However you can read the message from either the front panel menu or the remote interface e The calibration message may contain up to 40 characters However the function generator can display only 11 characters of the message on the front panel additional characters are truncated e The calibration message is stored in non volatile memory and does not change when power has been off or after a remote interface reset e Front Panel Operation 4 MESSAGE CAL MENU Read the cal message e Remote Interface Operation CALibration STRing lt quoted string gt Store the cal message The following command string shows how to store a ca
42. change the output termination For example if you set the amplitude to 10 Vpp and then change the termination from 50 ohms to high impedance the displayed amplitude will double to 20 Vpp If you change from high impedance to 50 ohms the displayed amplitude will drop in half See the OUTP LOAD command for more information VOLTage MINimum MAXimum Query the output amplitude for the currently selected function Returns the magnitude of the output amplitude Units are not returned but are in the units set by the most recent VOLT UNIT command VOLTage OFFSet lt o ffset gt MINimum MAXimum Set the dc offset voltage for the currently active function MIN selects the smallest dc offset voltage for the selected function 0 volts MAX selects the largest offset for the selected function The default offset voltage is 0 volts for all functions Stored in volatile memory e You can set the offset to a positive or negative number with the restrictions shown below If the specified offset voltage is not valid the function generator will automatically adjust it to the maximum dc voltage allowed with the present amplitude Vmax is the maximum peak to peak amplitude for the selected output termination Vpp is the output amplitude in volts peak to peak From the remote interface a 221 Settings conflict error is generated and the offset is adjusted V Voffset ar lt Vmax and Voffset lt 2x Vpp
43. choice on this level A MOD MENU Move across to the SYS MENU choice on this level There are six menu group choices available on the MENUS level Each choice has a letter prefix for easy identification A B etc D SYS MENU Move down to the COMMANDS level within the SYS MENU The OUT TERM command is your first choice on this level 1 OUT TERM Move across to the POWER ON command on this level There are six command choices available in the SYS MENU Each choice on this level has a number prefix for easy identification 1 2 etc 2 POWER ON You can also use the knob to scroll left or right through the choices on each level of the menu 35 Enter Chapter 2 Front Panel Menu Operation A front panel menu tutorial Move down a level to the PARAMETER choices The first parameter choice is DEFAULT for the POWER ON command DEFAULT is the factory setting and is stored in non volatile memory DEFAULT Move across to the LAST STATE choice 1 There are two parameter choices for POWER ON LAST STATE Save the change and turn off the menu The function generator beeps and displays a message to show that the change is now in effect You are then exited from the menu ENTERED Cycle the power to restore the default values Turn the function generator OFF and then ON The default output state will now be in effect 1 kHz sine wave 1
44. contains several remote interface application programs to help you develop programs for your own application Chapter 4 Remote Interface Reference starting on page 125 lists the syntax for the SCPI Standard Commands for Programmable Instruments commands available to program the function generator BASIC Language Programs All of the BASIC example programs in this chapter were developed and tested on an HP 9000 Series 300 controller Each device on the GPIB IEEE 488 interface must have a unique address You can set the function generator s address to any value between 0 and 30 The current address is displayed momentarily on the front panel when you turn on the function generator The GPIB IEEE 488 address is set to 10 when the function generator is shipped from the factory The example programs in this chapter assume an GPIB address of 10 When sending a command over the remote interface you append this address to the GPIB interface s select code normally 7 For example if the select code is 7 and the device address is 10 the combination is 710 C Language Programs All of the C Language example programs in this chapter are written for the 82335 GPIB Interface Card using the GPIB Command Library for C Unless otherwise noted the library functions used in the example programs are compatible with the ANSI C standard All of the C Language programs were compiled and tested using the f
45. counter to generate sequential RAM addresses an adder is used On each clock cycle the constant loaded into the phase increment register PIR is added to the present result in the phase accumulator see below The most significant bits of the phase accumulator output are used to address waveform RAM the upper 14 bits 214 16 384 RAM addresses for the 33120A By changing the PIR constant the number of clock cycles required to step through the entire waveform RAM changes thus changing the output frequency When a new PIR constant is loaded into the register the waveform output frequency changes phase continuously following the next clock cycle The 33120A uses a 48 bit phase accumulator which yields Felk 248 or approximately 142 nHz frequency resolution internally The phase accumulator output the upper 14 bits will step sequentially through each RAM address for smaller PIR values lower frequencies However when the PIR is loaded with a larger value the phase accumulator output will skip some RAM addresses automatically sampling the data stored in RAM Therefore as the output frequency is increased the number of output samples per waveshape cycle will decrease In fact different groups of points may be output on successive waveform cycles PIR k Phase ATX E Increment S ADDR aa Register d MSB s l Time 48Bit ES 48 Bit 14 Bits Clock Cycles J Ne p 4 ZN M Phase PIR 2k Register al
46. e The maximum external FSK rate is 1 MHz e The Ext annunciator turns on when the function generator is waiting for an external trigger signal FSKey SOURCe Query the internal FSK source Returns INT or EXT FSKey STATe OFF ON Disable or enable FSK modulation To ensure proper operation you should enable FSK after you have set up the other modulation parameters Only one modulation mode can be enabled at a time When you enable FSK the previous modulation mode is turned off FSKey STATe Query the state of the FSK mode Returns 0 OFF or 1 ON 169 Chapter 4 Remote Interface Reference Frequency Sweep Commands Frequency Sweep Commands See also Frequency Sweep starting on page 94 in chapter 3 Sweep Overview The following is an overview of the steps required to generate a frequency sweep The commands used for frequency sweep are listed on the next page Select the waveform shape amplitude and offset Use the APPLy command or the equivalent FUNC SHAP VOLT and VOLT OFFS commands to select the function amplitude and offset of the sweep waveform You can select a sine square triangle ramp or arbitrary waveform Select the start and stop frequencies Use the FREQ STAR and FREQ STOP commands to set the start and stop frequencies respectively To sweep up in frequency set the start frequency lt stop frequency To sweep down in frequency set the start frequen
47. e When the single or external trigger source is selected triggered mode the burst count and burst phase remain in effect but the burst rate is ignored e When the external gate burst source is selected gated burst mode the burst count burst rate burst phase and burst trigger source are ignored these parameters are used for the triggered burst mode only e It is possible to specify a burst rate which is too fast for the function generator to output with the specified carrier frequency and burst count If the burst rate is too high the function generator will internally adjust it as needed to continuously re trigger the burst The adjustment is handled internally by the function generator the burst rate displayed or queried will be the same as specified e Front Panel Operation 5 BURST RATE MOD MENU e Remote Interface Operation BM INTernal RATE lt frequency gt MINimum MAXimum 88 Chapter 3 Features and Functions Burst Modulation Burst Phase The burst phase defines the starting phase of the burst Burst phase 360 degrees to 360 degrees in 0 001 degree increments The default is 0 degrees For sine square triangle and ramp waveforms 0 degrees is the point at which the waveform crosses zero volts or the dc offset value in a positive going direction For arbitrary waveforms 0 degrees is the first data point downloaded to memory When the external gate source is
48. enable value SRE STB TRG TST WAI Default parameters are shown in bold 135 First time SCPI users see page 211 Chapter 4 Remote Interface Reference Simplified Programming Overview Simplified Programming Overview This section gives an overview of the basic techniques used to program the function generator over the remote interface This section is only an overview and does not give all of the details you will need to write your own application programs Refer to the remainder of this chapter and also chapter 6 Application Programs for more details and examples Also refer to the programming reference manual that came with your computer for details on outputting command strings and entering data Using the APPLy Command The APPLy command provides the most straightforward method to program the function generator over the remote interface For example the following statement executed from your computer will output a 3 Vpp sine wave at 5 kHz with a 2 5 volt offset APPL SIN 5 0E 3 3 0 2 5 Using the Low Level Commands Although the APPLy command provides the most straightforward method to program the function generator the low level commands give you more flexibility to change individual parameters For example the following statements executed from your computer will output a 3 Vpp sine wave at 5 kHz with a 2 5 volt offset FUNC SHAP SIN Select sine wave functi
49. frequency Set the modulating frequency to any value between 10 mHz and 20 kHz using the AM INT FREQ command Set the modulation depth Set the modulation depth to a value between 0 and 120 using the AM DEPT command Select the modulation source The function generator will accept an internal modulating signal an external modulating signal or both Select the modulating source using the AM SOUR command Enable AM modulation After you have set up the other modulation parameters use the AM STAT ON command to enable AM 154 Chapter 4 Remote Interface Reference AM Modulation Commands AM Commands Use the APPLy command or the equivalent FUNC SHAP FREQ VOLT and VOLT OFFS commands to configure the carrier waveform Set the carrier frequency between 100 uHz and 15 MHz 100 kHz for triangle and ramp The default is 1 kHz AM DEPTh depth in percent MINimum MAXimum Set the internal modulation depth in percent Select from 0 to 120 The default is 100 MIN 0 MAX 120 Stored in volatile memory If you select the external modulating source AM SOUR EXT the modulation depth is controlled by the signal level present on the AM Modulation terminal 5 volts peak corresponds to 10096 modulation AM DEPTh MINimum MAXimum Query the modulation depth Returns a value in percent AM INTernal FUNCtion SINusoid SQUare TRIangle RAMP NOISe USER Select the shape of the modul
50. front panel menus 26 Chapter 1 Quick Start To rack mount the function generator To rack mount the function generator You can mount the function generator in a standard 19 inch rack cabinet using one of three optional kits available Instructions and mounting hardware are included with each rack mounting kit Any Agilent System IT instrument of the same size can be rack mounted beside the 33120A Function Generator Remove the carrying handle and the front and rear rubber bumpers before rack mounting the function generator ll gt nunmnuuuug UI EM opo00000 To remove the handle rotate it to the vertical position and pull the ends outward l BN Op eem mene EN NANA IHR A 4 o ummug nmn EX LLL Pes Se Pa ed ole in Q j sib oooooOoOo0g J Le i Front Rear bottom view To remove the rubber bumper stretch a corner and then slide it off 27 Chapter 1 Quick Start To rack mount the function generator LI a SEE santay va Gree 5 O opo5000000 C C Samoan PIE ae LI dp santay vo Gree UL E3C3C 3 03 C3 CJ EE JE 3 1 3733 o ERES E3 E93 P3 F3 3 fo o BO0O0OOOOCO TE oO rt oO To rack mount two instruments side by sid
51. generator uses two handshake lines DTR Data Terminal Ready on pin 4 and DSR Data Set Ready on pin 6 The following sections contain information to help you use the function generator over the RS 232 interface The programming commands for RS 232 are listed on page 200 RS 232 Configuration Overview Configure the RS 232 interface using the parameters shown below Use the front panel I O MENU to select the baud rate parity and number of data bits see also pages 219 and 220 for more information e Baud Rate 300 600 1200 2400 4800 or 9600 baud factory setting e Parity and Data Bits None 8 data bits factory setting Even 7 data bits or Odd 7 data bits e Number of Start Bits 1 bit fixed e Number of Stop Bits 2 bits fixed To download binary data for arbitrary waveforms over the RS 232 interface you must select 8 data bits with no parity 195 Chapter 4 Remote Interface Reference RS 232 Interface Configuration RS 232 Data Frame Format A character frame consists of all the transmitted bits that make up a single character The frame is defined as the characters from the start bit to the last stop bit inclusively Within the frame you can select the baud rate number of data bits and parity type The function generator uses the following frame formats for seven and eight data bits PARITY EVEN ODD PARITY NONE Sort NS Stop Stop Connection to a Computer or Termina
52. generator can output five standard waveforms including sine square triangle ramp and noise You can also select one of five predefined arbitrary waveforms or download your own custom waveforms You can internally modulate any of the standard waveforms including arbitrary using AM FM FSK or burst modulation Linear or logarithmic frequency sweeping is available for any of the standard waveforms except noise and arbitrary waveforms The default function is sine wave e Possible Conflict with Output Frequency The output frequency is automatically adjusted if you select a function whose maximum frequency is less than that of the currently active function For example if you output a 1 MHz sine wave and then change the function to triangle wave the function generator will adjust the output to 100 kHz the upper limit for triangle waves From the front panel FREQ LIMIT is displayed and the frequency is adjusted From the remote interface a 221 Settings conflict error is generated and the frequency is adjusted e Possible Conflict with Output Amplitude The output amplitude is automatically adjusted if you select a function whose maximum amplitude is less than that of the currently active function This conflict may arise when the output units are Vrms or dBm due to the differences in crest factor for the output functions For example if you output a 5 Vrms square wave into 50 ohms and then change the function to sin
53. invalid for the presently selected function Cal signal measurement out of range The specified calibration value CAL VALUE does not match the signal applied to the function generator Flatness cal failed Cannot calibrate frequency while externally locked You cannot perform CAL SETUP 0 or CAL SETUP 86 while the function generator is externally phase locked Option 001 RAM checksum failure 238 770 771 772 773 774 775 780 800 810 850 851 852 853 854 855 856 857 858 to 788 Chapter 5 Error Messages Calibration Errors Nonvolatile arb waveform memory checksum failure Nonvolatile cal memory checksum failure Nonvolatile system memory checksum failure Nonvolatile state memory checksum failure Nonvolatile memory erase failure Nonvolatile memory write failure See Arbitrary Waveform Errors on page 240 Block length must be even The function generator represents binary data for arbitrary waveforms as a 12 bit integers which is sent as two bytes DATA DAC VOLATILE command only An odd number of bytes is not accepted because the function generator would not know how to interpret the last single byte State has not been stored The memory location specified in the RCL command was not used in a previous SAV command You cannot recall the instrument state from a memory location that was not previous specified as a storage location Cal setup inva
54. line 1 kV line ground IEC 61000 4 6 1996 EN 61000 4 6 1996 SV 0 15 80 MHz I cycle 100 IEC 61000 4 11 1994 EN 61000 4 11 1994 Dips 30 10ms 60 100ms Interrupt gt 95 9 5000ms Canada ICES 001 1998 Australia New Zealand AS NZS 2064 1 The product was tested in a typical configuration with Agilent Technologies test systems Safety EC 61010 1 1990 A1 1992 A2 1995 EN 61010 1 1993 A2 1995 Canada CSA C22 2 No 1010 1 1992 UL 3111 1 1994 1 May 2001 Date Ray Corson Product Regulations Program Manager For further information please contact your local Agilent Technologies sales office agent or distributor Authorized EU representative Agilent Technologies Deutschland GmbH Herrenberger Strabe 130 D71034 B blingen Germany 309 Copyright Agilent Technologies Inc 1994 2002 No part of this manual may be repro duced in any form or by any means including electronic storage and retrieval or translation into a foreign language without prior agreement and written consent from Agilent Technologies as governed by the United States and international copyright laws Manual Part Number 33120 90006 March 2002 order as 33120 90104 manual set Edition Edition 6 March 2002 Edition 5 August 1997 Edition 4 February 1996 Edition 3 May 1994 Edition 2 March 1994 Edition 1 January 1994 Printed in Malaysia Agilent Technologies Inc 815 14th Street S W Loveland Colorado 80537 U S A Assistan
55. loop lt 4000 loop waveform loop 0 Set remaining points to zero Call function to download the 4000 data points to volatile memory download data waveform num points Free memory allocated for data points free waveform BK RK KK RR KK KR RK KR RK KR RR oko ko kckck kk ck ck ck ck ck ck RRR ck ck ck ck ck ck ck ck ck ok ok ok ok ke ke ke ke ke ke ke J void download data float waveform int num points Download the waveform array 4000 points to volatile memory The function generator expects to receive the arb waveform data as one contiguous block To do this suppress the carriage return CR and line feed LF before downloading the data static char state 2 13 10 ASCII 13 carriage return ASCII 10 line feed First disable EOI End or Identify and EOL End of Line IOEOI ISC 0 IOEOL ISC 0 Send DATA VOLATILE header and suppress CR LF printf Downloading Arb n n IOOUTPUTS ADDR DATA VOLATILE 14 Re enable EOI and EOL for normal GPIB operation and send the data IOEOI ISC 1 IOEOL ISC state 2 Use the IOOUTPUTA to output the waveform data as an ASCII array IOOUTPUTA ADDR waveform num points printf Download Complete n n Call the function to check for errors check error download data BK RK KKK KR RRR KR KK kk kk kk ck ck ck ck KKK kc kc kckck ck ck c
56. mHz MAX 10 kHz Stored in volatile memory FM INTernal FREQuency MINimum MAXimum Query the modulating frequency Returns a value in hertz FM STATe OFF ON Disable or enable FM To ensure proper operation you should enable FM after you have set up the other modulation parameters Only one modulation mode can be enabled at a time When you enable FM the previous modulation mode is turned off FM STATe Query the state of FM Returns 0 OFF or 1 ON 159 Chapter 4 Remote Interface Reference Burst Modulation Commands Burst Modulation Commands See also Burst Modulation starting on page 81 in chapter 3 Burst Modulation Overview The following is an overview of the steps required to generate a burst modulated waveform The commands used for burst modulation are listed on page 162 You can use burst modulation in the following two modes The function generator enables one burst mode at a time based on the trigger source and burst source that you select see the table below e Triggered Burst Mode In this mode the function generator outputs a waveform with a specified number of cycles burst count each time a trigger is received After the specified number of cycles has been output the function generator waits for the next trigger You can configure the function generator to accept an internal trigger or you can send the trigger externally by pressing the front panel Single key o
57. no load and the terminated output voltage loaded The terminated output amplitude is calibrated for an exact 50 ohm load Since the function generator s output resistance and the load resistance form a voltage divider the measured output voltage of the function generator will vary with load resistance value and accuracy When the function generator s output is loaded with a 0 2 accuracy termination an additional negligible 0 2 amplitude error is created Using a 5 accuracy termination will add 5 additional error to specified output amplitudes 500 vgen A gt 500 Vload If the function generator s output is measured with no load connected the output will be approximately twice the displayed amplitude Vgen instead of Vioad In some applications you might continually use the function generator in a no load conditions In such applications remembering to double the function generator s displayed amplitude can cause many errors The 33120A allows you to specify the function generator s load condition using the OUTPUT LOAD command thus enabling the function generator to display the correct output amplitude 281 Chapter 7 Tutorial Floating Signal Generators Floating Signal Generators Many applications require a test signal which is isolated from earth ground for connection to powered circuits to avoid ground loops or to minimize other common mode noise A floating signal generator such as the 3312
58. number of cycles called a burst You can output the burst at a rate determined by the internal rate generator or the signal level on the rear panel Ext Trig terminal For this example you will output a three cycle sine wave You will not change the other parameters from their default settings internal burst source 0 degree starting phase and 100 Hz burst rate N 1 Select the function frequency and amplitude for the burst For bursts you can select sine square triangle ramp or arbitrary waveforms For this example select a 1 kHz sine wave with an output amplitude of 5 Vpp Shift Burst 2 Enable the burst mode Notice that the Burst annunciator turns on Shift 3 Use the menu to set the burst count Recall Menu After you enable the burst mode the recall menu key will automatically take you to the BURST CNT command in the MOD MENU 4 BURST CNT 47 Chapter 2 Front Panel Menu Operation To output a burst waveform v 4 Move down to the parameter level and set the count to 3 Notice that the Burst annunciator flashes indicating that the displayed parameter is for the burst mode For more information on editing numbers in the menu refer to Menu Example 3 earlier in this chapter 00003 CYC You can also select an infinite burst count Press the right or left arrow keys until the CYC units are flashing Then press the down arrow key
59. ohms and then change the function to sine wave the function generator will adjust the output amplitude to 3 535 Vrms the upper limit for sine waves in Vrms From the front panel AMPL LIMIT is displayed and the amplitude is adjusted From the remote interface a 221 Settings conflict error is generated and the amplitude is adjusted 59 Output Amplitude continued Chapter 3 Features and Functions Output Configuration Output Amplitude and Output Termination The output amplitude is automatically adjusted and no error is generated if you change the output termination For example if you set the amplitude to 10 Vpp and then change the termination from 50 ohms to high impedance the displayed amplitude will double to 20 Vpp If you change from high impedance to 50 ohms the displayed amplitude will drop in half See Output Termination on page 65 for more information Offset Voltage Restrictions The output amplitude in Vpp and the dc offset voltage must obey the following restrictions If the specified amplitude is not valid the function generator will automatically adjust it to the maximum value allowed with the present offset voltage Vmax is either 10 volts for a high impedance termination or 5 volts for a 50 ohm termination Vpp is the output amplitude in volts peak to peak V Voffset E lt Vmax and Voffset lt 2x Vpp From the front panel MAX VALUF is displayed and the amplitu
60. operation is otherwise unaffected by turning off the display The display state is stored in volatile memory the display is always enabled when power has been off or after a remote interface reset You can display a message on the front panel by sending a command from the remote interface The function generator can display up to 11 characters of the message on the front panel any additional characters are truncated Commas periods and semicolons share a display space with the preceding character and are not considered individual characters When a message is displayed information relating to the output waveform such as frequency and amplitude is not sent to the display Sending a message to the display from the remote interface overrides the display state this means that you can display a message even if the display is turned off The display state is automatically turned on when you return to the local front panel state Press the Shift key or execute LOCAL 710 from the remote interface to return to the local state Remote Interface Operation DISPlay OFF ON Disable enable the display DISPlay TEXT lt quoted string gt Display the string enclosed in quotes DISPlay TEXT CLEar Clear the displayed message The following command string shows how to display a message on the front panel DISP TEXT HELLO 112 Chapter 3 Features and Functions System Related Operati
61. output continuously at a rate determined by the burst rate setting The burst rate frequency defines the interval between bursts e When the single or external trigger source is selected the burst count and burst phase remain in effect but the burst rate is ignored The specified number of cycles is output each time Single is pressed or when a trigger signal is applied to the Ext Trig terminal The function generator is triggered on the rising edge of a TTL pulse e When the external gate burst source is selected the burst count burst rate burst phase and burst trigger source are ignored these parameters are used for the triggered burst mode only e Front Panel Operation 4 BURST CNT MOD MENU e Remote Interface Operation BM NCYCles lt cycles gt INFinity MINimum MAXimum 87 Chapter 3 Features and Functions Burst Modulation Burst Rate The burst rate defines the frequency at which internally triggered bursts are generated The burst rate frequency defines the interval between bursts Used only in the internal triggered burst mode Keep in mind that the burst rate is different than the carrier frequency which specifies the frequency of the bursted signal e Burst rate 10 mHz to 50 kHz The default is 100 Hz e The burst rate setting is used only when internal triggering is enabled triggered mode The burst rate is ignored when single triggering or external triggering is enabled
62. output units are remembered For example if you select Vrms from the remote interface the units are shown as Vrms on the front panel display The default is VPP Stored in volatile memory VOLTage UNIT Query the units selected Returns VPP VRMS or DBM 150 Chapter 4 Remote Interface Reference Output Configuration Commands OUTPut LOAD 50 INFinity MINimum MAXimum Select the output termination for output amplitude and offset voltage The function generator has a fixed output impedance of 50 ohms on the OUTPUT terminal You can specify whether you are terminating the output into a 50 ohm load or an open circuit Incorrect impedance matching between the function generator and your load will result in an amplitude or offset which does not match the specified signal level Stored in volatile memory e INF sets the output termination to high impedance MIN selects 50Q MAX selects high impedance The default is 50 e The amplitude or dc offset is automatically adjusted and no error is generated if you change the output termination For example if you set the amplitude to 10 Vpp and then change the termination from 50 ohms to high impedance the displayed amplitude will double to 20 Vpp If you change from high impedance to 50 ohms the displayed amplitude will drop in half e Ifyou specify a 50 ohm termination but are actually terminating into an open circu
63. queue If no errors have occurred when you read the error queue the function generator responds with 0 No error e The error queue is cleared when power has been off or after a CLS clear status command has been executed The RST reset command does not clear the error queue e Errors have the following format the error string may contain up to 80 characters 113 Undefined header 189 Chapter 4 Remote Interface Reference System Related Commands SYSTem VERSion Query the function generator to determine the present SCPI version Returns a string in the form YYYY V where the Y s represent the year of the version and the V represents a version number for that year for example 1993 0 IDN Read the function generator s identification string The function generator returns four fields separated by commas The first field is the manufacturer s name the second field is the model number the third field is not used always 0 and the fourth field is a revision code which contains three numbers The first number is the firmware revision number for the main generator processor the second is for the input output processor and the third is for the front panel processor e The command returns a string with the following format be sure to dimension a string variable with at least 40 characters HEWLETT PACKARD 33120A 0 X X X X X X RST Reset the function generator to its default
64. right through the choices on each level of the menu A o Shift AM Shift Recall Menu Chapter 2 Front Panel Menu Operation To output a modulated waveform To output a modulated waveform A modulated waveform consists of a carrier and a modulating waveform In AM amplitude modulation the amplitude of the carrier is varied by the amplitude of the modulating waveform For this example you will output an AM waveform with 80 modulation depth The carrier will be a 5 kHz sine wave and the modulating waveform will be a 200 Hz sine wave Select the function frequency and amplitude of the carrier For the carrier waveform you can select a sine square triangle ramp or arbitrary waveform For this example select a 5 kHz sine wave with an amplitude of 5 Vpp Select AM Notice that the AM annunciator turns on Use the menu to select the shape of the modulating waveform After you enable the AM function the recall menu key will automatically take you to the AM SHAPE command in the MOD MENU 41 Enter Shift Freq 6 Chapter 2 Front Panel Menu Operation To output a modulated waveform Move down a level and verify that SINE is selected For the modulating waveform you can select a sine square triangle ramp noise or arbitrary waveform For this example you will modulate the carrier with a sine waveform Notice that
65. start frequency The default is IMM Stored in volatile memory e When the Immediate internal source is selected the function generator outputs a continuous sweep at a rate determined by the sweep rate specified SWE TIME The APPLy command automatically sets the trigger source to IMMediate e When the External source is selected the function generator will accept a hardware trigger applied to the rear panel Ext Trig terminal The function generator outputs one sweep each time each time Ext Trig receives the rising edge of a TTL pulse The Trig annunciator turns on when the function generator is waiting for an external trigger e When the Bus software source is selected the function generator outputs one sweep each time a bus trigger command is received To trigger the function generator from the remote interface GPIB or RS 232 send the TRG trigger command e To ensure synchronization when the Bus source is selected send the WAI wait command When the WAI command is executed the function generator waits for all pending operations to complete before executing any additional commands For example the following command string guarantees that the first trigger is accepted and executed before the second trigger is recognized TRIG SOUR BUS TRG WAI TRG WAI 172 Chapter 4 Remote Interface Reference Frequency Sweep Commands e You can use the OPC operation complete query comman
66. that location From the remote interface a 810 State has not been stored error is generated if nothing is stored in the specified memory location MEMory STATe DELete 0 1 2 3 Delete a previously stored state and clear the memory location If nothing is stored in the specified memory location a 810 State has not been stored error is generated OPC Set the operation complete bit bit 0 in the Standard Event register after the previous commands have been executed Used only in the triggered burst mode and triggered sweep mode OPC Return 1 to the output buffer after the previous commands have been executed Used only in the triggered burst mode and triggered sweep mode WAI Wait for all pending operations to complete before executing any additional commands over the interface Used only in the triggered burst mode and triggered sweep mode 192 Chapter 4 Remote Interface Reference Calibration Commands Calibration Commands See Calibration Overview starting on page 118 for an overview of the calibration features of the function generator For a more detailed discussion of the calibration procedures see chapter 4 in the Service Guide CALibration Perform a calibration using the specified calibration value CAL VAL command Before you can calibrate the function generator you must unsecure it by entering the correct security code CALibration COUNt Query the function generator
67. the function generator IF PCIB ERR NOERR THEN ERROR PCIB BASERR CALL IOREMOTE Dev amp Place the function generator in the remote mode IF PCIB ERR NOERR THEN ERROR PCIB BASERR Infol1 RST Reset the function generator Length1 LEN Info1 CALL IOOUTPUTS Dev amp Infol Length1 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR Infol S OUTP LOAD 50 Output termination is 50 ohms Length1 LEN Info1 CALL IOOUTPUTS Dev amp Infol Length1 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR Infol S FUNC SHAP SIN Carrier waveshape is sine wave Length1 LEN Info1 CALL IOOUTPUTS Dev amp Infol Length1 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR Infol FREQ 5000 VOLT 5 Carrier frequency is 5 kHz 5 Vpp Length1 LEN Info1 CALL IOOUTPUTS Dev amp Infol Length1 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASE 5 258 Chapter 6 Using the continued Infol AM INT FUNC SIN Length1 LEN Info1 Application Programs Low Level Commands Modulating waveshape is sine wave CALL IOOUTPUTS Dev amp Infol Length1 IF PCIB ERR NOERR THEN ERROR PCIB BASERR Infol1 AM INT FREQ 200 Length1 LEN Info1 Modulating fre
68. to display INFINITE Enter 5 Save the change and turn off the menu The function generator beeps and displays a message to show that the change is now in effect You are then exited from the menu ENTERED At this point the function generator outputs a continuous three cycle burst You can generate a single burst with the specified burst count by pressing the Single key from the front panel or applying a trigger pulse to the rear panel Ext Trig terminal For more information see To trigger a burst or sweep on page 51 You can also use an external gate signal to turn the output signal on and off For more information see Burst Modulation in chapter 3 48 Shift Sweep Shift lt Recall Menu en 2 Chapter 2 Front Panel Menu Operation To output a frequency sweep To output a frequency sweep In the frequency sweep mode the function generator steps from the start frequency to the stop frequency at a sweep rate which you specify You can sweep up or down in frequency and with either linear or logarithmic spacing For this example you will output a swept sine wave from 50 Hz to 5 kHz You will not change the other parameters from their default settings internal sweep trigger linear spacing and 1 second sweep time Select the function and amplitude for the sweep For sweeps you can select sine square triangle ramp or arbitrary
69. when power is restored The recall mode is disabled when the function generator is shipped from the factory Select the POWER ON LAST STATE command from the SYS MENU to enable the power down recall mode Select POWER ON DEFAULT to disable the power down recall mode See Power Down Recall Mode on page 109 for more information From the remote interface you can use memory location 0 to store a fourth instrument configuration you cannot store to this memory location from the front panel However keep in mind that memory location 0 is automatically overwritten when the power is turned off Front Panel Operation To store the state press Shift Store Then use the knob arrow keys or Enter Number mode to select the memory location To restore the state press Recall Then use the knob arrow keys or Enter Number mode to select the memory location Remote Interface Operation SAV 0 1 2 3 State 0 is the instrument state at power down RCL 0 1 2 3 States 1 2 and 3 are user defined states From the remote interface you can delete individual stored states and clear the memory location If nothing is stored in the specified memory location a 810 State has not been stored error is generated MEMory STATe DELete 0 1 2 3 70 Chapter 3 Features and Functions Amplitude Modulation AM Amplitude Modulation AM A modulated waveform consists of
70. 0 158 frequency sweep See sweep frequency arb waveform limits 57 146 conflict with duty cycle 58 147 conflict with function 58 146 front panel selection 19 limits 57 146 modulation 76 157 remote interface selection 57 146 frequency shift keying See FSK front panel annunciators 5 dc volts selection 24 downloading waveforms 103 108 menu examples 33 39 menu messages 34 menu reference 31 32 number entry 3 38 overview 2 front panel display annunciators 5 enable disable 112 188 text message 112 188 FSK annunciator 5 FSK terminal 102 FSK carrier frequency 91 front panel operation 44 hop frequency 92 168 internal rate 93 168 maximum external rate 93 operational overview 167 source 93 169 sync signal 91 technical description 290 FSK FREQ command 168 FSK INT RATE command 168 FSK SOUR command 169 FSK STAT command 169 FUNC SHAP command 145 FUNC SHAP USER command 177 FUNC USER command 176 function conflict with amplitude 55 conflict with frequency 55 front panel selection 56 modulation matrix 56 145 remote interface selection 145 fuse power line 16 G gate source burst modulation 164 gated burst mode 81 160 GPIB arb waveform download 255 capability codes 225 download speeds 299 selecting interface 115 218 GPIB address factory setting 114 217 selecting 114 217 GPIB Command Library 244 ground loops 282 ground ch
71. 00 mV peak to peak 50Q termination You can also use the knob to scroll left or right through the choices on each level of the menu 36 Menu Example 2 Shift lt Recall Menu Enter Chapter 2 Front Panel Menu Operation A front panel menu tutorial The following example shows how to use the recall menu feature as a shortcut to set the POWER ON command back to its original setting You must perform the steps in Example 1 before you start this example Use recall menu to return to the POWER ON command This returns you to the POWER ON command which was the last command used before you exited the menu in the Example 1 2 POWER ON Move down to the PARAMETER choices The first parameter choice is LAST STATE the current setting from LAST STATE le e iS 5 ke S far Move across to the DEFAULT choice 1 Set the parameter back to its original value DEFAULT Save the change and turn off the menu The function generator beeps and displays a message to show that the change is now in effect You are then exited from the menu ENTERED You can also use the knob to scroll left or right through the choices on each level of the menu 37 Menu Example 3 Shift Menu On Off en 1 Chapter 2 Front Panel Menu Operation A front panel menu tutorial Some commands in the menu require that you enter a numeric parameter v
72. 000 000 0 KHz Enter the magnitude of the desired frequency Notice that the Num annunciator turns on and ENTER NUM flashes on the display indicating that the number mode is enabled m N To cancel the number mode press Shift Cancel Set the units to the desired value The units are selected using the arrow keys on the right side of the front panel As soon as you select the units the function generator outputs the waveform with the displayed frequency To turn off the flashing digit move the cursor to the left of the display using the arrow keys 1 200 000 0 MHz You can also use the knob and arrow keys to enter a number See Front Panel Number Entry on page 3 for more information 19 Ampl Enter Number 5 q Shift kHz m Vrms In 2 HG Chapter 1 Quick Start To set the output amplitude To set the output amplitude At power on the function generator outputs a sine wave with an amplitude of 100 mV peak to peak into a 50Q termination The following steps show you how to change the amplitude to 50 mVrms Enable the amplitude modify mode The displayed amplitude is either the power on value or the previous amplitude selected When you change functions the same amplitude is used if the present value is valid for the new function 100 0 mVPP Enter the magnitude of the desired amplitude 91 Notice that the Num annunciator turns on and
73. 0A has both sides of the output BNC connector isolated from chassis earth ground As shown in the figure below any voltage difference between the two ground reference points Vground causes a current to flow through the function generator s output common lead This can cause errors such as noise and offset voltage usually power line frequency related which are added to the output voltage The best way to eliminate ground loops is to maintain the function generator s isolation from earth ground The function generator s isolation impedance will be reduced as the frequency of the Vground source increases due to low to earth capacitance Cle approximately 4000 pF for the 33120A If the function generator must be earth referenced be sure to connect it and the load to the same common ground point This will reduce or eliminate the voltage difference between devices Also make sure the function generator and load are connected to the same electrical outlet if possible RL 500 S JE TS Load Van lt N E M Common Pd f re Oe Z Ri 10G0 V p z ground Pd JEN 7 SOS Nu Ne R Lead Resistance 282 Chapter 7 Tutorial Attributes of AC Signals Attributes of AC Signals The most common ac signal is the sine wave In fact all periodic waveshapes are composed of sine waves of varying frequency amplitude and phase added together The individual sine waves are harmonically related to each othe
74. 1 speeds arb waveforms GPIB 299 arb waveforms RS 232 299 standard event register bit definitions 207 clearing bits 208 start bits RS 232 195 start frequency sweeps 95 171 starting phase bursts 89 163 state storage delete state 153 192 example program 252 front panel operation 25 power down recall 109 recalling stored state 153 192 remote interface operation 152 state power on and reset 123 status byte bit definitions 203 clearing bits 203 status registers 201 208 example program 261 register diagram 202 standard event 207 status byte 203 stop bits RS 232 195 stop frequency sweeps 95 171 stored states delete state 153 192 example program 252 front panel operation 25 power down recall 109 recalling stored state 153 192 remote interface operation 152 307 Index string calibration 122 display message 112 swapped byte order 185 SWE SPAC command 172 SWE TIME command 172 sweep front panel operation 49 94 linear spacing 96 172 logarithmic spacing 96 172 remote interface operation 170 start frequency 95 171 stop frequency 95 171 sweep time 96 172 sync signal 95 technical description 289 trigger source 97 173 Swp annunciator 5 sync signal AM 74 burst gated mode 86 burst triggered mode 86 enabling disabling 68 151 FM 79 for all functions 68 FSK 91 sweep 95 SYNC terminal 68 151 syntax colon vs semicolon 213 SCPI conv
75. 149 VOLTage OFFSet continued Chapter 4 Remote Interface Reference Output Configuration Commands e DC Offset and Output Termination The offset voltage is auto matically adjusted and no error is generated if you change the output termination For example if you set the offset to 100 mVdc and then change the termination from 50 ohms to high impedance the displayed offset will double to 200 mVdc If you change from high impedance to 50 ohms the displayed offset will drop in half See the OUTP LOAD command for more information e For dc volts the output level is actually controlled by setting the offset voltage You can set the dc voltage to any value between 5 Vdc into 50 ohms or 10 Vdc into an open circuit e For arbitrary waveforms the Offset annunciator will turn on if the waveform data has an inherent offset present if the average is not equal to zero The function generator calculates the average of the data points and compares the average to zero volts If the average is not within two DAC Digital to Analog Converter counts of zero volts the Offset annunciator turns on VOLTage OFFSet MINimum MAXimum Query the dc offset voltage for the currently selected function Returns a value in dc volts VOLTage UNIT VPP VRMS DBM DEFault Select the output units for amplitude only does not affect offset When switching from remote programming over the interface back to front panel local operation the
76. 193 for more information CALibration CALibration COUNt CALibration SECure CODE lt new code gt CALibration SECure STATe OFF ON lt code gt CALibration SECure STATe CALibration SETup 0 1 2 3 84 gt CALibration SETup CALibration STRing quoted string CALibration STRing CALibration VALue value CALibration VALue RS 232 Interface Commands see page 200 for more information SYSTem LOCal SYSTem REMote SYSTem RWLock Default parameters are shown in bold 133 Chapter 4 Remote Interface Reference SCPI Command Summary Status Reporting Commands see page 209 for more information SYSTem ERRor Output Buffer Binary Weights CLS ESE lt enable value gt ESE Standard Event fer Enable Register ESR OPC OPC PSC 0 1j ESR ESE value PSC M SRE enable value SRE STB WAI Default parameters are shown in bold 134 Chapter 4 Remote Interface Reference SCPI Command Summary IEEE 488 2 Common Commands see page 209 for more information CLS ESE enable value ESE ESR IDN OPC OPC PSC 0 1 PSC RST SAV 0 1 2 3 State 0 is the instrument state at power down RCL 0 1 2 3 States 1 2 and 3 are user defined instrument states L SRE
77. 2 Chapter 4 Remote Interface Reference SCPI Conformance Information Device Specific Commands The following commands are designed specifically for the 33120A They are not included in the 1993 0 version of the SCPI standard However these commands are designed with the SCPI standard in mind and they follow all of the command syntax rules defined by the standard Non SCPI Commands CALibration COUNT SECure CODE new code SECure STATe OFF ON lt code gt SECure STATe 1 2 3 84 gt STRing quoted string STRing ATTRibute AVERage arb name ATTRibute CFACtor arb name ATTRibute POINts arb name gt ATTRibute PTPeak arb name DAC VOLATILE binary block value value NVOLatile CATalog NVOLatile FREE OUTPut LOAD 50 INFinity MINimum MAXimum LOAD MINimum MAXimum SYNC OFF ON SYNC MEMory STATe DELete 0 1 2 3 SOURce AM INTernal FUNCtion SINusoid SQUare TRIangle RAMP NOISe USER AM INTernal FUNCtion APPLy SINusoid lt frequency gt lt amplitude gt lt offset gt 1 APPLy SQUare lt frequency gt lt amplitude gt lt offset gt APPLy TRIangle lt frequency gt lt amplitude gt lt offset gt APPLy RAMP lt frequency gt lt amplitude gt lt offset gt APPLy NOISe lt frequency DEFault gt lt amplitude gt lt offset gt
78. 4 Remote Interface Reference Using the APPLy Command Using the APPLy Command See also Output Configuration starting on page 55 in chapter 3 The APPLy command provides the most straightforward method to program the function generator over the remote interface You can select the function frequency amplitude and offset all in one command For example the following statement outputs a 3 Vpp sine wave at 5 kHz with a 2 5 volt offset using APPLy APPL SIN 5 KHZ 3 0 VPP 2 5 V The syntax statements for the APPLy command are shown on page 143 Output Frequency e For the frequency parameter of the APPLy command the output frequency range depends on the function currently selected You can substitute MINimum MAXimum or DEFault in place of a specific value for the frequency parameter MIN selects the lowest frequency allowed for the selected function MAX selects the highest frequency allowed The default frequency for all functions is 1 kHz Function Minimum Frequency Maximum Frequency Sine 100 uHz 15 MHz Square 100 uHz 15 MHz Ramp 100 Hz 100 kHz Triangle 100 uHz 100 kHz Built In Arbs 1 100 Hz 5 MHz 1 There are five built in arbitrary waveforms stored in non volatile memory sinc negative ramp exponential rise exponential fall and cardiac 138 Chapter 4 Remote Interface Reference Using the APPLy Command e For arbitrary waveforms that you create and download to memory
79. 43 Chapter 4 Remote Interface Reference Using the APPLy Command APPLy NOISe frequency DEFault lt amplitude gt lt offset gt 11 Output noise with the specified amplitude and dc offset The waveform is output as soon as the command is executed e The frequency parameter is ignored for this command but you MUST specify a value or DEF If you specify a frequency the value is remembered when you change to a different function For example APPL NOIS DEF 5 0 2 0 APPLy DC frequency DEFault amplitude DEFault offset 11 Output a dc voltage with the level specified by the offset parameter The dc voltage is output as soon as the command is executed e The frequency and amplitude parameters are ignored for this command but you MUST specify a value or DEF If you specify a frequency and amplitude the values are remembered when you change to a different function For example APPL DC DEF DEF 2 5 APPLy USER frequency lt amplitude gt offset 11 Output the arbitrary waveform currently selected by the FUNC USI command The waveform is output using the specified frequency amplitude and dc offset The waveform is output as soon as the command is executed Ei See Arbitrary Waveform Commands on page 174 for more information on downloading arbitrary waveforms to memory APPLy Query the function generator s present configuration and return a quoted string The f
80. 5 269 270 Tutorial Tutorial The Agilent 33120A is capable of producing a variety of signal waveshapes In order to achieve the greatest performance from the function generator it may be helpful if you learn more about the internal operations of the instrument This chapter describes basic signal generation concepts and gives specific details on the internal operations of the function generator e Direct Digital Synthesis starting on page 273 e Signal Imperfections starting on page 276 e Creating Arbitrary Waveforms starting on page 278 e Output Amplitude Control starting on page 280 e Floating Signal Generators on page 282 e Attributes of AC Signals starting on page 283 e Modulation starting on page 287 You can use an arbitrary waveform generator in a variety of applications where it might be otherwise difficult or impossible to generate complex output waveforms With an arbitrary waveform generator signal imperfections such as rise time ringing glitches noise and random timing variations can be easily simulated in a controlled manner Physics chemistry biomedicine electronics mechanics and other fields can benefit from the versatility of an arbitrary waveform generator Wherever things vibrate pump pulse bubble burst or change with time in any way there are possible applications limited only by your ability to provide waveform data The Agilent IntuiLink Arb Waveform Generation
81. 50 when power has been off or after a remote interface reset The APPLy command automatically sets the duty cycle to 50 for square waves e Before attempting to set the duty cycle you must enable the square wave function From the front panel SQUARE ONLY is displayed if square wave is not currently active From the remote interface no error is generated but the specified duty cycle is remembered when you change to the square wave function e The duty cycle setting is remembered when you change from square wave to another function When you return to the square wave function the previous duty cycle is used 66 Chapter 3 Features and Functions Output Configuration e Possible Conflict with Output Frequency The duty cycle is auto matically adjusted if you select a frequency that is not valid with the present duty cycle For example if you set the duty cycle to 70 and then change the frequency to 8 MHz the function generator will automatically adjust the duty cycle to 60 the upper limit for this frequency From the front panel DUTY LIMIT is displayed and the duty cycle is adjusted From the remote interface a 221 Settings conflict error is generated and the duty cycle is adjusted e Front Panel Operation To set the duty cycle press Shift Duty the value appears on the display for approximately 10 seconds Then use the knob arrow keys or Enter Number mode to set the duty cycl
82. AMP NOISe USER Modulating Waveform Frequency The function generator will accept only an internal modulating signal e Modulating frequency internal source 10 mHz to 10 kHz The default is 10 Hz e The sync signal for FM is referenced to the modulating signal not the carrier momentary TTL high pulse gt 200 ns is output at each zero crossing point of the modulating signal The signal is output from the front panel SYNC terminal e Front Panel Operation Press Shift Freq to set the modulating frequency the value is displayed for approximately 10 seconds Before setting the modulating frequency from the front panel you must have FM enabled If you attempt to set the frequency when FM is not enabled SELECT AM FM is displayed e Remote Interface Operation FM INTernal FREQuency lt frequency gt MINimum MAXimum 79 Chapter 3 Features and Functions Frequency Modulation FM Peak Frequency Deviation The peak frequency deviation represents the variation in frequency of the modulating waveform from the carrier frequency Peak frequency deviation 10 mHz to 7 5 MHz The default is 100 Hz The carrier frequency must always be greater than or equal to the peak frequency deviation If you attempt to set the deviation to a value greater than the carrier frequency with FM enabled the function generator will automatically adjust the deviation to equal the present carrier freque
83. Byte using an IEEE 488 serial poll or by reading the event register whose summary bit is causing the service request To read the Status Byte summary register send the IEEE 488 serial poll message Querying the summary register will return a decimal value which corresponds to the binary weighted sum of the bits set in the register Serial poll will automatically clear the request service bit in the Status Byte summary register No other bits are affected Performing a serial poll will not affect instrument throughput The IEEE 488 2 standard does not ensure synchronization between your bus controller program and the instrument Use the OPC command to guarantee that commands previously sent to the instrument have completed Executing a serial poll before a RST CLS or other commands have completed can cause previous conditions to be reported 204 Chapter 4 Remote Interface Reference The SCPI Status Registers Using STB to Read the Status Byte The STB status byte query command is similar to a serial poll but it is processed like any other instrument command The STB command returns the same result as a serial poll but the request service bit bit 6 is not cleared if a serial poll has occurred The STB command is not handled automatically by the IEEE 488 bus interface hardware and will be executed only after previous commands have completed Polling is not possible using the STB command Executing the
84. Change The output frequency is automatically adjusted if you select a function whose maximum frequency is less than that of the currently active function For example if you output a 1 MHz sine wave and then change the function to triangle wave the function generator will adjust the output to 100 kHz the upper limit for triangle waves From the remote interface a 221 Settings conflict error is generated and the frequency is adjusted FREQuency MINimum MAXimum Query the frequency setting for the function currently active Returns a value in hertz 146 Chapter 4 Remote Interface Reference Output Configuration Commands PULSe DCYCle lt percent gt MINimum MAXimum Set the duty cycle in percent for square waves only Duty cycle represents the amount of time per cycle that the square wave is high The default is 50 Stored in volatile memory e Duty cycle 20 to 80 in 1 increments frequency lt 5 MHz 40 to 60 in 1 increments frequency gt 5 MHz The default is 50 e The duty cycle setting is remembered when you change from square wave to another function When you return to the square wave function the previous duty cycle is used The APPLy command automatically sets the duty cycle to 50 for square waves e Possible Conflict with Output Frequency The duty cycle is auto matically adjusted if you select a frequency that is not valid with the present duty cycle For example if you set the duty c
85. Converter For example the built in SINC waveform does not use the full range of values between 1 and therefore its maximum amplitude is 6 084 Vpp into 50 ohms e You can set the units for output amplitude to Vpp Vrms or dBm See Output Units on page 64 for more information 140 Chapter 4 Remote Interface Reference Using the APPLy Command e Possible Conflict with Function Change The output amplitude is automatically adjusted if you select a function whose maximum amplitude is less than that of the currently active function This conflict may arise when the output units are Vrms or dBm due to the differences in crest factor for the output functions For example if you output a 5 Vrms square wave into 50 ohms and then change the function to sine wave the function generator will adjust the output amplitude to 3 535 Vrms the upper limit for sine waves in Vrms From the remote interface a 221 Settings conflict error is generated and the amplitude is adjusted e Output Amplitude and Output Termination The output amplitude is automatically adjusted and no error is generated if you change the output termination For example if you set the amplitude to 10 Vpp and then change the termination from 50 ohms to high impedance the displayed amplitude will double to 20 Vpp If you change from high impedance to 50 ohms the displayed amplitude will drop in half See Output Termination on pag
86. ER level to select the baud rate Use the left right arrow keys to see the baud rate choices Choose from one of the following 300 600 1200 2400 4800 or 9600 baud 9600 BAUD Save the change and exit the menu The baud rate selection is stored in non volatile memory and does not change when power has been off or after a remote interface reset 219 Shift ages Menu On Off Enter Chapter 4 Remote Interface Reference To set the parity To set the parity You can select the parity for RS 232 operation The function generator is configured for 8 data bits with no parity when shipped from the factory See also Parity Selection on page 116 Turn on the menu A MOD MENU Move across to the I O MENU choice on this level E I O MENU Move down a level and then across to the PARITY choice 4 PARITY Move down to the PARAMETER level to select the parity Use the left right arrow keys to see the parity choices Choose from one of the following None 8 Bits Odd 7 Bits or Even 7 bits When you set parity you are indirectly setting the number of data bits NONE 8 BITS Save the change and turn off the menu The parity selection is stored in non volatile memory and does not change when power has been off or after a remote interface reset N 20 Chapter 4 Remote Interface Reference SCPI Conformance Information
87. IN to set the frequency to its minimum value or MAX to set the frequency to its maximum value 218 Chapter 4 Remote Interface Reference An Introduction to the SCPI Language Querying Parameter Settings You can query the current value of most parameters by adding a question mark to the command For example the following command sets the output frequency to 5 kHz FREQ 5000 You can query the frequency value by executing n FREQ You can also query the minimum or maximum frequency allowed with the present function as follows FREQ MIN FREQ MAX SCPI Command Terminators A command string sent to the function generator must terminate with a neu line character The IEEE 488 EOI end or identify message is interpreted as a lt new line gt character and can be used to terminate a command string in place of a lt new line gt character A lt carriage return gt followed by a lt new line gt is also accepted Command string termination will always reset the current SCPI command path to the root level IEEE 488 2 Common Commands The IEEE 488 2 standard defines a set of common commands that perform functions like reset self test and status operations Common commands always begin with an asterisk are four to five characters in length and may include one or more parameters The command keyword is separated from the first parameter by a blank space Use a semicolon to separate multiple commands
88. INTERRUPTED A command was received which sends data to the output buffer but the output buffer contained data from a previous command the previous data is not overwritten The output buffer is cleared when power has been off or after a device clear has been executed Query UNTERMINATED The function generator was addressed to talk i e to send data over the interface but a command has not been received which sends data to the output buffer For example you may have executed an APPLy command which does not generate data and then attempted an ENTER statement to read data from the remote interface Query DEADLOCKED A command was received which generates too much data to fit in the output buffer and the input buffer is also full Command execution continues but all data is lost Query UNTERMINATED after indefinite response The IDN command must be the last query command within a command string Example IDN SYST VERS 235 501 502 511 512 513 514 521 522 550 580 800 810 Chapter 5 Error Messages Execution Errors Isolator UART framing error Isolator UART overrun error RS 232 framing error RS 232 overrun error RS 232 parity error Command allowed only with RS 232 The following three commands are used only with RS 232 SYSTem LOCal SYSTem REMote and SYSTem RWLock Input buffer overflow Output buffer overflow Command not allowed in local You should always exe
89. Interface Commands 200 The SCPI Status Registers 201 Status Reporting Commands 209 An Introduction to the SCPI Language 211 Halting an Output in Progress 216 To set the GPIB address 217 To select the remote interface 218 To set the baud rate 219 To set the parity 220 SCPI Conformance Information 221 IEEE 488 Conformance Information 225 Chapter 5 Error Messages Execution Errors 229 Self Test Errors 237 Calibration Errors 238 Arbitrary Waveform Errors 240 10 Contents Chapter 6 Application Programs BASIC Programs 244 C Language Programs 244 QuickBASIC Language Programs 247 Using the APPLy Command 248 Using the Low Level Commands 252 Downloading an Arbitrary Waveform over GPIB 255 Using the Status Registers 261 Downloading an Arbitrary Waveform over RS 232 267 Chapter 7 Tutorial Direct Digital Synthesis 273 Signal Imperfections 276 Creating Arbitrary Waveforms 278 Output Amplitude Control 280 Floating Signal Generators 282 Attributes of AC Signals 283 Modulation 287 Chapter 8 Specifications Frequency Characteristics 298 Sinewave Spectral Purity 298 Signal Characteristics 298 Output Characteristics 298 Modulation Characteristics 299 Frequency Sweep 299 System Characteristics 299 General Specifications 300 Product Dimensions 301 Index 303 Declaration of Conformity 309 11 U9 U04 Contents 12 Quick Start Quick Start One of the first things you will want to d
90. LATILE Select one of the five built in arbitrary waveforms one of four user defined waveforms or the waveform currently downloaded to VOLATILE memory e The names of the five built in arbitrary waveforms are SINC NEG RAMP EXP RISE EXP FALL and CARDIAC e To select the waveform currently stored in volatile memory specify the VOLATILE parameter The keyword VOLATILE does not havea short form The correct syntax is FUNC USER VOLATILE e The FUNC USER command does not output the selected waveform Use the FUNC SHAP USER command to output the waveform e Ifyou select an arbitrary waveform name that is not currently downloaded a 785 Specified arb waveform does not exist error is generated e The arb name may contain up to 8 characters The first character must be a letter A Z but the remaining characters can be numbers 0 9 or the underscore character _ Blank spaces are not allowed If you specify a name with more than 8 characters a 783 Arb waveform name too long error is generated e The function generator does not distinguish between upper and lower case letters for the arbitrary waveform name Therefore ARB 1 and arb 1 are the same name All characters are converted to upper case e Use the DATA CAT command to list the names of the five built in waveforms non volatile VOLATILE if a waveform is currently downloaded to volatile memory and th
91. LSB of each data point is sent first Most PCs use the swapped byte order 180 Chapter 4 Remote Interface Reference Arbitrary Waveform Commands DATA ATTRibute AVERage lt arb name gt Query the arithmetic average of all data points for the specified arbitrary waveform The default arb name is the arbitrary waveform currently active selected with FUNC USER command e Ifyou query a waveform that is not currently stored in memory a 785 Specified arb waveform does not exist error is generated DATA ATTRibute CFACtor lt arb name gt Query the crest factor of all data points for the specified arbitrary waveform Crest factor is the ratio of the peak value to the RMS value of the waveform The default arb name is the arbitrary waveform currently active selected with FUNC USER command e Ifyou query a waveform that is not currently stored in memory a 785 Specified arb waveform does not exist error is generated DATA ATTRibute POINts lt arb name gt Query the number of points in the specified arbitrary waveform Returns a value between 8 and 16 000 points The default arb name is the arbitrary waveform currently active selected with FUNC USER command e Ifyou query a waveform that is not currently stored in memory a 785 Specified arb waveform does not exist error is generated DATA ATTRibute PTPeak lt arb name gt Query the peak to peak value of all data p
92. M SOUR BM NCYC BM INT RATE BM PHAS External Triggered Mode External Internal Available Not Used Available Internal Triggered Mode Internal Internal Available Available Available External Gated Mode Internal External Not Used Not Used Not Used 81 Chapter 3 Features and Functions Burst Modulation Burst Trigger Source In wi the triggered burst mode the function generator outputs a waveform th the specified number of cycles burst count each time a trigger is received After the specified number of cycles has been output the function generator waits for the next trigger while outputting no signal zero volts or the dc offset level At power on the internally triggered bu rst mode is enabled Trigger source Internal Single or External The default is Internal In the triggered burst mode the burst source is Internal When the internal trigger source is selected the frequency at which the burst is generated is determined by the burst rate parameter The burst rate frequency defines the interval between bursts Pressing Single to enable the single trigger mode also enables the external trigger mode External triggering is like the front panel single trigger mode except that you apply a trigger signal to the rear panel Ext Trig terminal The function generator is triggered on the rising edge of a TTL pulse The Trig annunciator turns on when the function generator is waiting for a single
93. MAXimum 92 Chapter 3 Features and Functions Frequency Shift Keying FSK Modulation FSK Rate The FSK rate is the rate at which the output frequency shifts between the carrier frequency and the hop frequency when you select the internal FSK source FSK rate internal source 10 mHz to 50 kHz The default is 10 Hz The FSK rate is ignored when the external source is selected Front Panel Operation 9 FSK RATE MOD MENU Remote Interface Operation FSKey INTernal RATE lt rate in Hz gt MINimum MAXimum FSK Source FSK source Internal or External The default is Internal When the internal source is selected the rate at which the output frequency shifts between the carrier frequency and hop frequency is determined by the FSK rate specified When the external source is selected the output frequency is determined by the signal level on the rear panel FSK terminal When a low TTL level is present the carrier frequency is output When a high TTL level is present the hop frequency is output The maximum external FSK rate is 1 MHz The Ext annunciator turns on when the function generator is waiting for an external trigger signal Front Panel Operation 10 FSK SRC MOD MENU Remote Interface Operation FSKey SOURce INTernal EXTernal 93 Chapter 3 Features and Functions Frequency Sweep Frequency Sweep In the frequency sweep mode the function generator
94. MENU If the ERROR annunciator is on press Shitt Recall Menu to read the errors stored in the queue The errors are listed horizontally on the PARAMETER level All errors are cleared when you go to the PARAMETER level and then turn off the menu First error in queue c Error code e Remote Interface Operation SYSTem ERRor Reads one error from the error queue Errors have the following format the error string may contain up to 80 characters 113 Undefined header 228 101 102 103 105 108 109 112 Chapter 5 Error Messages Execution Errors Execution Errors Invalid character An invalid character was found in the command string You may have inserted a character such as or in the command header or within a parameter Example TRIG SOUR BUS Syntax error Invalid syntax was found in the command string You may have inserted a blank space before or after a colon or before a comma in the command header Example APPL SIN Pal Invalid separator An invalid separator was found in the command string You may have used a comma instead of a colon semicolon or blank space or you may have used a blank space instead of acomma Example TRIG SOUR BUS or APPL SIN 1 1000 GET not allowed A Group Execute Trigger GET is not allowed within a command string Parameter not allowed More parameters were rece
95. OFF or 0 For a true condition the function generator will accept ON or 1 When you query a boolean setting the instrument will always return 0 or 1 The following command uses a boolean parameter AM STATe OFF ON String Parameters String parameters can contain virtually any set of ASCII characters A string must begin and end with matching quotes either with a single quote or with a double quote You can include the quote delimiter as part of the string by typing it twice without any characters in between The following command uses a string parameter DISPlay TEXT lt quoted string 215 Chapter 4 Remote Interface Reference Halting an Output in Progress Halting an Output in Progress You can send a device clear at any time to stop an output in progress over the GPIB interface The status registers the error queue and all configuration states are left unchanged when a device clear message is received Device clear performs the following actions e The function generator s input and output buffers are cleared e The function generator is prepared to accept a new command string e The following statement shows how to send a device clear over the GPIB interface CLEAR 710 IEEE 488 Device Clear e The following statement shows how to send a device clear over the GPIB interface using the GPIB Command Library for C or QuickBASIC IOCLEAR 710 For RS 232 operation
96. SCPI Conformance Information The Agilent 33120A Function Generator Arbitrary Waveform Generator conforms to the 1993 0 version of the SCPI standard Many of the commands required by the standard are accepted by the function generator but are not described in this manual for simplicity or clarity Most of these non documented commands duplicate the functionality of a command already described in this manual SCPI Confirmed Commands The following table lists the SCPI approved commands that are used by the function generator SCPI Confirmed Commands CALibration ALL VALue lt value gt VALue DATA CATalog COPY lt destination arb name gt VOLATILI DATA VOLATILE lt value gt lt value gt Gl ra DELetes ALL DELete NAME arb name gt DISPlay WINDow STATe OFF ON WINDow STATe WINDow TEXT CLEar WINDow TEXT DATA lt quoted string gt WINDow TEXT DATA FORMat BORDer NORMal SWAPped BORDer SOURce AM DEPTh depth in percent MINimum MAXimum AM DEPTh MINimum MAXimum AM INTernal FREQuency frequency MINimum MAXimum AM INTernal FREQuency MINimum MAXimum AM SOURce EXTernal AM SOURCe 221 Chapter 4 Remote Interface Reference SCPI Conformance Information SCPI Confirmed Commands continued SOURce SYSTem AM STATe OFF ON AM
97. STATe FM DEViation peak deviation in Hz MINimum MAXimum FM DEViation MINimum MAXimum FM INTernal FREQuency frequency MINimum MAXimum FM INTernal FREQuency MINimum MAXimum FM STATe OFF ON FM STATe EQuency EQuency EQuency vu Hj Hj j tj j j tj j nj tj j C MODE S EQuency EQuency EQuency EQuency UNCtion SHAPe SINusoid SQUare TRIangle RAMP NOISe DC US UNCtion SHAPe ULSe DCYCle percent MINimum MAXimum ULSe DCYCle MINimum MAXimum R R R R REQuency R R R R lt frequency gt MINimum MAXimum EQuency MINimum MAXimum ENTer PAN STARt frequency MINimum MAXimum STARt MINimum MAXimum STOP frequency MINimum MAXimum STOP MINimum MAXimum Ii R SWEep SPACing LINear LOGarithmic SWEep SPACing SWEep TIME lt seconds gt MINimum MAXimum SWEep TIME MINimum MAXimum VOLTage LEVel IMMediate AMPLitude amplitude MINimum MAXimum VOLTage EVel IMMediate AMPLitude MINimum MAXimum VOLTage EVel IMMediate OFFSet offset MINimum MAXimum VOLTagel EVel IMMediate OFFSet MINimum MAXimum VOLTage UNIT VPP VRMS DBM DEFault VOLTage UNIT BEEPer IMMediate RRor ERSion lt TRIGger SEQuence SEQuence SOURce IMMediate EXTernal BUS SOURce 22
98. STATe Query the state of burst modulation Returns 0 OFF or 1 ON TRIGger SOURce IMMediate EXTernal BUS Select the burst trigger source In the triggered burst mode the function generator outputs a waveform with the specified number of cycles burst count each time a trigger is received After the specified number of cycles has been output the function generator waits for the next trigger while outputting no signal zero volts or the dc offset level The default is IMM Stored in volatile memory e In the triggered burst mode the burst source is Internal e When the Immediate internal trigger source is selected the frequency at which the burst is generated is determined by the burst rate BM INT RATE The APPLy command automatically sets the trigger source to IMMediate e When the External trigger source is selected the function generator will accept a hardware trigger applied to the rear panel Ext Trig terminal The function generator outputs the specified number of cycles each time Ext Trig receives the rising edge of a TTL pulse The Trig annunciator turns on when the function generator is waiting for an external trigger e When the Bus software source is selected the function generator outputs one burst each time a bus trigger command is received To trigger the function generator from the remote interface GPIB or RS 232 send the TRG trigger command You can
99. Software for Microsoft Windows is designed to make it easy to create and output arbitrary waveforms for the 33120A 272 Chapter 7 Tutorial Direct Digital Synthesis Direct Digital Synthesis Digital signal processing methods are used in many everyday applications Whether it is a digital audio compact disc player an electronic synthesized piano or a voice synthesized telephone message system it is obvious that complex waveforms can be easily created or reproduced using digital signal generation methods The 33120A uses a signal generation technique called direct digital synthesis or DDS The basic principle behind DDS is not unlike an audio compact disc As shown below for digital audio a stream of digital data representing the sampled analog signal shape is sequentially addressed from a disc This data is applied to the digital port of a digital to analog converter DAC which is clocked at a constant rate The digital data is then converted into a series of voltage steps approximating the original analog signal shape After filtering the voltage steps the original analog waveshape will be recovered The incoming data can be of any arbitrary shape as long as it matches the requirements of the particular DAC 16 bits for digital audio players l Anti Alias Filter Data COME PS D to A SS A io gt Converter 273 Direct Digital Synthesis continued Chapter 7 Tutorial Direct Digital Synthesis A d
100. URCE MOD MENU Remote Interface Operation AM SOURce BOTH EXTernal 75 Chapter 3 Features and Functions Frequency Modulation FM Frequency Modulation FM A modulated waveform consists of a carrier waveform and a modulating waveform In FM the frequency of the carrier is varied by the frequency of the modulating waveform The function generator will accept only an internal FM modulating signal no external source is available For more information on the fundamentals of Frequency Modulation refer to chapter 7 Tutorial To Select FM Modulation e The FM annunciator turns on when FM is enabled e Only one modulation mode can be enabled at a time When you enable FM the previous modulation mode is turned off e Front Panel Operation Enable FM before setting up the other modulation parameters Press Shift FM to output an FM waveform using the present settings for the carrier frequency modulating frequency output amplitude and offset voltage e Remote Interface Operation To ensure proper operation you should enable FM after you have set up the other modulation parameters FM STATe OFF ON 76 Chapter 3 Features and Functions Frequency Modulation FM Carrier Waveform Shape FM carrier shape Sine Square Triangle Ramp or Arbitrary waveform The default is Sine You cannot use the noise function or dc volts as the carrier waveform Front Panel Operation Press any
101. VOLATILE memory are not remembered However if an arbitrary waveform is being output from non volatile memory when the state is stored the waveform data is stored The stored waveform is output when the instrument state is recalled If you delete an arbitrary waveform after storing the state the waveform data is lost and the function generator will not output the waveform when the state is recalled The SINC waveform is output in place of the deleted waveform When power is turned off the function generator automatically stores its state in memory location 0 You can configure the function generator to automatically recall the power down state when power is restored The recall mode is disabled when the function generator is shipped from the factory Select the POWER ON LAST STATE command from the SYS MENU to enable the power down recall mode Select POWER ON DEFAULT to disable the power down recall mode See Power Down Recall Mode on page 109 for more information 191 Chapter 4 Remote Interface Reference System Related Commands RCL 0 1 2 3 Recall a previously stored state To recall a stored state you must use the same memory location used previously to store the state e You cannot recall the instrument state from a memory location that was not previously specified as a storage location For example an error is generated if you attempt to recall from memory location 2 but have never stored to
102. a rate determined by the internal rate generator or an external signal applied to the rear panel connector The function generator can produce a burst using sine square triangle ramp and arbitrary waveforms For more information on the fundamentals of Burst Modulation refer to chapter 7 Tutorial You can use burst modulation in the following two modes The function generator enables one burst mode at a time based on the trigger source and burst source that you select see the table below e Triggered Burst Mode In this mode the function generator outputs a waveform with a specified number of cycles burst count each time a trigger is received After the specified number of cycles has been output the function generator waits for the next trigger You can configure the function generator to accept an internal trigger or you can send the trigger externally by pressing the front panel Single key or by applying a trigger signal to the rear panel Ext Trig terminal At power on the internally triggered burst mode is enabled External Gated Burst Mode In this mode the output waveform is either on or off based on the level of the external signal applied to the rear panel Ext Trig terminal When the gate signal is true the function generator outputs a continuous waveform When the gate signal is false the output is turned off Trigger Source Burst Source Burst Count Burst Rate Burst Phase TRIG SOUR B
103. al wiring may not be correct The 34398A Cable Kit can be used to connect the function generator to most computers or terminals e Verify that you have connected the interface cable to the correct serial port on your computer COM1 COM2 etc 199 Chapter 4 Remote Interface Reference RS 232 Interface Commands RS 232 Interface Commands Use the front panel I O MENU to select the baud rate parity and number of data bits see pages 219 and 220 for more information SYSTem LOCal Place the function generator in the local mode for RS 232 operation All keys on the front panel are fully functional SYSTem REMote Place the function generator in the remote mode for RS 232 operation All keys on the front panel except the LOCAL key are disabled It is very important that you send the SYSTEM REMOTE command to place the function generator in the remote mode Sending or receiving data over the RS 232 interface when not configured for remote operation can cause unpredictable results SYSTem RWLock Place the function generator in the remote mode for RS 232 operation This command is the same as the SYSTEM REMOTE command except that all keys on the front panel are disabled including the LOCAL key Ctrl C Clear the operation in progress over the RS 232 interface and discard any pending output data This is equivalent to the IEEE 488 device clear action over the GPIB interface 200 Chapter 4 Re
104. alue The following steps show you how to enter a number in the menu For this example you will set the number of cycles for the burst modulation mode Turn on the menu You enter the menu on the MENUS level The MOD MENU is your first choice on this level A MOD MENU Move down to the COMMANDS level within the MOD MENU The AM SHAPE command is your first choice on this level 1 AM SHAPE Move across to the BURST CNT command on this level There are ten command choices available in the MOD MENU BURST CNT i You can also use the knob to scroll left or right through the choices on each level of the menu 38 Enter Chapter 2 Front Panel Menu Operation A front panel menu tutorial 4 Move down a level to edit the BURST CNT parameter The number of cycles should be 1 when you come to this point in the menu for the first time For this example you will set the number of cycles to 4 Notice that the Burst annunciator flashes indicating that the displayed value is for the burst mode 00001 CYC When you see the flashing on the left side of the display you can press to abort the edit and return to the COMMANDS level 5 Move the flashing cursor over to edit the last digit Notice that the rightmost digit is flashing the digit wraps around 00001 CYC 6 Increment the last digit until 4 is displayed 91 You decrement
105. arbitrary waveforms does not apply to ramp and triangle waveforms the relationship between the carrier frequency and the minimum burst count is shown below Carrier Minimum Frequency Burst Count 10 mHz to 1 MHz gt 1 MHz to 2 MHz gt 2 MHz to 3 MHz gt 3 MHz to 4 MHz gt 4 MHz to 5 MHz For sine square and arbitrary waveforms only AUN If you attempt to set the carrier frequency to a value that is not valid the function generator will automatically adjust the frequency to the maximum value allowed with the present burst count From the remote interface a 221 Settings conflict error is generated and the carrier frequency is adjusted 162 Chapter 4 Remote Interface Reference Burst Modulation Commands e For all waveforms used with burst if the carrier frequency is set less than or equal to 100 Hz the following relationship applies Burst Count Carrier Frequency lt 500 seconds For Carrier lt 100 Hz If you attempt to set the carrier frequency to a value that is not valid the function generator will automatically adjust the frequency to the minimum value allowed with the present burst count From the remote interface a 221 Settings conflict error is generated and the frequency is adjusted BM NCYCles MINimum MAXimum Query the burst count Returns an integer between 1 and 50 000 BM PHASe degrees MINimum MAXimum Set the starting phase for the burst triggered b
106. as shown below RST CLS ESE 32 OPC 214 Chapter 4 Remote Interface Reference An Introduction to the SCPI Language SCPI Parameter Types The SCPI language defines several different data formats to be used in program messages and response messages Numeric Parameters Commands that require numeric parameters will accept all commonly used decimal representations of numbers including optional signs decimal points and scientific notation Special values for numeric parameters like MINimum MAXimum and DEFault are also accepted You can also send engineering unit suffixes with numeric parameters e g Mhz or Khz If only specific numeric values are accepted the function generator will automatically round the input numeric parameters The following command uses a numeric parameter FREQuency lt frequency gt MINimum MAXimum Discrete Parameters Discrete parameters are used to program settings that have a limited number of values like BUS IMMediate EXTernal They have a short form and a long form just like command keywords You can mix upper and lower case letters Query responses will always return the short form in all upper case letters The following command uses discrete parameters SWEep SPACing LINear LOGarithmic Boolean Parameters Boolean parameters represent a single binary condition that is either true or false For a false condition the function generator will accept
107. assis 6 Group Execute Trigger 101 186 H handle adjustment 18 changing positions 18 removing 27 handshake RS 232 198 haversine example 248 heartbeat waveform 175 hop frequency FSK 92 168 HP IB address See GPIB address I identification string 113 190 IEEE 488 common commands 214 225 conformance information 225 selecting interface 115 218 IEEE 488 address factory setting 114 217 selecting 114 217 inherent offset 63 177 interface address factory setting 114 217 selecting 114 217 IntuiLink software 1 305 Index interface remote selecting 115 218 triggering 101 186 internal burst rate 88 164 internal FSK rate 93 168 internal triggering 99 186 inventory checklist 15 IOTRIGGER command 101 L language interface query 117 190 SCPI introduction 211 215 line voltage fuse 16 selecting 16 linear spacing sweep 96 172 load output termination front panel selection 40 65 remote interface selection 65 151 schematic diagram 281 logarithmic spacing sweep 96 172 logic levels Ext Trig FSK Burst terminal 102 long form SCPI commands 212 low level commands 136 M manual overview 7 MEM STAT DEL command 153 memory available arbs 185 menu front panel examples 33 39 menu recall 33 37 messages 34 operation 29 overview 4 reference 31 32 message calibration 122 errors 227 241 front panel display 112 188 messag
108. ating waveform Used only when the internal modulation source is selected AM SOUR INT You can use the noise function as the modulating waveform However you cannot use the noise function or de volts as the carrier waveform The default is SIN Stored in volatile memory AM INTernal FUNCtion Query the shape of the internal modulating waveform Returns SIN SQU TRI R A MP NOIS or USER AM INTernal FREQuency lt frequency gt MINimum MAXimum Set the frequency of the modulating waveform Used only when the internal modulation source is selected AM SOUR INT Select from 10 mHz to 20 kHz The default is 100 Hz MIN 10 mHz MAX 20 kHz Stored in volatile memory AM INTernal FREQuency MINimum MAXimum Query the internal modulating frequency Returns a value in hertz 155 Chapter 4 Remote Interface Reference AM Modulation Commands AM SOURce BOTH EXTernal Select the source of the modulating signal The function generator will accept an internal modulating signal an external modulating signal or both The default is BOTH Stored in volatile memory e The External modulating source is always enabled e When both sources are enabled internal external the function generator adds the internal and external modulating signals the carrier waveform is actually modulated with two waveforms e When the internal source is disabled external only the carrier wave
109. aveform CLEAR 7 ASSIGN Fgen TO 710 COM Fgen INTEGER Hpib Mask Value B OUTPUT Fgen RST Set up error checking Hpib 7 ON INTR Hpib CALL Err msg Mask 2 ENABLE INTR Hpib Mask OUTPUT Fgen CLS OUTPUT Fgen SRE 32 OUTPUT Fgen ESE 60 Clear interface send device clear Assign I O path to address 710 Use same address in subprogram Declare integer variables Reset function generator GPIB select code is 7 Call subprogram if error occurs Bit 1 is SRQ Enable SRQ to interrupt program Clear status registers clear out old errors Enable Standard Event bit in Status Byte to pull the IEEE 488 SRQ line Enable error bits 2 3 4 or 5 to set Standard Event bit in Status Byte and wait for operation complete 261 250 260 270 280 290 300 310 320 330 340 350 360 370 380 390 400 410 420 430 440 450 460 470 480 490 500 510 520 530 540 550 560 570 Chapter 6 Application Programs Using the Status Registers continued Set up function generator to output FM waveform o El J UTPUT Fgen OUTP LOAD 50 UTPUT Fgen APPL SIN 5000 5 o j J UT Fgen FM INT FUNC SIN UT Fgen FM INT FREQ 500 UT Fgen FM DEV 250 UTPUT Fgen FM STAT ON U UU YU oooo OUTPUT Fgen OPC ENTER Fgen Value OFF INTR Hpib
110. ber mode to enter a number with the appropriate units MHz m Vpp kHz m Vrms Hz dBm Back Space E Use Enter for those operations that do not require units to be specified AM Level Offset Duty and Store Recall State The Front Panel Menu at a Glance The menu is organized in a top down tree structure with three levels To turn on menu press MENU r 3 uon To move To move Zi vj Up or down right or left A MOD MENU wm B SWP MENU C EDIT MENU wm D SYS MENU wmb E O MENU wmb F CAL MENU 4 4 4 4 4 4 1 AM SHAPE 2 aM SouRCE m 1 START F m 1N ARB tour TERM m tween m 1 SECURED m To enter command press Enter A MODulation MENU 1 AM SHAPE gt 2 AM SOURCE gt 3 FM SHAPE gt 4 BURST CNT gt 5 BURST RATE gt 6 BURST PHAS gt 7 BURST SRC gt 8 FSK FREQ gt 9 FSK RATE gt 10 FSK SRC B SWP Sweep MENU 1 START F gt 2 STOP F gt 3 SWP TIME gt 4 SWP MODE C EDIT MENU 1 NEW ARB gt 2 POINTS gt 3 LINE EDIT gt 4 POINT EDIT gt 5 INVERT gt 6 SAVE AS 9 7 DELETE The commands enclosed in square brackets are hidden until you make a selection from the NEW ARB command to initiate a new edit session D SYStem MENU 1 OUT TERM gt 2 POWER ON 3 ERROR 4 TEST gt 5 COMMA gt 6 REVISION E Inpu
111. ber mode to set the amplitude e Remote Interface Operation VOLTage amplitude MINimum MAXimum You can also use the APPLy command to select the function frequency amplitude and offset with a single command 61 Chapter 3 Features and Functions Output Configuration DC Offset Voltage At power on the dc offset is set to 0 volts You can set the offset to a positive or negative number with the restrictions shown below If the specified offset voltage is not valid the function generator will automatically adjust it to the maximum dc voltage allowed with the present amplitude Vmax is either 10 volts for a high impedance termination or 5 volts for a 50 ohm termination Vpp is the output amplitude in volts peak to peak V Voffset xe lt Vmax and Voffset lt 2x Vpp From the front panel MAX VALUE is displayed and the offset is adjusted From the remote interface a 221 Settings conflict error is generated and the offset is adjusted e DC Offset and Output Termination The offset voltage is automatically adjusted and no error is generated if you change the output termination For example if you set the offset to 100 mVdc and then change the termination from 50 ohms to high impedance the displayed offset will double to 200 mVdc If you change from high impedance to 50 ohms the displayed offset will drop in half See Output Termination on page 65 for more information e
112. ce Product maintenance agreements and other customer assistance agreements are available for Agilent Technologies products For assistance contact your nearest Agilent Technologies Sales and Service Office Further information is available on the Agilent web site at www agilent com find assist Trademark Information Microsoft and Windows are U S registered trademarks of Microsoft Corporation All other brand and product names are trademarks or registered trademarks of their respective companies Certification Agilent Technologies certifies that this product met its published specifi cations at the time of shipment from the factory Agilent Technologies further certifies that its calibration measurements are traceable to the United States National Institute of Standards and Technology to the extent allowed by that organization s calibration facility and to the calibra tion facilities of other International Standards Organization members Warranty The material contained in this document is provided as is and is subject to being changed with out notice in future editions Further to the maximum extent permitted by applicable law Agilent disclaims all warranties either express or implied with regard to this manual and any information contained herein including but not limited to the implied warranties of merchant ability and fitness for a particular purpose Agilent shall not be liable for errors
113. ce to IMMediate TRIGger SOURce IMMediate EXTernal BUS Internal Triggering In this trigger mode the function generator continuously outputs the burst or sweep as specified by the burst rate or sweep time This is the power on trigger source for both front panel and remote interface use To select the internal trigger source from the remote interface use the following command The APPLy command automatically sets the trigger source to IMMediate TRIGGER SOURCE IMMEDIATE 99 Chapter 3 Features and Functions Triggering Single Triggering In the single trigger mode front panel only you can manually trigger the function generator by pressing the front panel Single key The function generator outputs one burst or initiates one sweep each time you press the key The Trig annunciator turns on when the function generator is waiting for a single trigger The front panel Single key is disabled when in remote External Triggering In this trigger mode the function generator will accept a hardware trigger applied to the Ext Trig terminal The function generator outputs one burst or initiates one sweep each time Ext Trig receives the rising edge of a TTL pulse See also Ext Trig FSK Burst Input Terminal on page 102 e Front Panel Operation The external trigger mode is like the single trigger mode except that you apply the trigger to the Ext Trig terminal Pressing S
114. ckets indicate that the parameter is optional and can be omitted The brackets are not sent with the command string If you do not specify a value for an optional parameter the function generator chooses a default value 212 Chapter 4 Remote Interface Reference An Introduction to the SCPI Language Command Separators A colon is used to separate a command keyword from a lower level keyword You must insert a blank space to separate a parameter from a command keyword If a command requires more than one parameter you must separate adjacent parameters using a comma as shown below APPL SIN 5 KHZ 3 0 VPP 2 5 V A semicolon is used to separate commands within the same subsystem and can also minimize typing For example sending the following command string FREQ START 10 STOP 1000 MODE SWEEP is the same as sending the following three commands FREQ START 10 FREQ STOP 1000 FREQ MODE SWEEP Use a colon and a semicolon to link commands from different subsystems For example in the following command string an error is generated if you do not use both the colon and semicolon SWE STAT ON TRIG SOUR EXT Using the MIN and MAX Parameters You can substitute MINimum or MAXimum in place of a parameter for many commands For example consider the following command FREQuency frequency MINimum MAXimum Instead of selecting a specific frequency you can substitute M
115. computer or terminal has a 9 pin serial port with a male connector use the null modem cable included with the 34398A Cable Kit This cable has a 9 pin female connector on each end The cable pin diagram is shown below DB 25 Serial Connection If your computer or terminal has a 25 pin serial port with a male connector use the null modem cable and 25 pin adapter included with the 34398A Cable Kit The cable and adapter pin diagram is shown below ee Ne UNUS cm nstrument PC Printer DCD 1 1 1 So ts X 2 2 2 E TX 3 3 3 z 4 0 4 4 Z 5 gt lt 5 5 Be t3 6 Ci ic 7 f 7 7 C 8 8 oo ER i l DB9 i 325 2 le Female Female e Female lale 197 In Chapter 4 Remote Interface Reference RS 232 Interface Configuration DTR DSR Handshake Protocol The function generator is configured as a DTE Data Terminal Equipment device and uses the DTR Data Terminal Ready and DSR Data Set Ready lines of the RS 232 interface to handshake The function generator uses the DTR line to send a hold off signal The DTR line must be TRUE before the function generator will accept data from the interface When the function generator sets the DTR line FALSE the data must cease within 10 characters To disable the DTR DSR handshake do not connect the DTR line and tie the DSR line to logic TRUE If y
116. controlled using either triggered or externally gated methods When configured for triggered operation the function generator can output a carrier waveform with a user specified number of complete cycles Each time a trigger is received the specified number of complete cycles is output You can also specify a starting waveform phase in triggered operation Zero degrees is defined as the first data point in waveform memory The function generator will output the start phase as a dc output level while waiting for the next trigger Output dc offset voltages are not affected by burst modulation they are independently produced and summed into the function generator s output amplifier A three cycle bursted sine wave with 100 Hz burst rate In gated burst mode operation the rear panel Burst terminal is used to directly and asynchronously turn off the waveform DAC output The burst count burst rate and burst phase settings have no effect in this mode When the burst signal is true TTL high the function generator outputs the carrier waveform continuously When the burst signal is false TTL low the waveform DAC is forced to a zero output level Like triggered burst operation the output dc offset voltage is not affected by the external burst gate signal 291 Chapter 7 Tutorial Modulation For triggered burst operation the function generator creates an internal modulation signal which is exactly s
117. cts the Nusoid SQUare TRIangle RAMP USER You can also use the APPLy command to select the function frequency amplitude and offset with a single command Carrier Frequency e Carrier frequency 100 uHz to 15 MHz 100 kHz for triangle and ramp The default is 1 kHz e For arbitrary waveforms the maximum carrier frequency depends on the number of points specified in the waveform The five built in arbitrary waveforms can be output at a maximum of 5 MHz Number of Arb Points 8 to 8 192 8k 8 193 to 12 287 12k 12 288 to 16 000 Minimum Frequency 100 uHz 100 uHz 100 uHz Maximum Frequency 5 MHz 2 5 MHz 200 kHz e Front Panel Operation Press the Freq key to select any valid frequency for the selected function the present amplitude and offset voltage are used e Remote Interface Operation FREQuency lt frequency gt MI Nimum MAXimum 72 Chapter 3 Features and Functions Amplitude Modulation AM Modulating Waveform Shape The function generator will accept an internal modulating signal an external modulating signal or both Modulating waveform shape internal source Sine Square Triangle Ramp Noise or Arbitrary waveform The default is Sine You can use the noise function as the modulating waveform However you cannot use the noise function or dc volts as the carrier waveform Front Panel Operation After enabling AM press Recall Menu to go
118. cute the SYSTem REMote command before sending other commands over the RS 232 interface This error is also generated if you attempt to execute the DISP TEXT command while in the local mode this command is allowed in remote only Phase locked loop is unlocked Option 001 Phase Lock Only The function generator has detected an unlock condition You must execute the PHAS UNL ERR STAT ON command to enable this error Block length must be even The function generator represents binary data for arbitrary waveforms as a 12 bit integers which is sent as two bytes DATA DAC VOLATILE command only An odd number of bytes is not accepted because the function generator would not know how to interpret the last single byte State has not been stored The memory location specified in the RCL command was not used in a previous SAV command You cannot recall the instrument state from a memory location that was not previously specified as a storage location 236 590 601 602 603 604 605 606 607 608 625 626 Chapter 5 Error Messages Self Test Errors Self Test Errors The following errors indicate failures that may occur during a self test Refer to the Service Guide for more information T O processor reset possible low power line voltage Front panel does not respond RAM read write failed Waveform RAM readback failed Modulation RAM readback failed Serial configurat
119. cy gt stop frequency Set the sweep time Use the SWE TIME command to set the number of seconds required to sweep from the start frequency to the stop frequency Select the sweep mode Use the SWE SPAC command to select linear or logarithmic spacing Select the sweep trigger source Use the TRIG SOUR command to select the source from which the sweep will be triggered Enable sweep modulation Use the SWE STAT ON command to enable the sweep mode 170 Chapter 4 Remote Interface Reference Frequency Sweep Commands Sweep Commands To sweep up in frequency set the start frequency lt stop frequency To sweep down in frequency set the start frequency gt stop frequency FREQuency STARt frequency MINimum MAXimum Set the start frequency Select from 10 mHz to 15 MHz 100 kHz for triangle and ramp The sweep is phase continuous over the full frequency range The default is 100 Hz MIN 10 mHz MAX 15 MHz Stored in volatile memory FREQuency STARt MINimum MAXimum Query the start frequency Returns a value in hertz FREQuency STOP lt requency gt MINimum MAXimum Set the stop frequency Select from 10 mHz to 15 MHz 100 kHz for triangle and ramp The sweep is phase continuous over the full frequency range The default is 1 kHz MIN 10 mHz MAX 15 MHz Stored in volatile memory FREQuency STOP MINimum MAXimum Query the stop frequency Returns a value in hert
120. d 56 Chapter 3 Features and Functions Output Configuration Output Frequency As shown below the output frequency range depends on the function currently selected The default frequency is 1 kHz for all functions Function Sine Square Triangle Ramp Built In Arbs 1 Minimum Frequency 100 uHz 100 uHz 100 uHz 100 uHz 100 uHz Maximum Frequency 15 MHz 15 MHz 100 kHz 100 kHz 5 MHz 1 There are five built in arbitrary waveforms stored in non volatile memory sinc negative ramp exponential rise exponential fall and cardiac For arbitrary waveforms that you create and download to memory the maximum frequency depends on the number of points specified in the waveform As shown below the maximum output frequency decreases as you specify more points in the waveform The five built in arbitrary waveforms can be output at a maximum of 5 MHz Number of Arb Points 8 to 8 192 8k 8 193 to 12 287 12k 12 288 to 16 000 Minimum Frequency 100 uHz 100 uHz 100 uHz Maximum Frequency 5 MHz 2 5 MHz 200 kHz 57 Output Frequency continued Chapter 3 Features and Functions Output Configuration e Possible Conflict with Function Change The output frequency is automatically adjusted if you select a function whose maximum frequency is less than that of the currently active function For example if you output a 1 MHz sine wave and then change the functi
121. d bursts are generated to any value between 10 mHz and 50 kHz using the BM INT RATE command Used only in the triggered burst mode with an internal trigger source Set the burst starting phase Set the starting phase of the burst to any value between 360 degrees and 360 degrees using the BM PHAS command Used only in the triggered burst mode internal or external source Select the trigger source or burst source e Ifyou are using the triggered burst mode select the trigger source using the TRIG SOUR command e Ifyou are using the external gated burst mode select the external gate source using the BM SOUR EXT command Enable burst modulation After you have set up the other modulation parameters use the BM STAT ON command to enable the burst mode 161 Chapter 4 Remote Interface Reference Burst Modulation Commands Burst Modulation Commands Use the APPLy command or the equivalent FUNC SHAP FREQ VOLT and VOLT OFFS commands to configure the carrier waveform Set the carrier frequency between 10 mHz and 5 MHz 100 kHz for triangle and ramp The default is 1 kHz BM NCYCles lt cycles gt INFinity MINimum MAXimum Set the number of cycles to be output per burst triggered burst mode only Select from 1 cycle to 50 000 cycles in 1 cycle increments The default is 1 cycle MIN 1 cycle MAX 50 000 cycles Stored in volatile memory e For sine square and
122. d or the OPC operation complete command to signal when the sweep is complete The OPC command returns 1 to the output buffer when the sweep is complete The OPC command sets the operation complete bit bit 0 in the Standard Event register when the burst is complete TRIGger SOURce Query the present trigger source Returns IMM EXT or BUS 173 In Chapter 4 Remote Interface Reference Arbitrary Waveform Commands Arbitrary Waveform Commands See also Arbitrary Waveforms starting on page 103 in chapter 3 Arbitrary Waveform Overview The following is an overview of the steps required to download and output an arbitrary waveform over the remote interface The commands used for arbitrary waveforms are listed on page 176 Refer to chapter 7 Tutorial for more information on the internal operation of downloading and outputting an arbitrary waveform Chapter 6 Application Programs contains several example programs which show the use of arbitrary waveforms You may find it useful to refer to the programs after reading the following section in this chapter Select the waveform frequency amplitude and offset Use the APPLy command or the equivalent FREQ VOLT and VOLT OFFS commands to select the frequency amplitude and offset of the arbitrary waveform Download the data points into volatile memory You can download between 8 and 16 000 points per waveform The wav
123. de is adjusted From the remote interface a 221 Settings conflict error is generated and the amplitude is adjusted A momentary glitch occurs in the output waveform at certain voltages due to output attenuator switching This positive going glitch occurs when the output voltage crosses the break point voltage either from a lower voltage or a higher voltage The voltages are shown below for a 0 volt dc offset 252 mVpp 399 mVpp 502 mVpp 796 mVpp 1 Vpp 1 59 Vpp 2 0 Vpp 3 17 Vpp 3 99 Vpp 6 32 Vpp 7 96 Vpp The output voltage will momentarily drop to 0 volts at certain voltages due to output relay switching This occurs when the output voltage crosses the break point voltage either from a lower voltage or a higher voltage The voltages are shown below for a 0 volt dc offset 60 Chapter 3 Features and Functions Output Configuration e You can set the units for output amplitude to Vpp Vrms or dBm See Output Units on page 64 for more information e For dc volts the output level is actually controlled by setting the offset voltage You can set the dc voltage to any value between 5 Vdc into 50 ohms or 10 Vdc into an open circuit See DC Offset Voltage on page 62 for more information To select de volts from the front panel press Otfset and hold it down for more than 2 seconds e Front Panel Operation To set the output amplitude press Ampl Then use the knob arrow keys or Enter Num
124. displayed value between and a5 To cancel the number mode press Set the units to the desired value At this point the function generator outputs the waveform with the displayed offset Notice that the Offset annunciator turns on indicating that the waveform is being output with an offset The annunciator will turn on when the offset is any value other than 0 volts To turn off the flashing digit move the cursor to the left of the display using the arrow keys 01 50 mVDC You can also use the knob and arrow keys to enter a number See Front Panel Number Entry on page 3 for more information 21 Shift Duty Enter Number 4 5 Enter en 2 3 HG Chapter 1 Quick Start To set the duty cycle To set the duty cycle Applies only to square waves At power on the duty cycle for square waves is 50 You can adjust the duty cycle for a square waveform from 20 to 80 in increments of 1 for frequencies above 5 MHz the range is 40 to 60 The following steps show you how to change the duty cycle to 45 Select the square wave function Notice that the TL annunciator turns on indicating that the square wave function is enabled Enable the duty cycle modify mode The displayed duty cycle is either the power on value or the previous value selected 50 DUTY This message appears on the display for approximately 10 seconds Rep
125. ds to the binary weighted sum of all bits set in the register 209 Chapter 4 Remote Interface Reference Status Reporting Commands OPC Set the operation complete bit bit 0 in the Standard Event register after the previous commands have been executed Used only in the triggered burst mode and triggered sweep mode OPC Return 1 to the output buffer after the previous commands have been executed Used only in the triggered burst mode and triggered sweep mode PSC 0 1 Power on status clear Clear the Status Byte and Standard Event register enable masks when power is turned on PSC 1 When PSC 0 is in effect the Status Byte and Standard Event register enable masks are not cleared when power is turned on The factory setting is 1 enabled Stored in non volatile memory PSC Query the power on status clear setting Returns 0 PSC 0 or 1 PSC 1 SRE enable value Enable bits in the Status Byte enable register SRE Query the Status Byte enable register The function generator returns a decimal value which corresponds to the binary weighted sum of all bits set in the register STB Query the Status Byte summary register The STB command is similar to a serial poll but it is processed like any other instrument command The STB command returns the same result as a serial poll but the request service bit bit 6 is not cleared if a serial poll has occurred
126. dulation 100 modulation has a different meaning than in AM Modulation of 100 in FM indicates a variation of the carrier by the amount of the full permissible deviation Since the modulating signal only varies frequency the amplitude of the signal remains constant regardless of the modulation The function generator uses the deviation parameter to describe the peak frequency change above or below the carrier in response to a corresponding amplitude peak of the modulating signal For FM signals the bandwidth of the modulated signal can be approximated by BW 2 x Deviation Information Signal Bandwidth For wideband FM BW 2 x Information Signal Bandwidth For narrowband FM Narrowband FM occurs when the ratio of the deviation frequency to the information signal bandwidth is approximately 0 01 or less Wideband commercial FM radio stations in the United States use a 75 kHz peak deviation 150 kHz peak to peak and audio signals band limited to 15 kHz to achieve 200 kHz channel to channel spacing from the 180 kHz bandwidth 288 Chapter 7 Tutorial Modulation Frequency Sweep The 33120A performs phase continuous frequency sweeping stepping from the sweep start frequency to the sweep stop frequency with between 2 048 and 4 096 discrete frequency steps The direction of frequency sweeps can be varied by setting the stop frequency either above or below the start frequency Individual frequency steps are either linearly o
127. e e Remote Interface Operation PULSe DCYCle lt percent gt MINimum MAXimum The APPLy command automatically sets the duty cycle to 5096 for square waves 67 Chapter 3 Features and Functions Output Configuration SYNC Signal A sync signal output is provided on the front panel SYNC terminal All of the standard output functions except dc and noise have an associated sync signal For certain applications where you may not want to output the sync signal you can disable the SYNC terminal The SYNC terminal can be enabled disabled from the remote interface only e By default the sync signal is routed to the SYNC terminal enabled e When the sync signal is disabled the output level on the SYNC terminal is indeterminate it might be a TTL high or a TTL low e For sine square triangle and ramp waveforms the sync signal is a TTL high when the waveform s output is positive relative to zero volts or the dc offset value The signal is a TTL low when the output is negative relative to zero volts or the dc offset value e For arbitrary waveforms a momentary TTL high pulse gt 200 ns is output which corresponds to the first downloaded point in the waveform e For AM and FM the sync signal is referenced to the modulating signal not the carrier Amomentary TTL high pulse gt 200 ns is output at each zero crossing point of the modulating signal e For t
128. e F parameter 245 Chapter 6 Application Programs C Language Programs e To compile Borland Turbo C programs from the DOS command line using the large memory model execute the following tcc ml path program C gt path tchhpib 1lib gt For example tcc ml b Narb wave c c tc lib tchhpib lib Change the m1 parameter to the appropriate setting when compiling in the smaller memory models see your C Language manual for more information e Once compiled and linked an executable file EXE and object file OBJ are created in the current directory Run the program by typing the file name with the EXE extension 246 Chapter 6 Application Programs QuickBASIC Language Programs QuickBASIC Language Programs All of the QuickBASIC Language example programs in this chapter are written for the 82335 GPIB Interface Card using the GPIB Command Library for BASIC Running a QuickBASIC Program To run a program first compile and link the program to make an executable file You can either compile and link the program in the QuickBASIC environment or compile and link separately from the DOS command line e To compile and link a program in the QuickBASIC environment execute the following qb path program BAS gt 1 path Ngbhpib This loads both the program and the GPIB library into the QuickBASIC environment Note that this only selects the environment for QuickBASIC versi
129. e on page 219 e To set the parity on page 220 e SCPI Conformance Information starting on page 221 e IEEE 488 Conformance Information on page 225 For information on the programming commands for the Phase Lock Option refer to the User s and Service Guide included with Option 001 If you are a first time user of the SCPI language you may want to refer to these sections to become familiar with the language before attempting to program the function generator 126 First time SCPI users see page 211 Chapter 4 Remote Interface Reference SCPI Command Summary SCPI Command Summary This section summarizes the SCPI Standard Commands for Programmable Instruments commands available to program the function generator over the remote interface Refer to the later sections in this chapter for more complete details on each command Throughout this manual the following conventions are used for SCPI command syntax e Square brackets indicate optional keywords or parameters e Braces enclose parameters within a command string e Triangle brackets lt gt indicate that you must substitute a value for the enclosed parameter e A vertical bar separates multiple parameter choices The APPLy Commands see page 138 for more information APPLy SINusoid lt frequency gt lt amplitude gt lt offset gt APPLy SQUare lt frequency gt lt amplitude gt lt offset gt APPLy
130. e order lock link kit 5061 9694 and flange kit 5063 9212 To install one or two instruments in a sliding support shelf order shelf 5063 9255 and slide kit 1494 0015 for a single instrument also order filler panel 5002 3999 28 Front Panel Menu Operation Front Panel Menu Operation By now you should be familiar with some of the basic features of the front panel Chapter 1 shows you how to prepare the function generator for use and describes a few of the front panel features If you are not familiar with this information we recommend that you read chapter 1 Quick Start starting on page 13 Chapter 2 introduces you to the use of the front panel menu This chapter does not give a detailed description of every front panel key or menu operation It does however give you a good overview of the front panel menu and many front panel operations See chapter 3 Features and Functions starting on page 53 for a complete discussion of the function generator s capabilities and operation If you purchased the Phase Lock Option for the 33120A an additional menu G PHASE MENU is available from the front panel For information on using the Phase Lock Option refer to the User s and Service Guide included with Option 001 30 Chapter 2 Front Panel Menu Operation Front panel menu reference Front panel menu reference A MODulation MENU 1 AM SHAPE gt 2 AM SOURCE 3 FM SHAPE gt 4
131. e 65 for more information e Amomentary glitch occurs in the output waveform at certain voltages due to output attenuator switching This positive going glitch occurs when the output voltage crosses the break point voltage either from a lower voltage or a higher voltage The voltages are shown below for a 0 volt dc offset 252 mVpp 399 mVpp 502 mVpp 796 mVpp 1 Vpp 1 59 Vpp 2 0 Vpp 3 17 Vpp 3 99 Vpp 6 32 Vpp 7 96 Vpp e The output voltage will momentarily drop to 0 volts at certain voltages due to output relay switching This occurs when the output voltage crosses the break point voltage either from a lower voltage or a higher voltage The voltages are shown below for a 0 volt dc offset 141 Chapter 4 Remote Interface Reference Using the APPLy Command DC Offset Voltage e For the offset parameter of the APPLy command you can substitute MINimum MAXimum or DEFault in place of a specific value for the parameter MIN selects the smallest dc offset voltage for the selected function 0 volts MAX selects the largest offset for the selected function The default offset voltage is 0 volts for all functions e You can set the offset to a positive or negative number with the restrictions shown below If the specified offset voltage is not valid the function generator will automatically adjust it to the maximum dc voltage allowed with the present amplitude Vmax is the maximum peak to peak amplitude for the select
132. e Interface Reference Frequency Shift Keying FSK Commands Frequency Shift Keying FSK Commands See also FSK Modulation starting on page 90 in chapter 3 FSK Overview The following is an overview of the steps required to generate an FSK waveform The commands used for FSK are listed on the next page Set up the carrier waveform Use the APPLy command or the equivalent FUNC SHAP FREQ VOLT and VOLT OFFS commands to select the function frequency amplitude and offset of the carrier waveform You can select a sine square triangle ramp or arbitrary waveform for the carrier Select the FSK hop frequency Use the FSK FREQ command to set the hop frequency Set the FSK rate Use the FSK INT RATE command to set rate at which the output frequency shifts between the carrier frequency and the hop frequency internal FSK source only Select the FSK source Select an internal or external FSK source using the FSK SOUR command Enable FSK modulation After you have set up the other FSK parameters use the FSK STAT ON command to enable FSK modulation 167 Chapter 4 Remote Interface Reference Frequency Shift Keying FSK Commands FSK Commands Use the APPLy command or the equivalent FUNC SHAP FREQ VOLT and VOLT OFFS commands to configure the carrier waveform Set the carrier frequency between 10 mHz and 15 MHz 100 kHz for triangle and ramp The default is 1 kHz
133. e available 205 Microsoft Quick C8 244 MIN MAX parameters 143 213 modulating frequency AM 74 155 FM 79 159 FSK 92 168 modulating source AM 75 156 modulating waveshape AM 73 155 FM 79 159 modulation depth AM 74 155 with external source 75 155 N negative ramp waveform 175 new line character 214 Num annunciator 5 Number Entry mode 3 38 number of cycles burst 87 162 Nyquist Sampling Theorem 276 Oo odd parity 116 220 Offset annunciator 5 offset and arb waveforms 63 177 and dc voltage function 62 150 and output termination 62 150 front panel selection 21 remote interface selection 149 Option 001 Phase Lock See Option 001 User s Service Guide optional parameters APPLy 143 OUTP LOAD command 151 OUTP SYNC command 151 output amplitude and output termination 60 149 arb waveform limits 148 177 conflict with function 59 149 front panel selection 20 limits 59 148 remote interface selection 148 restrictions with offset 60 149 selecting units 64 150 output configuration 145 153 output frequency arb waveform limits 57 146 conflict with duty cycle 58 147 conflict with function 58 146 front panel selection 19 limits 57 146 modulation 76 157 remote interface selection 57 146 output function conflict with amplitude 55 conflict with frequency 55 front panel selection 56 modulation matrix 56 145 remote interface
134. e binary range of values corresponds to the values available using internal 12 bit DAC Digital to Analog Converter codes e The values 2047 and 2047 correspond to the peak values of the waveform For example if you have set the output amplitude to 10 Vpp 2047 corresponds to 5 volts and 2047 corresponds to 5 volts e The maximum amplitude will be limited if the data points do not span the full range of the output DAC Digital to Analog Converter For example the built in SINC waveform does not use the full range of values between 1 and therefore its maximum amplitude is 6 084 Vpp into 50 ohms e The DATA DAC VOLATILE command overwrites the previous waveform in VOLATILE memory no error is generated Use the DATA COPY command to copy the waveform to non volatile memory e Up to four user defined waveforms can be stored in non volatile memory Use the DATA DEL command to delete the waveform in VOLATILE memory or any of the four user defined waveforms in non volatile memory Use the DATA CAT command to list all waveforms currently stored in volatile and non volatile memory and the built in waveforms e After downloading the waveform data to memory use the FUNC USER command to choose the active waveform and the FUNC SHAP USER command to output it 179 DATA DAC VOLATILE continued Chapter 4 Remote Interface Reference Arbitrary Waveform Commands To download binar
135. e carrier and hop frequencies are set and output Now we will go back into the menu to set the FSK shift rate this is the rate at which the function generator shifts between the carrier frequency and hop frequency Use the menu to set the FSK shift rate The recall menu key returns you to the FSK FREQ command which was the last command used before you exited the menu 45 Chapter 2 Front Panel Menu Operation To output an FSK waveform gt 7 Move across to the FSK RATE command 9 FSK RATE v 8 Move down a level and set the FSK shift rate to 100 Hz Notice that the FSK annunciator flashes indicating that the displayed parameter is for the FSK mode For more information on editing numbers in the menu refer to Menu Example 3 earlier in this chapter 100 0 Hz Enter 9 Save the change and turn off the menu The function generator beeps and displays a message to show that the change is now in effect You are then exited from the menu ENTERED At this point the function generator outputs the FSK waveform You can also use an external signal to shift between the carrier frequency and hop frequency For more information see Frequency Shift Keying FSK Modulation in chapter 3 Chapter 2 Front Panel Menu Operation To output a burst waveform To output a burst waveform You can configure the function generator to output a waveform with a specified
136. e command Check to see if you have sent the correct data type with the command Expression errors The function generator does not accept mathematical expressions Trigger ignored A Group Execute Trigger GET or TRG was received but the trigger was ignored Make sure that you have selected the correct trigger source 231 221 221 221 221 Chapter 5 Error Messages Execution Errors Settings conflict amplitude has been adjusted The requested output amplitude is not valid The output amplitude is automatically adjusted to be compatible with the present configuration This error will be generated in the following instances e The output amplitude is automatically adjusted if you select a function whose maximum amplitude is less than that of the currently active function This conflict may arise when the output units are Vrms or dBm due to the differences in crest factor e Ifthe specified amplitude is not valid the function generator will automatically adjust it to the maximum value allowed with the present offset voltage The output amplitude in Vpp and the dc offset voltage must obey the following restrictions Vmax is either 10 volts for a high impedance termination or 5 volts for a 50 ohm termination V Voffset S X Vmax and Voffset lt 2x Vpp Settings conflict cannot adjust phase in present configuration Option 001 Phase Lock Only The phase cannot be adjusted real time if an arbitrary wavef
137. e made on the PARAMETER level is saved This is displayed after you press Enter Menu Enter to execute the command MIN VALUE The value you specified on the PARAMETER level is too small for the selected command The minimum value allowed is displayed for you to edit MAX VALUE The value you specified on the PARAMETER level is too large for the selected command The maximum value allowed is displayed for you to edit EXITING You will see this message if you turn off the menu by pressing Shift Menu On Off or Shift Cancel You did not edit any values on the PARAMETER level and changes were NOT saved NOT ENTERED You will see this message if you turn off the menu by pressing Shift Menu On Off or Shift Cancel You did some editing of parameters but the changes were NOT saved Press the Enter key Menu Enter to save changes made on the PARAMETER level 34 Menu Example 1 Shift Menu On Off Chapter 2 Front Panel Menu Operation A front panel menu tutorial The following steps show you how to turn on the menu move up and down between levels move across the choices on each level and turn off the menu In this example you will enable the function generator to automatically recall the power down state when power is turned on Turn on the menu You enter the menu on the MENUS level The MOD MENU is your first
138. e names of any user defined waveforms non volatile e The following statement shows how to use the FUNC USER command FUNC USER NEG_RAMP FUNCtion USER Query the arbitrary waveform currently selected Returns SINC NEG_RAMP EXP_RISE EXP_FALL CARDIAC VOLATILE or the name of any user defined waveforms in non volatile memory 176 Chapter 4 Remote Interface Reference Arbitrary Waveform Commands FUNCtion SHAPe USER Select the function and output the selected arbitrary waveform When executed this command outputs the arbitrary waveform currently selected by the FUNC USER command The selected waveform is output using the previously selected frequency amplitude and offset settings Use the FREQ VOLT and VOLT OFFS commands to select the frequency amplitude and offset of the waveform Or use the APPLy command to select the function frequency amplitude and offset with a single command As shown in the following table you can use the arbitrary waveform function with all of the modulation modes Each X indicates a valid combination Sine Square Triangle Ramp Noise Arb AM Carrier X X X X X AM Modulating Wave X X X X X X FM Carrier X X X X X FM Modulating Wave X X X X X X FSK Modulation X X X X X Burst Modulation X X X X X Frequency Sweep X X X X X For arbitrary waveforms the maximum amplitude will be limited if the data points do not s
139. e wave the function generator will adjust the output amplitude to 3 535 Vrms the upper limit for sine waves in Vrms From the front panel AMPL LIMIT is displayed and the amplitude is adjusted From the remote interface a 221 Settings conflict error is generated and the amplitude is adjusted 55 Chapter 3 Features and Functions Output Configuration Output Function e The following matrix shows which output functions are allowed with continued each modulation mode Each X indicates a valid combination If you change to a function that is not allowed with the selected modulation the modulation mode is turned off Sine Square Triangle Ramp Noise Arb AM Carrier X X X X X AM Modulating Wave X X X X X X FM Carrier X X X X X FM Modulating Wave X X X X X X FSK Modulation X X X X X Burst Modulation X X X X X Frequency Sweep X X X X X e Front Panel Operation To select a function press any key in the top row of function keys Press Arb to output the arbitrary waveform currently selected to scroll through the waveform choices and make a selection press Arb List e To select de volts from the front panel press Offset and hold it down for more than 2 seconds e Remote Interface Operation FUNCtion SHAPe SINusoid SQUare TRIangle RAMP NOISe USER DC You can also use the APPLy command to select the function frequency amplitude and offset with a single comman
140. eat this step as needed Enter the desired duty cycle Q Notice that the Num annunciator turns on and ENTER NUM flashes on the display indicating that the number mode is enabled 45 To cancel the number mode press Shift Cancel Output the waveform with the displayed duty cycle 45 DUTY You can also use the knob and arrow keys to enter a number See Front Panel Number Entry on page 3 for more information 22 Shift Arb List Enter 1 mn Chapter 1 Quick Start To output a stored arbitrary waveform To output a stored arbitrary waveform There are five built in arbitrary waveforms stored in non volatile memory for your use You can output these waveforms directly from non volatile memory The following steps show you how to output an exponential rise waveform from memory Display the list of arbitrary waveforms The list contains the five built in arbitrary waveforms sinc negative ramp exponential rise exponential fall and cardiac The list may also contain up to four user defined arbitrary waveform names The first choice on this level is SINC SINC EJA p This message appears on the display for approximately 10 seconds Repeat this step as needed Move across to the EXP RISE choice 91 EXP RISE Select and output the displayed arbitrary waveform Notice that the Arb annunciator turns on indicating that the o
141. eating arbitrary waveforms the function generator will always attempt to replicate the finite length time record to produce a periodic version of the data in waveform memory As shown on the next page it is possible that the shape and phase of a signal may be such that a transient is introduced at the end point When the waveshape is repeated for all time this end point transient will introduce leakage error in the frequency domain because many spectral terms are required to describe the discontinuity 278 Chapter 7 Tutorial Creating Arbitrary Waveforms Leakage error is caused when the waveform record does not include an integer number of cycles of the fundamental frequency Power from the fundamental frequency and its harmonics is transferred to spectral components of the rectangular sampling function Instead of the expected narrow spectral lines leakage can cause significant spreading around the desired spectral peaks You can reduce leakage errors by adjusting the window length to include an integer number of cycles or by including more cycles within the window to reduce the residual end point transient size Some signals are composed of discrete non harmonically related frequencies Since these signals are non repetitive all frequency components cannot be harmonically related to the window length You should be careful in these situations to minimize end point discontinuities and spectral leakage 0 90 180 270 360 0
142. ed output termination Vpp is the output amplitude in volts peak to peak From the remote interface a 221 Settings conflict error is generated and the offset is adjusted V Voffset E X Mmax and Voffset lt 2x Vpp e DC Offset and Output Termination The offset voltage is auto matically adjusted and no error is generated if you change the output termination For example if you set the offset to 100 mVdc and then change the termination from 50 ohms to high impedance the displayed offset will double to 200 mVdc If you change from high impedance to 50 ohms the displayed offset will drop in half See Output Termination on page 65 for more information e For arbitrary waveforms the Offset annunciator will turn on if the waveform data has an inherent offset present if the average is not equal to zero The function generator calculates the average of the data points and compares the average to zero volts If the average is not within two DAC Digital to Analog Converter counts of zero volts the Offset annunciator turns on e For dc volts the output level is actually controlled by setting the offset voltage You can set the dc voltage to any value between 5 Vdc into 50 ohms or 10 Vdc into an open circuit 142 Chapter 4 Remote Interface Reference Using the APPLy Command APPLy Command Syntax e Because of the use of optional parameters in the APPLy commands enclosed in square brackets you must
143. eform can be downloaded as floating point values or binary integer values Use the DATA VOLATILE command to download floating point values between 1 and 1 Use the DATA DAC VOLATILE command to download binary integer values between 2047 and 2047 To ensure that binary data is downloaded properly you must select the order in which the bytes are downloaded using the FORM BORD command 174 Chapter 4 Remote Interface Reference Arbitrary Waveform Commands Copy the arbitrary waveform to non volatile memory You can output the arbitrary waveform directly from volatile memory as described in step 2 or you can copy the waveform to non volatile memory Use the DATA COPY command to copy the waveform to non volatile memory Select the arbitrary waveform to output You can select one of the five built in arbitrary waveforms one of four user defined waveforms or the waveform currently downloaded to volatile memory Use the FUNC USER command to select the waveform Output the currently selected arbitrary waveform Use the FUNC SHAP USER command to output the waveform previously selected with the FUNC USER command The five built in arbitrary waveforms are shown below Sinc Negative Ramp Cardiac Exponential Rise Exponential Fall 175 Chapter 4 Remote Interface Reference Arbitrary Waveform Commands Arbitrary Waveform Commands FUNCtion USER arb name gt VO
144. eived over the GPIB interface static char cmd_string OUTP LOAD 50 Output termination is 50 ohms APPL SIN 5000 5 Carrier is a 5 kHz sine wave 5 Vpp BMINCYC 1 Burst count is 1 cycle BM PHAS 270 Starting phase is 270 degrees VOLT OFFS 2 5 Offset voltage is 2 5 Vdc TRIG SOUR BUS Trigger source is bus BM STAT ON Turn burst modulation on Ju Call the function to execute the command strings shown above command exe cmd string sizeof cmd string sizeof char Call the function to check for errors check error out waveform RRR RR KR RKK KE KKK RK KKK KKK KKK KKK KKK KK KKK KR KK KKK KKK KKK KKK KKK KKK KKK KKK KKK ckckckck ck k void command_exe char commands int length Execute one command string at a time using a loop int loop for loop 0 loop lt length loop IOOUTPUTS ADDR commands loop strlen commands loop RR RK KKK A RR RR KR A ck ck ck ck ck RR KR RK KKK KK ko ke KK J 250 Chapter 6 Application Programs Using the APPLy Command continued void check_error char func_name Read error queue to determine if errors have occurred char message 80 int length 80 IOOUTPUTS ADDR SYST ERR 9 Read the error queue IOENTERS ADDR message amp length Enter error string while atoi message 0 Loop until al
145. elect a function whose maximum frequency is less than that of the currently active function For example if you output a 1 MHz sine wave and then change the function to triangle wave the function generator will adjust the output to 100 kHz the upper limit for triangle waves Settings conflict fsk frequency has been adjusted The requested FSK hop frequency is not valid The FSK frequency is automatically adjusted if you select a function whose maximum frequency is less than that of the currently active function For example if you set the FSK frequency to 1 MHz in the sine function and then change the function to triangle wave the function generator will adjust the frequency to 100 kHz the upper limit for triangle waves Settings conflict offset has been adjusted The requested offset voltage is not valid with the present output amplitude The offset is automatically adjusted to the maximum value allowed with the present output amplitude The output amplitude in Vpp and the dc offset voltage must obey the following restrictions Vmax is either 10 volts for a high impedance termination or 5 volts for a 50 ohm termination V Voffset coe lt Vmax and Voffset lt 2x Vpp Settings conflict start frequency has been adjusted The requested start frequency is not valid The start frequency is automatically adjusted if you select a function whose maximum frequency is less than that of the currently active function Fo
146. emote interface For RS 232 operation make sure the interface is in the remote mode by sending the SYST REM command 187 Chapter 4 Remote Interface Reference System Related Commands System Related Commands See also System Related Operations starting on page 109 in chapter 3 DISPlay OFF ON Turn the front panel display off or on When the display is turned off output parameters are not sent to the display and all annunciators except ERROR and Shift are disabled Front panel operation is otherwise unaffected by turning off the display Stored in volatile memory e Sending a message to the display from the remote interface overrides the display state this means that you can display a message even if the display is turned off e The display state is automatically turned on when you return to the local front panel state Press the Shift key or execute LOCAL 710 from the remote interface to return to the local state DISPlay Query the front panel display setting Returns 0 OFF or 1 ON DISPlay TEXT lt quoted string gt Display a message containing up to 11 characters on the front panel any additional characters are truncated Commas periods and semicolons share a display space with the preceding character and are not considered individual characters When a message is displayed information relating to the output waveform such as frequency and amplitude is not sent to the display St
147. en off or after a remote interface reset The amplitude or dc offset is automatically adjusted and no error is generated if you change the output termination For example if you set the amplitude to 10 Vpp and then change the termination from 50 ohms to high impedance the displayed amplitude will double to 20 Vpp If you change from high impedance to 50 ohms the displayed amplitude will drop in half If you specify a 50 ohm termination but are actually terminating into an open circuit the displayed output will be twice the value specified For example if you set the offset to 100 mVdc and specify a 50 ohm termination but are actually terminating the output into an open circuit the actual displayed offset will be 200 mVdc Front Panel Operation Choose 50 OHM or HIGH Z from the front panel menu 1 OUT TERM SYS MENU Remote Interface Operation OUTPut LOAD 50 INFinity MINimum MAXimum 65 Chapter 3 Features and Functions Output Configuration Duty Cycle Applies only to square waves Duty cycle is specified as a percentage and represents the amount of time per cycle that the square wave is high T 1 Tp Duty Cycle frequency Ed where T e Duty cycle 20 to 80 in 1 increments frequency x 5 MHz 40 to 60 in 1 increments frequency gt 5 MHz The default is 50 e The duty cycle is stored in volatile memory the duty cycle is set to
148. enable bits in an enable register you must write a decimal value which corresponds to the binary weighted sum of the bits you wish to enable in the register 201 Chapter 4 Remote Interface Reference The SCPI Status Registers SCPI Status System Output Buffer Standard Event Lnable egister Status Byte o mmmpry Pensia Ly Summary Wegister Ln Not Used Bi nary Weights 25 1 2 2 22 4 2 8 2 16 25 32 2 7 Not d 202 Chapter 4 Remote Interface Reference The SCPI Status Registers The Status Byte Register The Status Byte summary register reports conditions from the other status registers Query data that is waiting in the function generator s output buffer is immediately reported through the message available bit bit 4 Bits in the summary register are not latched Clearing an event register will clear the corresponding bits in the Status Byte summary register Reading all messages in the output buffer including any pending queries will clear the message available bit Bit Definitions Status Byte Register Decimal Bit Value Definition 0 Not Used 1 Always set to 0 1 Not Used 2 Always set to 0 2 Not Used 4 Always set to 0 3 Not Used 8 Always set to 0 4 Message Available 16 Data is available in the output buffer 5 Standard Event 32 One or more bits are set in the Standard Ev
149. ency Deviation 1 078930044 Segment Value 1 0000 0 9402 0 2765 0 6362 1 0000 0 5829 0 9569 0 9897 0 3389 OANDOABRWNDN To Check Enable FM by sending the following commands FM STATE ON PM INT FREQ 555 555 DIAG PEEK 0 0 0 enter results lt Prescale S gt lt Points P gt 296 Specifications Chapter 8 Specifications Agilent 33120A Function Generator WAVEFORMS Standard Waveforms Sine Square Triangle Ramp Noise DC volts Sine x x Negative Ramp Exponential Rise Exponential Fall Cardiac Arbitrary Waveforms Waveform Length Amplitude Resolution Sample Rate Non Volatile Memory 8 to 16 000 points 12 bits including sign 40 MSa sec Four 16 000 point waveforms FREQUENCY CHARACTERISTICS Sine 100 Hz 15 MHz Square 100 uHz 15 MHz Triangle 100 Hz 100 kHz Ramp 100 Hz 100 kHz Noise Gaussian 10 MHz bandwidth Arbitrary Waveforms 8 to 8 192 points 8 193 to 12 287 points 12 288 to 16 000 points 100 uHz 5 MHz 100 uHz 2 5 MHz 100 uHz 200 kHz Resolution 10 wHz or 10 digits Accuracy 10 ppm in 90 days 20 ppm in 1 year 18 C 28 C Temperature Coefficient lt 2 ppm C Aging lt 10 ppm yr SINEWAVE SPECTRAL PURITY into 500 Harmonic Distortion DC to 20 kHz 70 dBc 20 kHz to 100 kHz 60 dBc 100 kHz to 1 MHz 45 dBc 1 MHz to 15 MHz 35 dBc Total Harmonic Di
150. ency 67 147 definition 66 front panel selection 22 remote interface selection 147 E Enter Number mode 3 38 ERROR annunciator 5 error interrupt example 261 errors 227 241 clearing 110 228 reading error queue 110 228 even parity RS 232 116 220 example programs remote interface AM waveform 252 APPLy command 248 arb waveform GPIB 255 arb waveform RS 232 267 burst modulation 248 damped sine wave 267 error interrupt 261 haversine 248 state storage 252 status registers 261 triggering 248 exponential fall waveform 175 exponential rise waveform 175 Ext annunciator 5 Ext Trig terminal 81 102 160 187 external source AM 75 156 burst modulation 82 164 FSK 93 169 sweep 97 173 external triggering 100 186 304 Index F factory setting baud rate RS 232 116 219 calibration security code 118 data bits RS 232 116 220 GPIB address 114 217 parity RS 232 116 220 firmware revision 113 190 floating point data 178 FM annunciator 5 FM modulation carrier frequency 78 carrier waveshape 77 modulating frequency 79 159 modulating waveshape 79 159 operational overview 157 peak frequency deviation 80 158 sync signal 79 technical description 288 FM DEV command 158 FM INT FREQ command 159 FM INT FUNC command 159 FM STAT command 159 FORM BORD command 185 FREQ command 146 FREQ STAR command 171 FREQ STOP command 171 frequency deviation FM 8
151. enerator Function Prototypes void rst_clear void void out_waveform void void command exe char commands int length void burst trig void void check error char func name BRR KKK KK RR KK KR RK KR KKK KKK ck ck ck ck ck ck ck ck ok ckckckckckckck ck ck ck ck ck ck ck ck ck KOK KK ko ke ke ke ke ke kJ void main void Start of main rst_clear Reset the instrument and clear error queue out waveform Set up burst modulation parameters burst trig Trigger the function generator BK RR RK KK RK RK RR KR A RR RRR RR RR KK ko ko ke ke ke ke ke ek void rst_clear void Reset the function generator clear the error queue and wait for commands to complete A 1 is sent to the output buffer from the OPC command when RST and CLS are completed float value IOOUTPUTS ADDR RST CLS OPC 15 IOENTER ADDR amp value X KR RK KR RK RR RK RK KR RR KKK RR KR ROKK KK ko ke kK 249 Chapter 6 Application Programs Using the APPLy Command continued void out_waveform void Set up the burst waveform with a burst count of 1 and a starting phase of 270 degrees The burst waveform is a 5 kHz sine wave with an output amplitude of 5 Vpp An offset voltage of 2 5 Vdc is added to create a haversine wave The triggered burst mode is used and the function generator will output a single burst when a bus trigger is rec
152. ent register bits must be enabled in enable register 6 Request Service 64 Requesting service serial poll 7 Not Used 128 Always set to 0 The Status Byte Summary Register is cleared when e You execute the CLS clear status command e Querying the Standard Event register ESR command will clear only bit 4 in the Summary Register The Status Byte Enable Register request service is cleared when e You execute the SRE 0 command e You turn on the power and have previously configured the function generator using the PSC 1 command e The enable register will not be cleared at power on if you have previously configured the function generator using PSC 0 203 Caution Chapter 4 Remote Interface Reference The SCPI Status Registers Using Service Request SRQ and Serial POLL You must configure your bus controller to respond to the IEEE 488 service request SRQ interrupt to use this capability Use the Status Byte enable register SRE command to select which summary bits will set the low level IEEE 488 service request signal When bit 6 request service is set in the Status Byte an IEEE 488 service request interrupt message is automatically sent to the bus controller The bus controller may then poll the instruments on the bus to identify which one requested service the instrument with bit 6 set in its Status Byte The request service bit is cleared only by reading the Status
153. entions 127 SYST BEEP command 189 SYST ERR command 189 209 SYST LOC command 200 SYST REM command 200 SYST RWL command 200 SYST VERS command 190 T table of contents 9 11 technical specifications 297 301 terminals Ext Trig FSK Burst 102 187 front panel overview 2 rear panel overview 6 termination output load front panel selection 40 65 remote interface selection 65 151 schematic diagram 281 text message calibration 122 errors 227 241 front panel display 112 188 times for download arb waveforms GPIB 299 arb waveforms RS 232 299 tone 189 triangle brackets gt syntax 127 Trig annunciator 5 TRIG SOUR command 165 173 186 TRIG SLOP command 187 TRIGGER command 101 186 triggering burst modulation 81 165 example program 248 external source 100 186 from the front panel 51 from the remote interface 186 internal 99 186 software bus 101 186 troubleshooting error messages 227 241 power on failure 16 RS 232 199 Turbo C 244 U units output amplitude front panel selection 64 remote interface selection 150 V vertical bar syntax 127 VOLT command 148 VOLT OFFS command 149 VOLT UNIT command 150 Vpk 64 150 Vpp 64 150 Vrms 64 150 W warranty information inside front cover waveforms ac attributes 283 arbitrary download 103 174 built in arbs 175 download speeds arbs 299 selecting ampli
154. equested output or carrier frequency exceeds the upper limit for the selected function This error applies only to the APPLy command See Output Frequency on page 57 for more information Data out of range offset The requested offset voltage exceeds the upper limit for the selected function or output amplitude This error applies only to the APPLy command See DC Offset Voltage on page 62 for more information Too much data A character string was received but could not be executed because the string length was more than 60 characters This error can be generated by the CALibration STRing and DISPlay TEXT commands 234 224 330 350 410 420 430 440 Chapter 5 Error Messages Execution Errors Illegal parameter value A discrete parameter was received which was not a valid choice for the command You may have used an invalid parameter choice Example DISP STAT XYZ XYZ is not a valid choice Self test failed The function generator s self test failed from the remote interface TST command In addition to this error one or more specific errors may be reported See also Self Test Errors on page 237 Too many errors The error queue is full because more than 20 errors have occurred No additional errors are stored until you remove errors from the queue The error queue is cleared when power has been off or after a CLS clear status command has been executed Query
155. ernal RATE MINimum MAXimum Query the burst rate Returns a value in hertz BM SOURce INTernal EXTernal Select the burst modulation source In the external gated burst mode the output waveform is either on or off based on the level of the external signal applied to the rear panel Ext Trig terminal The default is INT Stored in volatile memory e When the internal burst source is selected the external gated mode is disabled e When the external gate source is selected the output is enabled or disabled based on the logic level of the gate signal applied to the Ext Trig terminal When the gate signal is true TTL high the function generator outputs a continuous waveform When the gate signal is false TTL low the output is turned off zero volts or the dc offset level e When the external gate source is selected the burst count burst rate burst phase and burst trigger source are ignored these parameters are used for the triggered burst mode only BM SOURce Query the present burst modulation source Returns INT or EXT 164 Chapter 4 Remote Interface Reference Burst Modulation Commands BM STATe OFF ON Disable or enable burst modulation To ensure proper operation you should enable the burst mode after you have set up the other modulation parameters Only one modulation mode can be enabled at a time When you enable the burst mode the previous modulation mode is turned off BM
156. eshape is described by a finite number of horizontal points length it has been sampled in time or quantized causing a phase truncation error Spurious signals caused by phase truncation introduce jitter into the output waveform This may be regarded as time and phase displacement of output zero crossings Phase truncation causes phase modulation of the output signal which results in spurious harmonics see the equation below For lower output frequencies the phase accumulator periodically does not advance RAM addresses causing the DAC to deliver the same voltage as recorded on the previous clock cycle Therefore the phase slips back by 360 points before continuing to move forward again When RAM address increments are the same on each cycle of the output phase truncation error and jitter are essentially zero All standard waveshapes in the 33120A are generated with at least 16 000 waveform points which results in spurious signals below the wide band noise floor of the DAC Phase Truncation Harmonics lt 20 x log P dBc where P is the number of waveform points in RAM 277 Chapter 7 Tutorial Creating Arbitrary Waveforms Creating Arbitrary Waveforms For most applications it is not necessary to create a waveform of any specific length since the function generator will automatically sample the available data to produce an output signal In fact it is generally best to create arbitrary waveforms which
157. et GPIB address for function generator Function Prototypes void rst_clear void void setup status void void out waveform void void command exe char commands int length void check error char func name BRK KKK KK RK KR KK RK KK RR KK KR kc kc kckck ck ck ck ck ck ck ck ck ckckckckckckckck ck ck ck ck ck ck ck ck KKK OK KK ke ke ke ke ke ke J void main void Start of main rst_clear Reset the instrument and clear error queue setup status Set up 33120A status registers out waveform Set up frequency sweep parameters BK RR RK KR RR RK KK RK KR A RR RRR RR ROKK KK ke ke ke ke ke ek J 263 Chapter 6 Application Programs Using the Status Registers continued void rst_clear void Reset the function generator clear the error queue and wait for commands to complete A 1 is sent to the output buffer from the OPC command when RST and CLS are completed float value IOOUTPUTS ADDR RST CLS OPC 15 IOENTER ADDR amp value BK RK KK KR RR RK RR KK RK RK KR RRR RK RR KK RK KKK ke ke ke ke ke kk J void setup_status void An interrupt is to be generated whenever an error is detected To enable the status registers to generate an interrupt you must enable bits in the Status Byte and Standard Event Register Enable bit 5 Standard Event in the Status Byte to recognize activ
158. f supplied items Verify that you have received the following items with your function generator If anything is missing contact your nearest Agilent Technologies Sales Office One power cord One RS 232 serial cable vf This User s Guide One Service Guide One folded Quick Reference card Certificate of Calibration Agilent IntuiLink Arb Waveform Generation Software Connect the power cord and turn on the function generator The front panel display will light up while the function generator performs its power on self test The GPIB bus address is displayed Notice that the function generator powers up in the sine wave function at 1 kHz with an amplitude of 100 mV peak to peak into a 50 termination To review the power on display with all annunciators turned on hold down Shift as you turn on the function generator Perform a complete self test The complete self test performs a more extensive series of tests than those performed at power on Hold down Shift as you press the Power switch to turn on the function generator hold down the key for more than 5 seconds The self test will begin when you release the key If the self test is successful PASS is displayed on the front panel If the self test is not successful FAIL is displayed and the ERROR annunciator turns on See the Service Guide for instructions on returning the function generator to Agile
159. form is modulated with the external waveform The Ext annunciator turns on to indicate that the function generator is expecting a modulating signal on the rear panel AM Modulation terminal e You apply the external modulating waveform to the AM Modulation terminal The modulation depth is controlled by the signal level present 5 volts peak corresponds to 100 modulation AM SOURCe Query the modulating source Returns BOTH or EXT AM STATe OFF ON Disable or enable AM To ensure proper operation you should enable AM after you have set up the other modulation parameters Only one modulation mode can be enabled at a time When you enable AM the previous modulation mode is turned off AM STATe Query the state of AM Returns 0 OFF or 1 ON 156 en Chapter 4 Remote Interface Reference FM Modulation Commands FM Modulation Commands See also Frequency Modulation starting on page 76 in chapter 3 FM Overview The following is an overview of the steps required to generate an FM waveform The commands used for FM are listed on the next page Set up the carrier waveform Use the APPLy command or the equivalent FUNC SHAP FREQ VOLT and VOLT OFFS commands to select the function frequency amplitude and offset of the carrier waveform You can select a sine square triangle ramp or arbitrary waveform for the carrier Select the shape of the modulating waveform You can m
160. forms only e Ifyou attempt to set the carrier frequency to a value that is not valid the function generator will automatically adjust the frequency to the maximum value allowed with the present burst count From the front panel MAX VALUE is displayed and the carrier frequency is adjusted From the remote interface a 221 Settings conflict error is generated and the carrier frequency is adjusted 85 Carrier Frequency continued Chapter 3 Features and Functions Burst Modulation For all waveforms used with burst if the carrier frequency is set less than or equal to 100 Hz the following relationship applies Burst Count Carrier Frequency lt 500 seconds For Carrier lt 100 Hz If you attempt to set the carrier frequency to a value that is not valid the function generator will automatically adjust the frequency to the minimum value allowed with the present burst count From the front panel MIN VALUE is displayed and the frequency is adjusted From the remote interface a 221 Settings conflict error is generated and the frequency is adjusted For the triggered burst mode the sync signal is a TTL low while the specified number of cycles is output for the duration of the burst After the specified number of cycles has been output the sync signal goes high until the next burst The sync signal is output from the front panel SYNC terminal For the external gated burst mode the
161. fourth instrument configuration you cannot store to this memory location from the front panel However keep in mind that memory location 0 is automatically overwritten when the power is turned off Any arbitrary waveforms downloaded to VOLATILE memory are not remembered However if an arbitrary waveform is being output from non volatile memory when the state is stored the waveform data is stored The stored waveform is output when the instrument state is recalled If you delete an arbitrary waveform after storing the state the waveform data is lost and the function generator will not output the waveform when the state is recalled The SINC waveform is output in place of the deleted waveform When power is turned off the function generator automatically stores its state in memory location 0 You can configure the function generator to automatically recall the power down state when power is restored The recall mode is disabled when the function generator is shipped from the factory Select the POWER ON LAST STATE command from the SYS MENU to enable the power down recall mode Select POWER ON DEFAULT to disable the power down recall mode See Power Down Recall Mode on page 109 for more information 152 Chapter 4 Remote Interface Reference Output Configuration Commands RCL 0 1 2 3 Recall a previously stored state To recall a stored state you must use the same memory location used previously to
162. g FSK frequency shift keying modulation The rate at which the output shifts between the two frequencies called the carrier frequency and the hop frequency is determined by the internal rate generator or the signal level on the rear panel FSK terminal For this example you will set the carrier frequency to 3 kHz and the hop frequency to 500 Hz with an FSK rate of 100 Hz beet SS eee Select the function frequency and amplitude of the carrier For the carrier waveform you can select a sine square triangle ramp or arbitrary waveform For this example select a 3 kHz sine wave with an amplitude of 5 Vpp Enable FSK Notice that the FSK annunciator turns on Use the menu to set the hop frequency After you enable the FSK mode the recall menu key will automatically take you to the FSK FREQ command in the MOD MENU 44 Enter Shift lt Recall Menu 6 Chapter 2 Front Panel Menu Operation To output an FSK waveform Move down a level and set the hop frequency to 500 Hz Notice that the FSK annunciator flashes indicating that the displayed parameter is for the FSK mode Also notice that the hop frequency is displayed with fewer digits than the carrier frequency For more information on editing numbers in the menu refer to Menu Example 3 earlier in this chapter A500 0 Hz Save the change and turn off the menu At this point th
163. ge Notice that the Offset annunciator turns on all other annunciators are off indicating that a dc voltage is being output The annunciator will turn on when the offset is any value other than 0 volts 1155 0 mVDC You can also use the knob and arrow keys to enter a number See Front Panel Number Entry on page 3 for more information bo d Shift Store Enter In 2 HG Chapter 1 Quick Start To store the instrument state To store the instrument state You can store up to three different instrument states in non volatile memory This enables you to recall the entire instrument configuration with just a few key presses from the front panel The following steps show you how to store and recall a state Set up the function generator to the desired configuration The state storage feature remembers the function frequency amplitude dc offset duty cycle as well as any modulation parameters Turn on the state storage mode Three memory locations numbered 1 2 and 3 are available to store instrument configurations The instrument configuration is stored in non volatile memory and is remembered when power has been off This message appears on the display for approximately 10 seconds Repeat this step as needed Store the instrument state in memory location 2 9 Use the up and down arrow keys to select the memory location To cancel the store operation press
164. ge e g TRIGGER 710 186 Chapter 4 Remote Interface Reference Triggering e To ensure synchronization when the Bus source is selected send the WAI wait command When the WAI command is executed the function generator waits for all pending operations to complete before executing any additional commands For example the following command string guarantees that the first trigger is accepted and executed before the second trigger is recognized TRIG SOUR BUS TRG WAI TRG WAI e You can use the OPC operation complete query command or the OPC operation complete command to signal when the burst or sweep is complete The OPC command returns 1 to the output buffer when the burst or sweep is complete The OPC command sets the operation complete bit bit 0 in the Standard Event register when the burst or sweep is complete TRIGger SOURCe Query the present trigger source Returns IMM EXT or BUS TRIGger SLOPe POSitive NEGative Select the polarity of the Ext Trig terminal If you select POS the polarity of the Ext Trig terminal is the same as described on page 102 If you select NEG the polarity is the opposite of what is described The default is Positive Stored in volatile memory TRIGger SLOPe Query the present polarity of the Ext Trig terminal Returns POS or NEG TRG Trigger the function generator from the r
165. he function generator send the above command with the same code as used to unsecure calibration For example CAL SEC STAT ON HP033120 120 Chapter 3 Features and Functions Calibration Overview To Change the Security Code To change the security code you must first unsecure the function generator and then enter a new code Be sure to read the security code rules on page 118 before changing the security code Front Panel Operation To change the security code first make sure that the function generator is unsecured Select the PARAMETER level of the UNSECURED command enter the new security code and then press Enter Changing the code from the front panel also changes the code required from the remote interface Remote Interface Operation CALibration SECure CODE lt new code gt To change the security code first unsecure the function generator using the old security code Then enter the new code For example CAL SEC STAT OFF HP033120 Unsecure with old code CAL SEC CODE 22002133 Enter new code Calibration Count You can determine the number of times that your function generator has been calibrated Your function generator was calibrated before it left the factory When you receive your function generator read the count to determine its initial value The calibration count is stored in non volatile memory and does not change when power has been off or after a remote interface reset The
166. he triggered burst mode a TTL low signal is output while the specified number of cycles is output for the duration of the burst After the specified number of cycles has been output the sync signal goes high until the next burst e For the external gated burst mode the sync signal is a TTL high when the output is positive relative to zero volts or the dc offset value The signal is a TTL low when the output is negative relative to zero volts or the dc offset value e For FSK a momentary TTL high pulse gt 200 ns is output on the transition to the hop frequency e For frequency sweeps the sync signal is a TTL low at the start of the sweep when the start frequency is output and is a TTL high at the end of the sweep when the stop frequency is output e Remote Interface Operation OUTPut SYNC OFF ON Setting is stored in volatile memory 68 Chapter 3 Features and Functions Output Configuration Instrument State Storage You can store up to three different instrument states in non volatile memory This enables you to recall the entire instrument configuration with a single command from the remote interface or with just a few key presses from the front panel e Three memory locations numbered 1 2 and 3 are available to store instrument configurations The state storage feature remembers the function including arbitrary waveforms frequency amplitude dc off
167. he waveform from volatile memory to the specified name in non volatile memory The source for the copy is always VOLATILE you cannot copy from any other name and you cannot copy to VOLATILE The VOLATILE parameter is optional and can be omitted e The arb name may contain up to 8 characters The first character must be a letter A Z but the remaining characters can be numbers 0 9 or the underscore character Blank spaces are not allowed If you specify a name with more than 8 characters a 783 Arb waveform name too long error is generated e The following built in waveform names are reserved and cannot be used with the DATA COPY command SINC NEG_RAMP EXP_RISE EXP_FALL and CARDIAC If you specify one of the built in waveforms a 782 Cannot overwrite a built in arb waveform error is generated e The function generator does not distinguish between upper and lower case letters Therefore ARB_1 and arb_1 are the same name All characters are converted to upper case 182 Chapter 4 Remote Interface Reference Arbitrary Waveform Commands e Ifyou copy to a waveform name that already exists the previous waveform is overwritten no error is generated However you cannot overwrite any of the five built in waveforms e Up to four user defined waveforms can be stored in non volatile memory If memory is full and you try to copy a new waveform to non volatile memory a 781 Not enough memory e
168. heck for errors else printf No Errors Were Detected n n Use Serial Poll to read the Status Byte and clear all bits IOSPOLL ADDR amp stat cond BOK RR RR KK RK KR RR KK KR KKK RR RRR RK RR KKK KKK ok ko ke ke ke ke ke kJ 265 Chapter 6 Application Programs Using the Status Registers continued void command_exe char commands int length Execute one command string at a time using a loop int loop for loop 0 loop lt length loop IOOUTPUTS ADDR commands loop strlen commands loop BK RK KK KK RR RK KR RK KR KR KK RK RRR KR RK KKK KK ko ke ke ke ke ke ek J void check_error char func_name Read error queue to determine if errors have occurred char message 80 int length 80 IOOUTPUTS ADDR SYST ERR 9 Read the error queue IOENTERS ADDR message amp length Enter error string while atoi message 0 Loop until all errors are read printf Error s in function s n n message func_name IOOUTPUTS ADDR SYST ERR 9 IOENTERS ADDR message amp length BK RRR KK KK RRR KR KK RR RK KR RRR KK RR KKK KK KK ko ke KK J End of Program 4 266 Chapter 6 Application Programs Downloading an Arbitrary Waveform over RS 232 Downloading an Arbitrary Waveform over RS 232 sine wave BASIC RS 232 Program 5 10 20 30 40 50 60
169. ind this chapter useful whether you are operating the function generator from the front panel or over the remote interface Remote Interface Reference Chapter 4 contains reference information to help you program the function generator over the remote interface Error Messages Chapter 5 lists the error messages that may appear as you are working with the function generator Each listing contains enough information to help you diagnose and solve the problem Application Programs Chapter 6 contains several remote interface application programs to help you develop programs for your application Tutorial Chapter 7 discusses the fundamentals of signal generation and modulation techniques Specifications Chapter 8 lists the function generator s specifications For information on using the Phase Lock Option for the 38120A refer to the User s and Service Guide included with the Option 001 If you have questions relating to the operation of the 33120A call 1 800 452 4844 in the United States or contact your nearest Agilent Technologies Sales Office If you believe your 33120A has failed refer to Operating Checklist Types of Service Available and Repackaging for Shipment at the beginning of chapter 6 in the 33120A Service Guide Contents Chapter 1 Quick Start To prepare the function generator for use 15 If the function generator does not turn on 16 To adjust the carrying handle 18 To set the
170. ingle to enable the single trigger mode also enables the external trigger mode The Trig annunciator turns on when the function generator is waiting for an external trigger The front panel Single key is disabled when in remote e Remote Interface Operation TRIGger SOURce EXTernal 100 Chapter 3 Features and Functions Triggering Software Bus Triggering The bus trigger mode is available only from the remote interface This mode is similar to the single trigger mode from the front panel but you trigger the function generator by sending a bus trigger command The function generator outputs one burst or initiates one sweep each time the trigger command is received e To select the bus trigger source send the following command TRIGGER SOURCE BUS e To trigger the function generator from the remote interface GPIB or RS 232 send the TRG trigger command e You can also trigger the function generator from the GPIB interface by sending the IEEE 488 Group Execute Trigger GET message The following statement shows how to send a GET using BASIC TRIGGER 710 Group Execute Trigger e The following statement shows how to send a trigger from the GPIB interface using the GPIB Command Library for C or QuickBASIC OTRIGGER 710 101 Chapter 3 Features and Functions Triggering Ext Trig FSK Burst Input Terminal Ext Trig INPUT FSK Burst 5V 5V oV gt us
171. interface However you cannot edit any of the five built in arbitrary waveforms Use the GET option under the NEW ARB command in the EDIT MENU to load an existing user defined waveform Then use the LINE EDIT POINT EDIT and INVERT commands to edit the waveform e The INVERT command in the EDIT MENU takes the inverse of each point in the specified waveform by changing the sign e Youcan use the DELETE command in the EDIT MENU to delete any user defined waveforms in volatile memory A list of all user defined waveforms appears when you move to the DELETE command 108 Chapter 3 Features and Functions System Related Operations System Related Operations This section gives information on topics such as power down recall self test error conditions and front panel display control This information is not directly related to waveform generation but is an important part of operating the function generator Power Down Recall Mode When power is turned off the function generator automatically stores its state in memory location 0 You can configure the function generator to automatically recall the power down state when power is restored The recall mode is disabled when the function generator is shipped from the factory The power down recall mode can be set from the front panel only e When the recall mode is disabled factory setting the function generator powers up in its default configuration see page 123
172. ion pre scaler divider S E truncated to integer value gt 1 Compute the number of points for the modulation waveform length 2xC P 8 x F rounded down to even number Waveshapes are automatically expanded or compressed to match length P computed above and downloaded into modulation RAM Example Assume that you need to phase continuously frequency hop between the following nine frequencies every 200 us 15 0 MHz 1 001 MHz 9 780 MHz 12 375 MHz 0 5695 MHz 3 579 MHz 0 8802 MHz 0 6441 MHz and 10 230 MHz Solution Create a modulation arbitrary waveform that is precisely sampled in FM modulation F 1 9x 200 us 555 555 Hz modulation frequency Round down in sixth digit to get modulation frequency to set S 624 555 555 1 1232 truncate to 1 2xC P 148 x F rounded down to even number 295 Chapter 7 Tutorial Modulation e Set the modulation frequency to 555 555 Hz e Set the carrier frequency to Max F Min F 2 7 784750 MHz e Set deviation pk frequency to Max F Min F 2 7 215250 MHz e Create and download a nine segment arbitrary waveform with the values shown below Each segment is 250 points long 2250 9 for a total of 2 250 points Use the DATA VOLATILE command download to achieve 12 bit frequency resolution for each point y is the new vertical value y mX b m 1 Deviation X is the original frequency point b carrier frequ
173. ion readback failed Waveform ASIC failed SYNC signal detection failure Bessel filter path SYNC signal detection failure Elliptic filter path T O processor does not respond I O processor failed self test 237 701 702 703 704 705 706 707 708 709 760 Chapter 5 Error Messages Calibration Errors Calibration Errors The following errors indicate failures that may occur during a calibration Refer to the Service Guide for more information Cal security disabled by jumper The calibration security feature has been disabled with a jumper inside the function generator When applicable this error will occur at power on to warn you that the function generator is unsecured Cal secured The function generator is secured against calibration Invalid secure code An invalid calibration security code was received when attempting to unsecure or secure the function generator You must use the same security code to unsecure the function generator as was used to secure it and vice versa The security code may contain up to 12 alphanumeric characters The first character must be a letter Secure code too long A security code was received which contained more than 12 characters Cal aborted A calibration in progress is aborted when you press any front panel key send a device clear or change the local remote state of the instrument Cal value out of range The specified calibration value CAL VALUE is
174. irect digital synthesis DDS signal generator differs from a digital audio player because of its very precise control of the data stream input to the DAC In a DDS system the amplitude values for one complete cycle of the output waveshape are stored sequentially in random access memory RAM as shown in the figure below As RAM addresses are changed the DAC converts the waveshape data into a voltage waveform whose data values are loaded in RAM The frequency of the voltage waveform is proportional to the rate at which the RAM addresses are changed The 33120A represents amplitude values by 4 096 discrete voltage levels or 12 bit vertical resolution Waveforms may contain between 8 points and 16 000 points of 12 bit amplitude values The number of points in RAM representing one complete cycle of the waveshape or 360 is called its length or horizontal resolution Each RAM address corresponds to a phase increment equal to 360 points where points is the waveform length Therefore sequential RAM addresses contain the amplitude values for the individual points 0 to 360 of the waveform 0 90 180 270 360 t t t m 4096 x CR x 2047 DAC Codes X 7 Jf No uu v 0 t t t 0 3 999 7 999 11 999 15 999 Memory Address Points 274 Chapter 7 Tutorial Direct Digital Synthesis Direct digital synthesis DDS generators use a phase accumulation technique to control waveform RAM addressing Instead of using a
175. it the displayed output will be twice the value specified For example if you set the offset to 100 mVdc and specify a 50 ohm termination but are actually terminating the output into an open circuit the actual displayed offset will be 200 mVdc OUTPut LOAD MINimum MAXimum Query the output impedance Returns 50 or 9 9E 37 OUTPut SYNC OFF ON Disable or enable output from the SYNC terminal The default is ON When the sync signal is disabled the output level on the SYNC terminal is indeterminate it might be a TTL high or a TTL low Stored in volatile memory See SYNC Signal on page 68 in chapter 3 for more information on the SYNC signal provided for each of the output functions OUTPut SYNC Query the state of the SYNC terminal Returns 0 OFF or 1 ON 151 Chapter 4 Remote Interface Reference Output Configuration Commands sav 0 1 2 3 Store up to four different instrument configurations Stored in non volatile memory Four memory locations numbered 0 1 2 and 3 are available to store instrument configurations The state storage feature remembers the function including arbitrary waveforms frequency amplitude dc offset duty cycle as well as any modulation parameters To recall a stored state you must use the same memory location used previously to store the state From the remote interface only you can use memory location 0 to store a
176. ity from the Standard Event Register 2 5 32 IOOUTPUTS ADDR SRE 32 7 Enable bits 2 3 4 and 5 in the Standard Event Register to interrupt the Status Byte 2 2 2 3 2 4 2 5 60 IOOUTPUTS ADDR ESE 60 7 BK RK KKK RRR KKK RK KR KKK KR RRR KK RR RR RK KK ko ke KK J 264 Chapter 6 Application Programs Using the Status Registers continued void out waveform void Configure the waveform and enable FM modulation The carrier waveform is a 5 kHz sine wave and the modulating waveform is a 500 Hz sine wave The peak frequency deviation is 250 Hz float value int stat cond static char cmd_string OUTP LOAD 50 Output termination is 50 ohms APPL SIN 5000 5 Carrier waveshape is sine wave output frequency is 5 kHz 5 Vpp FM INT FUNC SIN Modulating waveshape is sine wave FM INT FREQ 500 Modulating frequency is 500 Hz FM DEV 250 Frequency deviation is 250 Hz s Call the function to execute the command strings shown above command exe cmd string sizeof cmd string sizeof char Turn sweep on and send 1 to output buffer when setup is complete IOOUTPUTS ADDR FM STAT ON OPC 17 IOENTER ADDR amp value Determine the status of the SRQ line return 1 if error occurred IOSTATUS ISC 1 amp stat cond if stat cond check error out waveform Call function to c
177. ived than were expected for the command You may have entered an extra parameter or you added a parameter to a command that does not accept a parameter Example APPL 10 Missing parameter Fewer parameters were received than were expected for the command You omitted one or more parameters that are required for the command Example OUTP LOAD Program mnemonic too long A command header was received which contained more than the maximum 12 characters allowed Example OUTP SYNCHRONIZATION ON 229 113 121 123 124 128 131 138 148 Chapter 5 Error Messages Execution Errors Undefined header A command was received that is not valid for the function generator You may have misspelled the command or it may not be a valid command If you are using the short form of the command remember that it may contain up to four letters Example TRIGG SOUR BUS Invalid character in number An invalid character was found in the number specified for a parameter value Example ESE B01010102 Exponent too large A numeric parameter was found whose exponent was larger than 32 000 Example BMOD NCYC 1534000 Too many digits A numeric parameter was found whose mantissa contained more than 255 digits excluding leading zeros Numeric data not allowed A numeric parameter was received but a character string was expected Example DISP TEXT 123 Invalid suffix A suffix was inc
178. k ck ck ck ck ck ckckckckckckck ck ck ck ck ck ck ck ck ck ok ok KK ko ke ke ke ke ke kJ 258 Chapter 6 Application Programs Downloading an Arbitrary Waveform over GPIB continued void out_waveform void Set the output frequency to 5 kHz with an amplitude of 10 Vpp and output the arbitrary waveform static char cmd_string Copy arb waveform to non volatile memory with name PULSE DATA COPY PULSE VOLATILE FUNC USER PULSE Select the active arb waveform FUNC SHAP USER Output the selected arb waveform um Call the function to execute the command strings shown above command exe cmd string sizeof cmd string sizeof char Call the function to check for errors check error out waveform BK RR KK KR KKK RK RK KK ko kk kc kckck kk ck ck ckck ck ck ok ckckckckckck ck ck ck ck ck ck ck ck KKK KK ko ke ke ke ke kk J void command exe char commands int length Execute one command string at a time using loop int loop for loop 0 loop lt length loop IOOUTPUTS ADDR commands loop strlen commands loop Set output termination to 50 ohms and output frequency to 5 kHz 5 Vpp IOOUTPUTS ADDR OUTP LOAD 50 12 IOOUTPUTS ADDR FREQ 5000 VOLT 5 16 BK RK KK KK RRR KR RK KR KKK KK koc kc kc kckckck ck ck ck ck ck ck ck ck ck RR ck ck ck ck ck ck ck ck ck ok ok ok ok ko ke ke ke ke ke ke J
179. l To connect the function generator to a computer or terminal you must have the proper interface cable Most computers and terminals are DTE Data Terminal Equipment devices Since the function generator is also a DTE device you must use a DTE to DTE interface cable These cables are also called null modem modem eliminator or crossover cables The interface cable must also have the proper connector on each end and the internal wiring must be correct Connectors typically have 9 pins DB 9 connector or 25 pins DB 25 connector with a male or female pin configuration A male connector has pins inside the connector shell and a female connector has holes inside the connector shell If you cannot find the correct cable for your configuration you may have to use a wiring adapter If you are using a DTE to DTE cable make sure the adapter is a straight through type Typical adapters include gender changers null modem adapters and DB 9 to DB 25 adapters Refer to the cable and adapter diagrams on the following page to connect the function generator to most computers or terminals If your configuration is different than those described order the 34399A Adapter Kit This kit contains adapters for connection to other computers terminals and modems Instructions and pin diagrams are included with the adapter kit 196 Chapter 4 Remote Interface Reference RS 232 Interface Configuration DB 9 Serial Connection If your
180. l errors are read printf Error s in function s n n message func_name IOOUTPUTS ADDR SYST ERR 9 IOENTERS ADDR message amp length BR KK KK RR RK KK RK KR KK KK RR KK a ck ck ck ck ck ck RK KOK RR KKK KOK KK ko ko KK void burst trig void Trigger the function generator to output a single burst To output a continuous burst change the trigger source to IMMediate To change the trigger source send TRIG SOUR IMM in the out_waveform function IOOUTPUTS ADDR TRG 4 or IOTRIGGER ADDR BK RR RK KR RR RK RR RK RR KK RRR KR RR ROKK KK ko ke ke ke ke ke kJ End of Program 1 251 Chapter 6 Application Programs Using the Low Level Commands Using the Low Level Commands This program teaches the following concepts e How to use the low level commands to set up an AM waveform e How to use the SAV command to store the instrument configuration in memory BASIC GPIB Program 2 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 This program uses low level SCPI commands to configure the function generator to output an AM waveform This program also shows how to use state storage to store the instrument configuration in memory CLEAR 7 Clear interface send device clear ASSIGN Fgen TO 710 Assign I O path to address 710 OUTPUT Fgen RST Reset the function generator UT
181. l tests pass you can have a high confidence that the function generator is fully operational If the complete self test is successful PASS is displayed on the front panel If the self test fails FAIL is displayed and the ERROR annunciator turns on See the Service Guide for instructions on returning the function generator to Agilent for service Front Panel Operation 4 TEST SYS MENU Another way to perform the complete self test from the front panel is as follows Hold down Shift as you press the Power switch to turn on the function generator hold down the key for more than 5 seconds The self test will begin when you release the key Remote Interface Operation aT ST 2 Returns 0 if the self test passes or 1 if it fails If the self test fails an error message is also generated with additional information on why the test failed 111 Chapter 3 Features and Functions System Related Operations Display Control To speed up the rate at which the function generator can make configuration changes or for security reasons you may want to turn off the front panel display From the remote interface you can also display a message containing up to 11 characters on the front panel The display can be enabled disabled from the remote interface only When the display is turned off output parameters are not sent to the display and all annunciators except ERROR and Shift are disabled Front panel
182. latile memory You are then exited from the menu Move across to the SAVE AS command on this level 6 SAVE AS mM 06 Chapter 3 Features and Functions Arbitrary Waveforms v 19 Move down a level to save the waveform in non volatile memory At this point the pulse waveform is being output from volatile memory You can store up to four user defined waveforms in non volatile memory From the front panel you can save the waveform using one of the following names ARB1 ARB2 ARB3 or ARBA ARB1 NEW Enter 20 Save the waveform and turn off the menu The function generator beeps and displays a message to show that the waveform is being saved You are then exited from the menu SAVING The waveform is now stored in non volatile memory and is output from the function generator The name that you used to store the waveform should appear in the waveform list press Arb List 107 Chapter 3 Features and Functions Arbitrary Waveforms Additional Information on Arbitrary Waveforms e Press the Arb key to output the arbitrary waveform currently selected to scroll through the waveform choices and make a selection press Arb List e In addition to creating a new arbitrary waveform from the front panel you can also edit any existing user defined waveforms You can edit waveforms created either from the front panel or from the remote
183. lect the remote interface The function generator is shipped with both an GPIB IEEE 488 interface and an RS 232 interface Only one interface can be enabled at a time The GPIB interface is selected when the function generator is shipped from the factory See also Remote Interface Selection on page 115 Turn on the menu A MOD MENU Move across to the I O MENU choice on this level E I O MENU Move down a level and then across to the INTERFACE choice 2 INTERFACE Move down to the PARAMETER level to select the interface Use the left right arrow keys to see the interface choices Choose from the following HPIB 488 or RS 232 HPIB 488 Save the change and turn off the menu The interface selection is stored in non volatile memory and does not change when power has been off or after a remote interface reset N 18 Shift Menu On Off Enter Chapter 4 Remote Interface Reference To set the baud rate To set the baud rate You can select one of six baud rates for RS 232 operation The rate is set to 9600 baud when the function generator is shipped from the factory See also Baud Rate Selection on page 116 Turn on the menu A MOD MENU Move across to the I O MENU choice on this level E I O MENU Move down a level and then across to the BAUD RATE choice 3 BAUD RATE Move down to the PARAMET
184. liance by sending a query from the remote interface The SCPI version can be queried from the remote interface only e Remote Interface Operation SYSTem VERSion Returns a string in the form YYYY V where the Y s represent the year of the version and the V represents a version number for that year for example 1993 0 117 Chapter 3 Features and Functions Calibration Overview Calibration Overview This section gives an overview of the calibration features of the function generator For a more detailed discussion of the calibration procedures see chapter 4 in the Service Guide Calibration Security This feature allows you to enter a security code to prevent accidental or unauthorized calibrations of the function generator When you first receive your function generator it is secured Before you can calibrate the function generator you must unsecure it by entering the correct security code e The security code is set to HP033120 when the function generator is shipped from the factory The security code is stored in non volatile memory and does not change when power has been off or after a remote interface reset e To secure the function generator from the remote interface the security code may contain up to 12 alphanumeric characters as shown below The first character must be a letter but the remaining characters can be letters or numbers You do not have to use all 12 characters but the fi
185. libration message CAL STR CAL 12 10 93 122 Chapter 3 Features and Functions Power On and Reset State Power On and Reset State The parameters marked with a bullet e are stored in non volatile memory The factory settings are shown NOTE The power on state will be different if you have enabled the power down recall mode See Power Down Recall Mode on page 109 for more information Output Configuration Function Frequency Amplitude into 50 ohms Offset Output Units Output Termination Modulation AM Carrier Waveform AM Modulating Waveform AM Depth FM Carrier Waveform FM Modulating Waveform FM Peak Frequency Deviation Burst Carrier Frequency Burst Count Burst Rate Burst Starting Phase FSK Carrier Waveform FSK Hop Frequency FSK Rate Modulation State Sweep Start Stop Frequency Sweep Time Sweep Mode System Related Operations e Power Down Recall Display Mode e Comma Separators Triggering Operations Trigger Source Input Output Configuration e GPIB Address e Interface e Baud Rate e Parity Calibration Calibration State Power On Reset State Sine wave 1 kHz 100 mV peak to peak 0 00 Vdc Volts peak to peak 50 ohms Power On Reset State 1 kHz Sine wave 100 Hz Sine wave 100 1 kHz Sine wave 10 Hz Sine wave 100 Hz 1 kHz Sine wave 1 cycle 100 Hz 0 degrees 1 kHz Sine wave 100 Hz Sine wave 10 Hz Off 100 Hz 1 kHz 1 second Linear Power On Rese
186. lid Negative offset gain cal required CAL SETup 50 Flatness DAC gain cal required CAL SETup 64 AM cal 1 required CAL SETup 30 AM cal 2 required CAL SETup 31 Cal load resistance not specified CAL SETup 33 Square wave positive offset cal required CAL SETup 60 Square wave 50 duty cycle cal required CAL SETup 62 AM cal 3 required CAL SETup 32 239 780 781 782 783 784 Chapter 5 Error Messages Arbitrary Waveform Errors Arbitrary Waveform Errors The following errors indicate failures that may occur during an arbitrary waveform download Refer to Arbitrary Waveform Commands starting on page 174 for more information VOLATILE arb waveform has not been loaded The DATA COPY command copies the waveform downloaded into VOLATILE memory to the specified name You must download the waveform using the DATA VOLATILE or DATA DAC VOLATILE command prior to a copy operation Not enough memory to store new arb waveform use DATA DELete Up to four user defined waveforms can be stored in non volatile memory Use the DATA DEL command to delete the waveform in VOLATILE memory or any of the four user defined waveforms in non volatile memory Use the DATA CAT command to list all waveforms currently stored in volatile and non volatile memory Cannot overwrite a built in arb waveform You cannot overwrite the names of the five built in arbitrary waveforms The following names
187. limited if the data points do not span the full range of the output DAC Digital to Analog Converter For example the built in SINC waveform does not use the full range of values between 1 and therefore its maximum amplitude is 6 084 Vpp into 50 ohms e You can set the units for output amplitude to Vpp Vrms or dBm See the VOLT UNIT command for more information e For dc volts the output level is actually controlled by setting the offset voltage You can set the dc voltage to any value between 5 Vdc into 50 ohms or 10 Vdc into an open circuit See the VOLT OFFS command for more information 148 Chapter 4 Remote Interface Reference Output Configuration Commands e Possible Conflict with Function Change The output amplitude is automatically adjusted if you select a function whose maximum amplitude is less than that of the currently active function This conflict may arise when the output units are Vrms or dBm due to the differences in crest factor for the output functions For example if you output a 5 Vrms square wave into 50 ohms and then change the function to sine wave the function generator will adjust the output amplitude to 3 535 Vrms the upper limit for sine waves in Vrms From the remote interface a 221 Settings conflict error is generated and the amplitude is adjusted e Output Amplitude and Output Termination The output amplitude is automatically adjusted and no error is generated if you
188. litude range depends on the function currently selected and the output termination The default amplitude is 100 mVpp into 50 ohms for all functions Output Minimum Maximum Function Termination Amplitude Amplitude Sine 500 50 mVpp 10 Vpp Square 500 50 mVpp 10 Vpp Triangle 500 50 mVpp 10 Vpp Ramp 500 50 mVpp 10 Vpp Noise 500 50 mVpp 10 Vpp Built In Arbs 1 500 50 mVpp 10 Vpp Sine Open Circuit 100 mVpp 20 Vpp Square Open Circuit 100 mVpp 20 Vpp Triangle Open Circuit 100 mVpp 20 Vpp Ramp Open Circuit 100 mVpp 20 Vpp Noise Open Circuit 100 mVpp 20 Vpp Built In Arbs 1 Open Circuit 100 mVpp 20 Vpp 1 There are five built in arbitrary waveforms stored in non volatile memory sinc negative ramp exponential rise exponential fall and cardiac e For arbitrary waveforms the maximum amplitude will be limited if the data points do not span the full range of the output DAC Digital to Analog Converter For example the built in SINC waveform does not use the full range of values between 1 and therefore its maximum amplitude is 6 084 Vpp into 50 ohms Possible Conflict with Function Change The output amplitude is automatically adjusted if you select a function whose maximum amplitude is less than that of the currently active function This conflict may arise when the output units are Vrms or dBm due to the differences in crest factor for the output functions For example if you output a 5 Vrms square wave into 50
189. m When a low TTL level is present the output is disabled The Ext annunciator turns on when selected 102 Shift Menu On Off In Chapter 3 Features and Functions Arbitrary Waveforms Arbitrary Waveforms There are five built in arbitrary waveforms stored in non volatile memory You can also download up to four user defined waveforms into non volatile memory Each waveform can contain between 8 and 16 000 data points Refer to chapter 7 Tutorial for more information on the internal operation of downloading and outputting an arbitrary waveform Creating and Storing an Arbitrary Waveform This section gives an example which shows you how to create and store an arbitrary waveform from the front panel To download an arbitrary waveform from the remote interface see Arbitrary Waveform Commands starting on page 174 For this example you will create and store a pulse waveform containing 400 points Turn on the menu A MOD MENU Move across to the EDIT MENU choice on this level C EDIT MENU Move down a level to the NEW ARB command There are seven command choices available in the EDIT MENU However you can access only two of the choices NEW ARB and DELETE until you either clear volatile memory or load an existing user defined waveform 1 NEW ARI i 103 Chapter 3 Features and Functions Arbitrary Waveforms v 4 Move down a level to the
190. main void Start of main rst_clear Reset the instrument and clear error queue get_data Calculate the waveform data points out waveform Download points and output arb waveform BK RR RK KK RR RK KR RK KKK KK RK RRR KOK RR KR KKK OK KK ke ke ke ke ke kJ void rst_clear void Reset the function generator clear the error queue and wait for commands to complete A 1 is sent to the output buffer from the OPC command when RST and CLS are completed float value IOOUTPUTS ADDR RST CLS OPC 15 IOENTER ADDR amp value BK RRR RK KK RK KR KK RR KKK RRR ROKR RK KKK KK ko ke ke ke ke ke kJ void get_data void Load 4000 points into an array to set the rise time and fall time to 250 ns and the pulse width to 10 us the output frequency is set to 5 kHz in the out_waveform function float waveform int loop num_points 4000 waveform float malloc num points sizeof float for loop 1 loop lt 5 loop waveform loop float loop 1 5 Set rise time 5 points for loop 6 loop lt 205 loop waveform loop 1 Set pulse width 10 points for loop 206 loop lt 210 loop waveform loop float 210 loop 5 Set fall time 5 points 257 Chapter 6 Application Programs Downloading an Arbitrary Waveform over GPIB continued for loop 211
191. mand syntax or hardware errors have been detected A record of up to 20 errors can be stored in the function generator s error queue See chapter 5 Error Messages for a complete listing of the errors e Errors are retrieved in first in first out FIFO order The first error returned is the first error that was stored When you have read all errors from the queue the ERROR annunciator turns off The function generator beeps once each time an error is generated e Ifmore than 20 errors have occurred the last error stored in the queue the most recent error is replaced with 350 Too many errors No additional errors are stored until you remove errors from the queue If no errors have occurred when you read the error queue the function generator responds with 0 No error e The error queue is cleared when power has been off or after a CLS clear status command has been executed The RST reset command does not clear the error queue CLS Clear the Status Byte summary register and all event registers ESE lt enable value gt Enable bits in the Standard Event enable register The selected bits are then reported to the Status Byte ESE Query the Standard Event enable register The function generator returns a decimal value which corresponds to the binary weighted sum of all bits set in the register ESR Query the Standard event register The function generator returns a decimal value which correspon
192. mory This program uses the arbitrary waveform function to download and output a square wave pulse with a calculated rise time and fall time The waveform consists of 4000 points downloaded to the function generator as ASCII data OPTION BASE 1 DIM Waveform 4000 INTEGER I CLEAR 7 ASSIGN Fgen TO 710 OUTPUT Fgen RST FOR I 1 TO 5 Waveform I I 1 5 NEXT I FOR I 6 TO 205 Waveform I 1 NEXT I FOR I 206 TO 210 Waveform I 2 210 1 5 NEXT I FOR I 211 TO 4000 Waveform I z0 NEXT I Dimension array with 4000 elements Declare integer variable Clear interface send device clear Assign I O path to address 710 Reset the function generator Set rise time 5 points Set pulse width 200 points Set fall time 5 points Set remaining points to zero 255 Chapter 6 Application Programs Downloading an Arbitrary Waveform over GPIB continued 300 Download data points to volatile memory from array 310 320 DISP Downloading Arb 330 OUTPUT Fgen DATA VOLATILE Waveform 340 DISP Download Complete 350 360 OUTPUT Fgen DATA COPY PULSE VOLATILE Copy arb to non volatile memory 370 OUTPUT Fgen FUNC USER PULSE Select the active arb waveform 380 OUTPUT Fgen FUNC SHAP USER Output the selected arb waveform 390 400 OUTPUT Fgen OUTP LOAD 50 Output termination is 50 ohm
193. mote Interface Reference The SCPI Status Registers The SCPI Status Registers The function generator uses the Status Byte register group and the Standard Event register group to record various instrument conditions A diagram of the SCPI status system is shown on the next page An example program is included in chapter 6 Application Programs which shows the use of the status registers You may find it useful to refer to the program after reading the following section in this chapter What is an Event Register An event register is a read only register that reports defined conditions within the function generator Bits in an event register are latched When an event bit is set subsequent state changes are ignored Bits in an event register are automatically cleared by a query of that register or by sending the CLS clear status command The RST reset command or device clear will not clear bits in an event register Querying an event register returns a decimal value which corresponds to the binary weighted sum of all bits set in the register What is an Enable Register An enable register defines which bits in the corresponding event register are logically ORed together to form a single summary bit You can read from and write to an enable register Querying an enable register will not clear it The CLS clear status command does not clear enable registers but it does clear the bits in the event registers To
194. ms Frequency Change 3 30 ms Amplitude Change 30 ms Offset Change 10 ms Select User Arb 100 ms Modulation Parameter Change 350 ms Arb Download Times over GPIB Arb Length Binary ASCII Integer ASCII Real 4 16 000 points 8 sec 81 sec 100 sec 8 192 points 4 sec 42 sec 51 sec 4 096 points 2 5 sec 21 sec 26 sec 2 048 points 1 5 sec 11 sec 13 sec Arb Download Times over RS 232 at 9600 Baud 5 Arb Length Binary ASCII Integer ASCII Real 6 16 000 points 35 sec 101 sec 134 sec 8 192 points 18 sec 52 sec 69 sec 4 096 points 10 sec 27 sec 35 sec 2 048 points 6 sec 14 sec 18 sec 1 Trigger source ignored when External Gate is selected 2 Time to change parameter and output the new signal 8 Modulation or sweep off 4 Times for 5 digit and 12 digit numbers b For 4800 baud multiply the download times by two For 2400 baud multiply the download times by four etc 6 Time for 5 digit numbers For 12 digit numbers multiply the 5 digit numbers by two 299 Chapter 8 Specifications Agilent 33120A Function Generator GENERAL SPECIFICATIONS Power Supply 1 Power Line Frequency Power Installation Power Consumption Operating Environment Storage Environment State Storage Memory Dimensions W x H x D Bench Top Rack Mount Weight 100V 120V 220V 240V 10 switch selectable 50 Hz to 60 Hz 10 and 400 Hz 10 Automatically sen
195. n the gate signal is false TTL low the output is turned off zero volts or the dc offset level e When the external gate source is selected the burst count burst rate burst phase and burst trigger source are ignored these parameters are used for the triggered burst mode only e The Ext annunciator turns on when the function generator is waiting for the external gate signal e Front Panel Operation 7 BURST SRC MOD MENU e Remote Interface Operation BM SOURce INTernal EXTernal 83 Chapter 3 Features and Functions Burst Modulation To Select Burst Modulation e The Burst annunciator turns on when burst modulation is enabled e Only one modulation mode can be enabled at a time When you enable the burst mode the previous modulation mode is turned off e Front Panel Operation Enable burst modulation before you set up the other modulation parameters Press Shift Burst to output the burst using the present settings for the carrier frequency output amplitude and offset voltage e Remote Interface Operation To ensure proper operation you should enable the burst mode after you have set up the other modulation parameters BM STATe OFF ON Burst Carrier Frequency The carrier frequency defines the repetition rate of the burst waveform in the triggered and external gated modes In the triggered mode the number of cycles specified by the burst count are output at the f
196. ncy From the front panel MAX VALUE is displayed and the deviation is adjusted From the remote interface a 221 Settings conflict error is generated and the deviation is adjusted The sum of the carrier frequency and peak frequency deviation must be less than or equal to the maximum frequency for the selected function plus 100 kHz 15 1 MHz for sine and square 200 kHz for triangle and ramp and 5 1 MHz for arbitrary waveforms If you attempt to set the deviation to a value that is not valid the function generator will automatically adjust the deviation to the maximum value allowed with the present carrier frequency From the front panel MAX VALUE is displayed and the deviation is adjusted From the remote interface a 221 Settings conflict error is generated and the deviation is adjusted Front Panel Operation Press Shitt Level to set the peak deviation the value is displayed for approximately 10 seconds Before setting the deviation from the front panel you must have FM enabled If you attempt to set the deviation when FM is not enabled SELECT AM FM is displayed Remote Interface Operation FM DEViation peak deviation in Hz MINimum MAXimum 80 Chapter 3 Features and Functions Burst Modulation Burst Modulation You can configure the function generator to output a waveform with a specified number of cycles called a burst You can output the burst at
197. nd then execute the OPC operation complete command as the last command When the command sequence is completed the operation complete bit bit 0 is set in the Standard Event register Use a serial poll to check to see when bit 5 standard event is set in the Status Byte summary register You could also configure the function generator for an SRQ interrupt by sending SRE 32 Status Byte enable register bit 5 206 Chapter 4 Remote Interface Reference The SCPI Status Registers The Standard Event Register The Standard Event register reports the following types of instrument events power on detected command syntax errors command execution errors self test or calibration errors query errors or when an OPC command is executed Any or all of these conditions can be reported in the Standard Event summary bit through the enable register To set the enable register mask you write a decimal value to the register using the ESE event status enable command An error condition Standard Event register bits 2 3 4 or 5 will always record one or more errors in the function generator s error queue Read the error queue using the SYSTem ERRor command Bit Definitions Standard Event Register Bit 0 Operation Complete Not Used 2 Query Error 3 Device Error 4 Execution Error 5 Command Error 6 Not Used 7 Power On Decimal Value 1 2 4 16 32 64 128 Definiti
198. nerator incorporates a second lower speed and lower resolution DDS arbitrary waveform generator to produce the modulating signal independent of the carrier signal Internal modulation waveshapes range in length from 2 048 points to 4 096 points User defined arbitrary waveforms are automatically expanded or compressed in length as needed to fit within the required modulation waveform constraints Linear interpolation is performed on user defined arbitrary waveforms while the lengths of standard waveshapes are varied by decimation Due to the modulation sample rate and waveform size limitations the best case modulation signal frequency accuracy is approximately 0 05 of setting Unlike the main signal output discussed previously modulation waveshapes are sampled using a variable point clock to sample data loaded in modulation waveform RAM Internally the modulation point clock C and modulation waveform length are automatically adjusted to produce the modulation signal frequency desired For frequencies greater than C 2048 all modulation shapes are sampled up to the maximum modulating frequency A new modulation waveform is computed and loaded into modulation RAM each time the modulation type modulation waveshape or modulation frequency is changed Data in standard arbitrary waveform memory is not affected by modulation signal changes data is expanded or compressed and loaded directly into separate modulation RAM following computation
199. nt Panel Operation Press Shift Level to set the depth in percent the value is displayed for approximately 10 seconds Before setting the modulation depth from the front panel you must have AM enabled If you attempt to set the depth when AM is not enabled SELECT AM FM is displayed Remote Interface Operation AM DEPTh depth in percent MINimum MAXimum 74 Chapter 3 Features and Functions Amplitude Modulation AM Modulating Source The function generator will accept an internal modulating signal an external modulating signal or both Modulating source Internal External both or External only The default is Both internal external The External modulating source is always enabled When both sources are enabled internal external the function generator adds the internal and external modulating signals the carrier waveform is actually modulated with two waveforms When the internal source is disabled external only the carrier waveform is modulated with the external waveform The Ext annunciator turns on to indicate that the function generator is expecting a modulating signal on the rear panel AM Modulation terminal You apply the external modulating waveform to the AM Modulation terminal The modulation depth is controlled by the signal level present 5 volts peak corresponds to 100 modulation AM MODULATION V 5V 1002 OV 5V Front Panel Operation 2 AM SO
200. nt for service 15 Chapter 1 Quick Start If the function generator does not turn on If the function generator does not turn on Use the following steps to help solve problems you might experience when turning on the function generator If you need more help see the Service Guide for instructions on returning the function generator to Agilent for service 1 Verify that there is ac power to the function generator First verify that the function generator s Power switch is in the On position Also make sure that the power cord is firmly plugged into to the power module on the rear panel You should also make sure that the power source you plugged the function generator into is energized 2 Verify the power line voltage setting The line voltage is set to the proper value for your country when the function generator is shipped from the factory Change the voltage setting if it is not correct The settings are 100 120 220 or 240 Vac for 230 Vac operation use the 220 Vac setting See the next page if you need to change the line voltage setting 3 Verify that the power line fuse is good The function generator is shipped from the factory with a 500 mAT fuse installed This is the correct fuse for all line voltages See the next page if you need to change the power line fuse To replace the 500 mAT fuse order Agilent part number 2110 0458 16 Chapter 1 Quick Start If the function generator d
201. o with your function generator is to become acquainted with its front panel We have written the exercises in this chapter to prepare the function generator for use and help you get familiar with some of the front panel operations The front panel has two rows of keys to select various functions and operations Most keys have a shifted function printed in blue above the key To perform a shifted function press Shift the Shift annun ciator will turn on Then press the key that has the desired label above it For example to select the AM amplitude modulation function press Shift AM the shifted version of the v key If you accidentally press Shift just press it again to turn off the Shift annunciator Most keys also have a number printed in green next to the key To enable the number mode press Enter Number the Num annunciator will turn on Then press the keys that have the desired numbers printed next to them For example to select the number 10 press Enter Number 1 0 next to the v and Recall keys If you accidentally press Enter Number just press Shift Cancel to turn off the Num annunciator 14 Chapter 1 Quick Start To prepare the function generator for use To prepare the function generator for use The following steps help you verify that the function generator is ready for use Check the list o
202. odulate the carrier with a sine square triangle ramp noise or arbitrary waveform Use the FM INT FUNC command to select the modulating waveshape Set the modulating frequency Set the modulating frequency to any value between 10 mHz and 10 kHz using the FM INT FREQ command Set the peak frequency deviation Set the deviation to a value between 10 mHz and 7 5 MHz using the FM DEV command Enable FM modulation After you have set up the other modulation parameters use the FM STAT ON command to enable FM 157 Chapter 4 Remote Interface Reference FM Modulation Commands FM Commands Use the APPLy command or the equivalent FUNC SHAP FREQ VOLT and VOLT OFFS commands to configure the carrier waveform Set the carrier frequency between 10 mHz and 15 MHz 100 kHz for triangle and ramp The default is 1 kHz FM DEViation peak deviation in Hz MINimum MAXimum Set the peak frequency deviation in hertz This value represents the variation in frequency of the modulating waveform from the carrier frequency Select from 10 mHz to 7 5 MHz The default is 100 Hz MIN 10 mHz MAX 7 5 MHz Stored in volatile memory The carrier frequency must always be greater than or equal to the peak frequency deviation If you attempt to set the deviation to a value greater than the carrier frequency with FM enabled the function generator will automatically adjust the deviation to equal the present car
203. oes not turn on 1 Remove the power cord Remove the 2 Remove the line voltage selector from fuse holder assembly from the rear panel the assembly UN Fuse 500 mAT for all line voltages Part Number 2110 0458 3 Rotate the line voltage selector until the 4 Replace the fuse holder assembly in correct voltage appears in the window the rear panel 100 120 220 230 or 240 Vac Verify that the correct line voltage is selected and the power line fuse is good 17 18 Chapter 1 Quick Start To adjust the carrying handle To adjust the carrying handle To adjust the position grasp the handle by the sides and pull outward Then rotate the handle to the desired position Pn i MM Bench top viewing positions Carrying position Freq Enter Number 1J 2 l MHz m Vpp In 2 HG Chapter 1 Quick Start To set the output frequency To set the output frequency At power on the function generator outputs a sine wave at 1 kHz with an amplitude of 100 mV peak to peak into a 50Q termination The following steps show you how to change the frequency to 1 2 MHz Enable the frequency modify mode The displayed frequency is either the power on value or the previous frequency selected When you change functions the same frequency is used if the present value is valid for the new function 1
204. of the front panel function keys except Noise For arbitrary waveforms the Arb key selects the waveform that is currently downloaded Remote Interface Operation FUNCtion SHAPe SINusoid SQUare TRIangle RAMP USER You can also use the APPLy command to select the function frequency amplitude and offset with a single command 77 Chapter 3 Features and Functions Frequency Modulation FM Carrier Frequency e Carrier frequency 10 mHz to 15 MHz 100 kHz for triangle and ramp The default is 1 kHz e For arbitrary waveforms the maximum carrier frequency depends on the number of points specified in the waveform The five built in arbitrary waveforms can be output at a maximum of 5 MHz Number of Arb Points Minimum Frequency Maximum Frequency 8 to 8 192 8k 10 mHz 5 MHz 8 193 to 12 287 12k 10 mHz 2 5 MHz 12 288 to 16 000 10 mHz 200 kHz e The carrier frequency must always be greater than or equal to the peak frequency deviation If you attempt to set the carrier frequency to a value less than the deviation the function generator will auto matically adjust the carrier frequency to equal the present deviation From the front panel MIN VALUE is displayed and the carrier frequency is adjusted From the remote interface a 221 Settings conflict error is generated and the carrier frequency is adjusted e The sum of the carrier frequency and peak frequency deviation m
205. ohms Downloading floating point values using DATA VOLATILE is slower than downloading binary values using DATA DAC VOLATILE but is more convenient when using trigonometric functions which return values between 1 and 1 The DATA VOLATILE command overwrites the previous waveform in VOLATILE memory no error is generated Use the DATA COPY command to copy the waveform to non volatile memory Up to four user defined waveforms can be stored in non volatile memory Use the DATA DEL command to delete the waveform in VOLATILE memory or any of the four user defined waveforms in non volatile memory Use the DATA CAT command to list all waveforms currently stored in volatile and non volatile memory and the built in waveforms After downloading the waveform data to memory use the FUNC USER command to choose the active waveform and the FUNC SHAP USER command to output it The following statement shows how to use the DATA VOLATILE command to download nine points to volatile memory DATA VOLATILE 1 75 5 25 0 25 5 75 1 178 Chapter 4 Remote Interface Reference Arbitrary Waveform Commands DATA DAC VOLATILE binary block gt lt value gt value Download binary integer values between 2047 and 2047 into volatile memory You can download between 8 and 16 000 points per waveform in IEEE 488 2 binary block format or as a list of values Th
206. oints for the specified arbitrary waveform The default arb name is the arbitrary waveform currently active selected with FUNC USER command e This command returns a value between 0 and 1 0 with 1 0 indicating full amplitude available 100 e The maximum peak to peak amplitude will be limited if the data points do not span the full range of the output DAC Digital to Analog Converter For example the built in SINC waveform does not use the full range of values between 1 and therefore its maximum peak to peak amplitude is 6 084 Vpp into 50 ohms e Ifyou query a waveform that is not currently stored in memory a 785 Specified arb waveform does not exist error is generated 181 Chapter 4 Remote Interface Reference Arbitrary Waveform Commands DATA CATalog List the names of all waveforms currently downloaded to memory Returns the names of the five built in waveforms non volatile memory VOLATILE if a waveform is currently downloaded to volatile memory and all user defined waveforms downloaded to non volatile memory e Aseries of quoted strings separated with commas is returned SINC NEG RAMP EXP RISE EXP FALL CARDIAC VOLATILE ARB_1 ARB 2 e Use the DATA DEL command to delete the waveform in VOLATILE memory or any of the user defined waveforms in non volatile memory DATA COPY destination arb name gt VOLATILE Copy t
207. ollowing compilers e Microsoft QuickC Version 2 0 e Borland Turbo C Version 1 0 244 Chapter 6 Application Programs C Language Programs Compiling and Linking a C Program To run a program first compile and link the program to make an executable file To compile and link a program e Make sure the necessary PATH statements have been added to your AUTOEXEC BAT file to enable the compiler to find the library and header files see your C Language manual to specify the proper paths e Link the appropriate GPIB C library file for your compiler the file is located on the GPIB Command Library disk that came with the GPIB Interface Card Use the appropriate library file clhpib lib for Microsoft Quick C 9 tchhpib lib for Borland Turbo C 94 e f you are not compiling in the large or huge memory model include the CFUNC H header file in your program the file is located on the GPIB Command Library disk that came with the GPIB Interface Card e To compile Microsoft QuickC programs from the DOS command line using the large memory model execute the following qcl AL path program C gt path Nclhpib lib For example qcl AL b Narb wave c c qc2 lib clhpib lib Change the AL parameter to the appropriate setting when compiling in the smaller memory models see your C Language manual for more information For some programs you may also have to change the stack size using th
208. olon separates a command keyword from a lower level keyword 211 Chapter 4 Remote Interface Reference An Introduction to the SCPI Language Command Format Used in This Manual The format used to show commands in this manual is shown below FREQuency frequency MINimum MAXimum The command syntax shows most commands and some parameters as a mixture of upper and lower case letters The upper case letters indicate the abbreviated spelling for the command For shorter program lines send the abbreviated form For better program readability send the long form For example in the above syntax statement FREQ and FREQUENCY are both acceptable forms You can use upper or lower case letters Therefore FREQUENCY freq and Freq are all acceptable Other forms such as FRE and FREQUEN will generate an error Braces enclose the parameter choices for a given command string The braces are not sent with the command string A vertical bar separates multiple parameter choices for a given command string Triangle brackets lt gt indicate that you must specify a value for the enclosed parameter For example the above syntax statement shows the frequency parameter enclosed in triangle brackets The brackets are not sent with the command string You must specify a value for the parameter such as FREQ 5000 Some parameters are enclosed in square brackets The bra
209. on LANGUAGE Verifies the interface language SCPI F CALibration MENU 1 SECURED 1 UNSECURED gt 2 CALIBRATE gt 3 CAL COUNT 4 MESSAGE 1 1 2 3 4 SECURED The function generator is secured against calibration enter code to unsecure UNSECURED The function generator is unsecured for calibration enter code to secure CALIBRATE Performs individual calibrations must be UNSECURED CAL COUNT Reads the total number of times the function generator has been calibrated MESSAGE Reads the calibration string up to 11 characters entered from remote The commands enclosed in square brackets are hidden unless the function generator is UNSECURED for calibration 32 Chapter 2 Front Panel Menu Operation A front panel menu tutorial A front panel menu tutorial This section is a step by step tutorial which shows you how to use the front panel menu We recommend that you spend a few minutes with this tutorial to get comfortable with the structure and operation of the menu The menu is organized in a top down tree structure with three levels menus commands and parameters You move down lv or up the menu tree to get from one level to the next Each of the three levels has several horizontal choices which you can view by moving left lt or right gt Menus Commands Parameters The menu is organized in a top down tree st
210. on All commands prior to and including an OPC command have been executed Always set to 0 The function generator tried to read the output buffer but it was empty Or a new command line was received before a previous query has been read Or both the input and output buffers are full A self test or calibration error occurred see error numbers 501 through 857 in chapter 5 An execution error occurred see error numbers 211 through 224 in chapter 5 A command syntax error occurred see errors 101 through 168 in chapter 5 Always set to 0 Power has been turned off and on since the last time the event register was read or cleared 207 Chapter 4 Remote Interface Reference The SCPI Status Registers The Standard Event register is cleared when e You execute the CLS clear status command e You query the event register using the ESR event status register command The Standard Event enable register is cleared when e You execute the ESE 0 command e You turn on the power and have previously configured the function generator using the PSC 1 command e The enable register will not be cleared at power on if you have previously configured the function generator using PSC 0 208 Chapter 4 Remote Interface Reference Status Reporting Commands Status Reporting Commands SYSTem ERRor Read one error from the error queue When the front panel ERROR annunciator turns on one or more com
211. on FREQ 5 0E 3 Set frequency to 5 kHz VOLT 3 0 Set amplitude to 3 Vpp VOLT OFFS 2 5 Set offset to 2 5 Vdc 136 Chapter 4 Remote Interface Reference Simplified Programming Overview Reading a Query Response Only the query commands commands that end with will instruct the function generator to send a response message Queries return either output values or internal instrument settings For example the following statements executed from your computer will read the function generator s error queue and print the most recent error dimension statement Dimension string array 80 elements SYST ERR Read error queue bus enter statement Enter error string into computer print statement Print error string Selecting a Trigger Source When burst modulation or frequency sweep is enabled the function generator will accept an immediate internal trigger a hardware trigger from the rear panel Ext Trig terminal or a software bus trigger By default the internal trigger source is selected If you want the function generator to use the external source or a bus trigger you must select that source For example the following statements executed from your computer will output a 3 cycle burst each time the Ext Trig terminal receives the rising edge of a TTL pulse BM NCYC 3 Set burst count to 3 cycles TRIG SOUR EXT Select external trigger source BM STAT ON Enable the burst mode 137 Chapter
212. on X X X X X Burst Modulation X X X X X Frequency Sweep X X X X X FUNCtion SHAPe Query the output function Returns SIN SQU TRI RAMP NOIS DC or USER 145 Chapter 4 Remote Interface Reference Output Configuration Commands FREQuency frequency MINimum MAXimum Set the output frequency MIN selects the lowest frequency allowed for the currently active function MAX selects the highest frequency allowed for the currently active function The default frequency is 1 kHz for all functions Stored in volatile memory Function Minimum Frequency Maximum Frequency Sine 100 uHz 15 MHz Square 100 uHz 15 MHz Ramp 100 Hz 100 kHz Triangle 100 uHz 100 kHz Built In Arbs 1 100 Hz 5 MHz 1 There are five built in arbitrary waveforms stored in non volatile memory sinc negative ramp exponential rise exponential fall and cardiac e For arbitrary waveforms that you create and download to memory the maximum frequency depends on the number of points specified in the waveform As shown below the maximum output frequency decreases as you specify more points in the waveform The five built in arbitrary waveforms can be output at a maximum of 5 MHz Number of Arb Points Minimum Frequency Maximum Frequency 8 to 8 192 8k 100 Hz 5 MHz 8 193 to 12 287 12k 100 Hz 2 5 MHz 12 288 to 16 000 100 Hz 200 kHz e Possible Conflict with Function
213. on generator is unsecured Notice also that the CALIBRATE command is no longer hidden and you can perform a calibration 1 UNSECURED e Remote Interface Operation CALibration SECure STATe OFF ON lt code gt To unsecure the function generator send the above command with the same code used to secure calibration For example CAL SEC STAT OFF HP033120 119 Chapter 3 Features and Functions Calibration Overview To Secure Against Calibration You can secure the function generator against accidental calibration either from the front panel or over the remote interface The function generator is secured when shipped from the factory and the security code is set to HP033120 Be sure to read the security code rules on page 118 before attempting to secure the function generator e Front Panel Operation 1 UNSECURED CAL MENU If the function generator is unsecured you will see the above command when you go into the CAL MENU To secure the function generator go to the PARAMETER level of the UNSECURED command enter the security code and then press Enter A000000 CODE When you go to the COMMANDS level in the CAL MENU again you will notice that the function generator is secured Notice also that the CALIBRATE command is now hidden and you cannot perform a calibration 1 SECURED e Remote Interface Operation CALibration SECure STATe OFF ON lt code gt To secure t
214. on to triangle wave the function generator will adjust the output to 100 kHz the upper limit for triangle waves From the front panel FREQ LIMIT is displayed and the frequency is adjusted From the remote interface a 221 Settings conflict error is generated and the frequency is adjusted Possible Conflict with Duty Cycle square wave only For output frequencies above 5 MHz the duty cycle is limited to values between 40 and 60 below 5 MHz the range is 20 to 80 The duty cycle is automatically adjusted if you select a frequency that is not valid with the present duty cycle For example if you set the duty cycle to 70 and then change the frequency to 8 MHz the function generator will automatically adjust the duty cycle to 60 the upper limit for this frequency From the front panel DUTY LIMIT is displayed and the duty cycle is adjusted From the remote interface a 221 Settings conflict error is generated and the duty cycle is adjusted Front Panel Operation To set the output frequency press Freq Then use the knob arrow keys or Enter Number mode to set the frequency Remote Interface Operation FREQuency lt frequency gt MINimum MAXimum You can also use the APPLy command to select the function frequency amplitude and offset with a single command 58 Chapter 3 Features and Functions Output Configuration Output Amplitude As shown below the output amp
215. ons Comma Separators The function generator can display values on the front panel with or without a comma separator This feature is available only from the front panel 15 000 000 MHz 15 000000 MHz With comma separator Without comma separator factory setting e The display format is stored in non volatile memory and does not change when power has been off or after a remote interface reset The comma separator is enabled when the function generator is shipped from the factory e Front Panel Operation 5 COMMA SYS MENU See also To turn off the comma separator on page 52 Firmware Revision Query The function generator has three microprocessors for control of various internal systems You can query the function generator to determine which revision of firmware is installed for each microprocessor e The function generator returns three numbers The first number is the firmware revision number for the main generator processor the second is for the input output processor and the third is for the front panel processor e Front Panel Operation e Remote Interface Operation IDN Returns HEWLETT PACKARD 33120A 0 X X X X X X Be sure to dimension a string variable with at least 40 characters 113 Chapter 3 Features and Functions Remote Interface Configuration Remote Interface Configuration This section gives information on configuring the remote interface For information on p
216. ons 4 0 and above only e To compile and link a program from the DOS command line is a two step method as follows First compile the program by executing the following bc path program BAS gt This generates an object listing that has the same name as the program name with an OBJ extension The object file must be linked to the GPIB library Second link the GPIB library link path program BAS gt After prompted for a run file press the Enter key This generates the executable file with an EXE extension 247 Chapter 6 Application Programs Using the APPLy Command Using the APPLy Command the GPIB interface BASIC GPIB Program 1 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 This program teaches the following concepts e How to use the APPLy command with low level commands to set up a burst By setting the starting phase to 270 degrees and adding an offset voltage a bursted haversine waveform is generated e How to set up a trigger source and trigger the function generator over This program sets up a burst waveform with a 270 degree starting phase By adding an offset voltage to the burst a haversine is created This program also shows the use of a trigger received over the GPIB interface to initiate a single LEAR 7 SSIGN Fgen TO UTPUT Fgen ora UT Fgen O UT QGFgen A
217. or external trigger When the single or external trigger source is selected the burst count and burst phase remain in effect but the burst rate is ignored When the external gate source is selected gated burst mode the specified trigger source is ignored The external gated mode overrides the triggered mode source Front Panel Operation Pressing Single to enable the single trigger mode also enables the external trigger mode Press Shift Internal to enable the internal trigger mode Remote Interface Operation TRIGger SOURce IMMediate EXTernal BUS See Triggering on page 98 for more information 82 Chapter 3 Features and Functions Burst Modulation Burst Source In the external gated burst mode the output waveform is either on or off based on the level of the external signal applied to the rear panel Ext Trig terminal When the gate signal is true the function generator outputs a continuous waveform When the gate signal is false the output is turned off e Burst source Internal or External Gate The default is Internal e When the internal burst source is selected the external gated mode is disabled e When the external gate source is selected the output is enabled or disabled based on the logic level of the gate signal applied to the Ext Trig terminal When the gate signal is true TTL high the function generator outputs a continuous waveform Whe
218. or for incidental or consequential damages in connection with the furnishing use or performance of this docu ment or any information contain ed herein Should Agilent and the user have a separate written agreement with warranty terms covering the material in this docu ment that conflict with these terms the warranty terms in the separate agreement will control Technologies Licenses The hardware and or software described in this document are furnished under a license and may be used or copied only in accordance with the terms of such license Restricted Rights Legend If software is for use in the perform ance of a U S Government prime contract or subcontract Software is delivered and licensed as Commercial computer software as defined in DFAR 252 227 7014 June 1995 or as a commercial item as defined in FAR 2 101 a or as Restricted computer software as defined in FAR 52 227 19 June 1987 or any equivalent agency regulation or con tract clause Use duplication or disclosure of Software is subject to Agilent Technologies standard commercial license terms and non DOD Departments and Agencies of the U S Government will receive no greater than Restricted Rights as defined in FAR 52 227 19 c 1 2 June 1987 U S Government users will receive no greater than Limited Rights as defined in FAR 52 227 14 June 1987 or DFAR 252 227 7015 b 2 November 1995 as applicable in any technical data
219. or increment each digit independently 00004 CYC 7 Save the change and turn off the menu The function generator beeps and displays a message to show that the change is now in effect You are then exited from the menu ENTERED l You can also use the knob or enter number mode to enter a number See Front Panel Number Entry on page 3 for more information 39 Shift Menu On Off Enter Chapter 2 Front Panel Menu Operation To select the output termination To select the output termination The function generator has a fixed output impedance of 50 ohms on the OUTPUT terminal You can specify whether you are terminating the output into a 500 load or an open circuit Incorrect impedance matching between the source and load will result in an output amplitude or dc offset which does not match the specified value Turn on the menu A MOD MENU Move across to the SYS MENU choice on this level 1 D SYS MENU Move down a level to the OUT TERM command 1 OUT TERM Move down a level and then across to the HIGH Z choice With the output termination set to HIGH Z the function generator allows you to set the unloaded open circuit output voltage Save the change and turn off the menu The function generator beeps and displays a message to show that the change is now in effect You are then exited from the menu You can also use the knob to scroll left or
220. ored in volatile memory The DISP TEXT command is allowed only while the function generator is in the remote mode An error is generated if you attempt to execute the command while in the local mode The following command string shows how to display a message on the front panel DISP TEXT HELLO 188 Chapter 4 Remote Interface Reference System Related Commands DISPlay TEXT Query the message sent to the front panel and return a quoted string For example the query returns a string such as HELLO DISPlay TEXT CLEar Clear the message displayed on the front panel SYSTem BEEPer Issue a single beep immediately SYSTem ERRor Read one error from the error queue When the front panel ERROR annunciator turns on one or more command syntax or hardware errors have been detected record of up to 20 errors can be stored in the function generator s error queue See chapter 5 Error Messages for a complete listing of the errors e Errors are retrieved in first in first out FIFO order The first error returned is the first error that was stored When you have read all errors from the queue the ERROR annunciator turns off The function generator beeps once each time an error is generated e f more than 20 errors have occurred the last error stored in the queue the most recent error is replaced with 350 Too many errors No additional errors are stored until you remove errors from the
221. orm is selected a modulation mode other that burst is enabled or if burst is enabled with a burst count other than infinity Settings conflict duty cycle has been adjusted The requested duty cycle is not valid For output frequencies above 5 MHz the duty cycle is limited to values between 40 and 60 below 5 MHz the range is 20 to 80 The duty cycle is automatically adjusted if you select a frequency that is not valid with the present duty cycle percentage For example if you set the duty cycle to 70 and then change the frequency to 8 MHz the function generator will automatically adjust the duty cycle to 60 the upper limit for this frequency Settings conflict fm deviation has been adjusted The requested FM peak frequency deviation is not valid The sum of the carrier frequency and peak frequency deviation must be less than or equal to the maximum frequency for the selected function plus 100 kHz 15 1 MHz for sine and square 200 kHz for triangle and ramp and 5 1 MHz for arbitrary waveforms If you attempt to set the deviation to a value that is not valid the function generator will automatically adjust the deviation to the maximum value allowed with the present carrier frequency 232 221 221 221 221 Chapter 5 Error Messages Execution Errors Settings conflict frequency has been adjusted The requested output or carrier frequency is not valid The output frequency is automatically adjusted if you s
222. orrectly specified for a numeric parameter You may have misspelled the suffix Example SWE TIME 0 5 SECS Suffix not allowed A suffix was received following a numeric parameter which does not accept a suffix Example BM PHAS 10 DEG this command does not allow a suffix Character data not allowed A discrete parameter was received but a character string or a numeric parameter was expected Check the list of parameters to verify that you have used a valid parameter type Example DISP TEXT ON 230 151 158 161 168 170 211 to 178 Chapter 5 Error Messages Execution Errors Invalid string data An invalid character string was received Check to see if you have enclosed the character string in single or double quotes and that the string contains valid ASCII characters String data not allowed A character string was received but is not allowed for the command Check the list of parameters to verify that you have used a valid parameter type Example BMOD NCYC TEN Invalid block data Applies only to the DATA DAC VOLATILE command For a definite length block the number of bytes of data sent does not match the number of bytes that you specified in the block header For an indefinite length block an EOI End or Identify was received without an accompanying lt new line gt character Block data not allowed Block data was received but is not allowed for th
223. ory This command deletes the waveform in VOLATILE memory and all user defined waveforms in non volatile memory The five built in waveforms in non volatile memory are not deleted e The colon before the ALL parameter is required DATA DELet ALL If you insert a space instead of a colon the function generator will attempt to delete an arbitrary waveform with the name ALL If no such waveform is stored in memory a 785 Specified arb waveform does not exist error is generated e You cannot delete the arbitrary waveform that is currently being output If you attempt to delete the waveform being output a 787 Cannot delete an active arb waveform error is generated e You cannot delete any of the five built in arbitrary waveforms If you attempt to delete one of the built in waveforms a 786 Cannot delete a built in arb waveform error is generated e Use the DATA DEL lt arb name gt command to delete stored waveforms one at a time DATA NVOLatile CATalog List the names of all user defined arbitrary waveforms currently downloaded to non volatile memory Returns the names of up to four waveforms in non volatile memory e A series of quoted strings separated with commas is returned see example below If no user defined waveforms are currently downloaded to non volatile memory the command returns a null string ARB 1 ARB 2 ARB 3 ARB 4 e Use the DATA
224. ote interface reset When switching from remote programming over the interface back to front panel local operation the output units are remembered For example if you select Vrms from the remote interface the units are shown as Vrms on the front panel display Front Panel Operation Use the Enter Number units keys the arrow keys located on the right side of the front panel to select the output units You can also convert from one unit to another from the front panel For example to convert 2 Vpp to its equivalent value in Vrms press the following keys Enter Number v kHz m Vrms The converted value is 707 1 mVrms Remote Interface Operation VOLTage UNIT VPP VRMS DBM DEFault 64 Chapter 3 Features and Functions Output Configuration Output Termination Applies only to output amplitude and offset voltage The function generator has a fixed output impedance of 50 ohms on the OUTPUT terminal You can specify whether you are terminating the output into a 50 ohm load or an open circuit Incorrect impedance matching between the function generator and your load will result in an amplitude or offset which does not match the specified signal level Output termination 500 or High impedance The default is 500 See the table on page 59 for a list of amplitude limits for all functions The output termination setting is stored in volatile memory 500 is selected when power has be
225. ou disable the DTR DSR handshake also select a slower baud rate 300 600 or 1200 baud to ensure that the data is transmitted correctly The function generator sets the DTR line FALSE in the following cases When the function generator s input buffer is full when approximately 100 characters have been received it sets the DTR line FALSE pin 4 on the RS 232 connector When enough characters have been removed to make space in the input buffer the function generator sets the DTR line TRUE unless the second case see below prevents this When the function generator wants to talk over the interface which means that it has processed a query and has received a new line message terminator it will set the DTR line FALSE This implies that once a query has been sent to the function generator the controller should read the response before attempting to send more data It also means that a new line must terminate the command string After the response has been output the function generator sets the DTR line TRUE again unless the first case see above prevents this The function generator monitors the DSR line to determine when the controller is ready to accept data over the interface The function generator monitors the DSR line pin 6 on the RS 232 connector before each character is sent The output is suspended if the DSR line is FALSE When the DSR line goes TRUE transmission will resume 198 Chapter 4 Remote Inte
226. output frequency 19 To set the output amplitude 20 To set a dc offset voltage 21 To set the duty cycle 22 To output a stored arbitrary waveform 23 To output a dc voltage 24 To store the instrument state 25 To rack mount the function generator 27 Chapter 2 Front Panel Menu Operation Front panel menu reference 31 A front panel menu tutorial 33 To select the output termination 40 To output a modulated waveform 41 To output an FSK waveform 44 To output a burst waveform 47 To output a frequency sweep 49 To trigger a burst or sweep 51 To turn off the comma separator 52 U9 U04 Chapter 3 Features and Functions Output Configuration 55 Amplitude Modulation AM 71 Frequency Modulation FM 76 Burst Modulation 81 Frequency Shift Keying FSK Modulation 90 Frequency Sweep 94 Triggering 98 Arbitrary Waveforms 103 System Related Operations 109 Remote Interface Configuration 114 Calibration Overview 118 Power On and Reset State 123 Contents Contents Chapter 4 Remote Interface Reference SCPI Command Summary 127 Simplified Programming Overview 136 Using the APPLy Command 138 Output Configuration Commands 145 AM Modulation Commands 154 FM Modulation Commands 157 Burst Modulation Commands 160 Frequency Shift Keying FSK Commands 167 Frequency Sweep Commands 170 Arbitrary Waveform Commands 174 Triggering 186 System Related Commands 188 Calibration Commands 193 RS 232 Interface Configuration 195 RS 232
227. page oO o Chapter 2 Front Panel Menu Operation To trigger a burst or sweep To trigger a burst or sweep You can issue triggers from the front panel for burst modulation and frequency sweeps using single trigger or internal trigger tg i 33120A x Agilent 15 MHz Function Arbitrery Waveform Generator Internal Internal i KRRRERRRRR h y Adrs Rmt Tri K Burst Swp Enables single trigger and triggers the generator Enables internal trigger Trig annunciator is on when the generator is waiting for single trigger internal trigger disabled e Internal or automatic triggering is enabled when you turn on the function generator In this mode the function generator outputs continuously when burst modulation or sweep is selected e Single triggering outputs one burst or initiates one frequency sweep each time you press Single Continue pressing this key to re trigger the function generator e Pressing Single to enable the single trigger mode also enables the external trigger mode External triggering is like the single trigger mode except that you apply a trigger signal to the rear panel Ext Trig terminal The function generator is triggered on the rising edge of a TTL pulse e The Single key is disabled when in remote the Rmt annunciator turns on when in remote and when a function other than burst modulation or sweep is selected 51 Shift Menu On Off
228. pan the full range of the output DAC Digital to Analog Converter For example the built in SINC waveform does not use the full range of values between 1 and therefore its maximum amplitude is 6 084 Vpp into 50 ohms For arbitrary waveforms the Offset annunciator will turn on if the waveform data has an inherent offset present if the average is not equal to zero The function generator calculates the average of the data points and compares the average to zero volts If the average is not within two DAC Digital to Analog Converter counts of zero volts the Offset annunciator turns on FUNCtion SHAPe Query the output function Returns SIN SQU TRI RAMP NOIS DC or USER 177 Chapter 4 Remote Interface Reference Arbitrary Waveform Commands DATA VOLATILE value value Download floating point values between 1 and 1 into volatile memory You can download between 8 and 16 000 points per waveform The values 1 and 1 correspond to the peak values of the waveform For example if you set the amplitude to 10 Vpp 1 corresponds to 5 volts and 1 corresponds to 5 volts The maximum amplitude will be limited if the data points do not span the full range of the output DAC Digital to Analog Converter For example the built in SINC waveform does not use the full range of values between 1 and therefore its maximum amplitude is 6 084 Vpp into 50
229. pplies only to burst modulation and frequency sweep You can issue triggers for bursts and sweeps using an immediate trigger an external trigger or a bus trigger TRIGger SOURce IMMediate EXTernal BUS Select the source from which the function generator will accept a trigger The function generator will accept an immediate internal trigger a hardware trigger from the rear panel Ext Trig terminal or a software bus trigger The default is Immediate Stored in volatile memory e When the Immediate internal source is selected the function generator outputs continuously when the burst mode or sweep mode is enabled The APPLy command automatically sets the trigger source to IMMediate e When the External source is selected the function generator will accept a hardware trigger applied to the rear panel Ext Trig terminal The function generator outputs one burst or initiates one sweep each time each time Ext Trig receives the rising edge of a TTL pulse The Trig annunciator turns on when the function generator is waiting for an external trigger e When the Bus software source is selected the function generator outputs one burst or initiates one sweep each time a bus trigger command is received To trigger the function generator from the remote interface GPIB or RS 232 send the TRG trigger command You can also trigger the function generator from the GPIB interface by sending the IEEE 488 Group Execute Trigger GET messa
230. press detection of Request to Send rs set timeout of Data Carrier Detect line cd and terminate output with line feed 1f OPEN com2 9600 e 7 2 rs cd lf pe FOR RANDOM AS 1 LEN 1000 PRINT 1 SYST REM Enable the remote RS 232 mode PRINT 1 RST Reset the function generator PRINT 1 FORM BORD SWAP Swap data bytes send LSB first PRINT 1 FREQ 5000 Output frequency is 5 kHz PRINT 1 OUTP LOAD 50 Output termination is 50 ohms PRINT 1 VOLT 5 Output amplitude is 5 Vpp 268 Chapter 6 Application Programs Downloading an Arbitrary Waveform over RS 232 continued Calculate data points PRINT Calculating Data Points pi 3 1415 FOR I 1 TO npnts waveform I EXP DAMPFACTOR I npnts SIN 2 pi NCYCLES I npnts NEXT I Download data points to volatile memory PRINT Downloading Arb PRINT 1 DATA VOLATILE FOR I 1 TOnpnts 1 PRINT 1 STR waveform I NEXT I PRINT 1 STRS waveform npnts PRINT 1 OPC Wait for download to complete INE INPUT 1 resp PRINT Download Complete PRINT 1 DATA COPY DAMP SIN VOLATILE Copy to non volatile memory PRINT 1 FUNC USER DAMP SIN Select the active arb PRINT 1 FUNC SHAP USER Output the selected arb PRINT 1 OPC LINE INPUT 1 resp PRINT Program Complete Ez ND End of Program
231. quency is 200 Hz CALL IOOUTPUTS Dev amp Infol Length1 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR Infol1 AM DEPT 80 Length1 LEN Info1 CALL IOOUTPUTS Modulating depth is 80 Dev amp Infol1 Length1 IF PCIB ERR NOERR THEN ERROR PCIB BASERR Infol1 AM STAT ON Length1 LEN Info1 CALL IOOUTPUTS Dev amp Infol Turn AM modulation on Length1 IF PCIB ERR lt gt NOERR THEN ERROR PCIB BASERR Infol1 SAV 1 Length1 LEN Info1 CALL IOOUTPUTS Dev amp Infol Store state in memory location 1 Length1 IF PCIB ERR NOERR THEN ERROR PCIB BASERR Use the RCL 1 command to recall the stored state End of Program 2 254 Chapter 6 Application Programs Downloading an Arbitrary Waveform over GPIB Downloading an Arbitrary Waveform over GPIB BASIC GPIB Program 3 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 This program teaches the following concepts e How to define a set of waveform points over the GPIB interface and download the points to volatile memory The downloaded waveform is a square wave pulse 4 000 points with a calculated rise and fall time e How to copy the download waveform to non volatile me
232. r that is to say the sine wave frequencies are integer multiples of the lowest or fundamental frequency of the waveform Unlike dc signals the amplitude of ac waveforms varies with time as shown in the following figure V pk V rms V avg V pk pk f A sine wave can be uniquely described by any of the parameters indicated the peak to peak value peak value or RMS value and its period T or frequency 1 T 288 AC Attributes continued Chapter 7 Tutorial Attributes of AC Signals The magnitude of a sine wave can be described by the RMS value effective heating value the peak to peak value 2 x zero to peak or the average value Each value conveys information about the sine wave The table below shows several common waveforms with their respective peak and RMS values Waveform Shape Crest Factor C F AC RMS AC DC RMS d EN V 1414 2 xd NL 1732 m oz EU VE ea e Qo 2 t C F C F C F t Each waveshape exhibits a zero to peak value of V volts Crest factor refers to the ratio of the peak to RMS value of the waveform 284 Chapter 7 Tutorial Attributes of AC Signals RMS The RMS value is the only measured amplitude characteristic of a waveform that does not depend on waveshape Therefore the RMS value is the most useful way to specify ac signal amplitudes The RMS value or equivalent heating value specifies the ability of the ac
233. r For example you can store such information as the last calibration date the next calibration due date the instrument serial number or even the name and phone number of the person to contact for a new calibration Stored in non volatile memory e You can record information in the calibration message only from the remote interface However you can read the message from either the front panel menu or the remote interface e The calibration message may contain up to 40 characters However the function generator can display only 11 characters of the message on the front panel additional characters are truncated CALibration STRing Query the calibration message and return a quoted string CALibration VALue value Specify the value of the known calibration signal used by the calibration procedure Use the CAL SET command to configure the function generator s internal state for each of the calibration steps to be performed CALibration VALue Query the present calibration value 194 Chapter 4 Remote Interface Reference RS 232 Interface Configuration RS 232 Interface Configuration See also Remote Interface Configuration on page 114 in chapter 3 You connect the function generator to the RS 232 interface using the 9 pin DB 9 serial connector on the rear panel The function generator is configured as a DTE Data Terminal Equipment device For all communications over the RS 232 interface the function
234. r by applying a trigger signal to the rear panel Ext Trig terminal At power on the internally triggered burst mode is enabled External Gated Burst Mode In this mode the output waveform is either on or off based on the level of the external signal applied to the rear panel Ext Trig terminal When the gate signal is true the function generator outputs a continuous waveform When the gate signal is false the output is turned off Trigger Source Burst Source Burst Count Burst Rate Burst Phase TRIG SOUR BM SOUR BM NCYC BM INT RATE BM PHAS External Triggered Mode External Internal Available Not Used Available Internal Triggered Mode Internal Internal Available Available Available External Gated Mode Internal External Not Used Not Used Not Used 160 Chapter 4 Remote Interface Reference Burst Modulation Commands Set up the burst carrier waveform Use the APPLy command or the equivalent FUNC SHAP FREQ VOLT and VOLT OFFS commands to select the function frequency amplitude and offset of the carrier waveform You can select a sine square triangle ramp or arbitrary waveform for the carrier Set the burst count Set the burst count number of cycles per burst to any value between 1 and 50 000 cycles using the BM NCYC command Used only in the triggered burst mode internal or external source Set the burst rate Set the burst rate the frequency at which internally triggere
235. r example if you set the start frequency to 200 kHz in the sine wave function and then change the function to triangle wave the function generator will adjust the output to 100 kHz the upper limit for triangle waves 233 221 221 222 222 222 222 223 Chapter 5 Error Messages Execution Errors Settings conflict stop frequency has been adjusted The requested stop frequency is not valid The stop frequency is automatically adjusted if you select a function whose maximum frequency is less than that of the currently active function For example if you set the stop frequency to 1 MHz in the sine wave function and then change the function to triangle wave the function generator will adjust the output to 100 kHz the upper limit for triangle waves Settings conflict previous modulation has been disabled Only one modulation state can be enabled at a time When you enable a modulation state the previous modulation state is turned off For example if AM is on and then you enable FM the function generator will turn off AM first Data out of range A numeric parameter value is outside the valid range for the command Example BMOD NCYC 3 or FREQ 16 MHZ Data out of range amplitude The requested output amplitude exceeds the upper limit for the selected function This error applies only to the APPLy command See Output Amplitude on page 59 for more information Data out of range frequency The r
236. r logarithmically spaced based on the sweep mode setting Like FSK modulation described on the next page the sweep function is also a special case of frequency modulation FM All of the FM operations described on the previous page also apply to sweep when the following translations are applied Start Frequency Stop Frequency 2 Carrier Frequency Start Frequency Stop Frequency 2 Deviation The modulation waveshape for sweeps is a ramp wave or exponential wave for linear or log sweeps respectively The logic sense of the ramp or exponential modulation signal positive or negative ramp is selected when the stop frequency is either larger or smaller than the start frequency Like the FM function changes to sweep parameters cause the generator to automatically compute a modulation signal and download it into modulation RAM Similarly the sweep time parameter adjusts the period of the modulating waveform The sweep function also allows triggered operation This is like frequency modulating with a single cycle burst of the modulating signal beginning when a trigger is received Trigger signals can come from the rear panel Ext Trig terminal the front panel Single button or from commands over the remote interface A sine wave sweep from 50 Hz to 5 kHz with a linear 1 second sweep time 289 Chapter 7 Tutorial Modulation Frequency Shift Key Modulation In Frequency Shift Keying modulation FSK
237. rary waveforms The following names are reserved and cannot be deleted with the DATA DEL command SINC NEG_RAMP EXP_RISE EXP_FALL and CARDIAC Cannot delete the currently selected active arb waveform You cannot delete the arbitrary waveform that is currently being output Either select a different arbitrary waveform or change to a different output function Cannot copy to VOLATILE arb waveform The DATA COPY command copies the arbitrary waveform from volatile memory to the specified name in non volatile memory The source for the copy operation is always VOLATILE you cannot copy from any other name and you cannot copy to VOLATILE Arb waveform must contain at least 8 points You cannot create an arbitrary waveform with fewer than 8 data points Redefine the waveform with between 8 and 16 000 data points Block length must be even The function generator represents binary data as a 12 bit integers which is sent as two bytes DATA DAC VOLATILE command only An odd number of bytes is not accepted because the function generator would not know how to interpret the last single byte State has not been stored The memory location specified in the RCL command was not used in a previous SAV command You cannot recall the instrument state from a memory location that was not previously specified as a storage location 241 242 Application Programs Application Programs This chapter
238. requency of the carrier signal In the external gated mode the carrier frequency is output when the external gate signal is true TTL high Keep in mind that the carrier frequency is different than the burst rate which specifies the interval between bursts triggered mode only e Carrier frequency 10 mHz to 5 MHz 100 kHz for triangle and ramp The default is 1 kHz You can use sine square ramp triangle or arbitrary waveforms for the carrier waveshape e Be sure to note the restrictions for carrier frequency and burst count shown on the following pages 84 Chapter 3 Features and Functions Burst Modulation e For arbitrary waveforms used as the carrier waveform the maximum frequency depends on the number of points specified in the waveform The five built in arbitrary waveforms can be output at a maximum of 5 MHz be sure to note the restrictions below Number of Arb Points 8 to 8 192 8k 8 193 to 12 287 12k 12 288 to 16 000 Minimum Frequency Maximum Frequency 10 mHz 5 MHz 10 mHz 2 5 MHz 10 mHz 200 kHz e For sine square and arbitrary waveforms does not apply to ramp and triangle waveforms the relationship between the carrier frequency and the minimum burst count is shown below Carrier Frequency 10 mHz to 1 MHz gt 1 MHz to 2 MHz gt 2 MHz to 3 MHz gt 3 MHz to 4 MHz gt 4 MHz to 5 MHz Minimum Burst Count ocv For sine square and arbitrary wave
239. rface Reference RS 232 Interface Configuration The function generator holds the DTR line FALSE while output is suspended A form of interface deadlock exists until the controller asserts the DSR line TRUE to allow the function generator to complete the transmission You can break the interface deadlock by sending the Ctrl C character which clears the operation in progress and discards pending output this is equivalent to the IEEE 488 device clear action For the Ctrl C character to be recognized reliably by the function generator while it holds DTR FALSE the controller must first set DSR FALSE When downloading binary data for an arbitrary waveform press the front panel LOCAL key first and then send lt Ctrl C gt RS 232 Troubleshooting Here are a few things to check if you are having problems communicating over the RS 232 interface If you need additional help refer to the documentation that came with your computer e Verify that the function generator and your computer are configured for the same baud rate parity and number of data bits Make sure that your computer is set up for 1 start bit and 2 stop bits these values are fixed on the function generator e Make sure to execute the SYSTEM REMOTE command to place the function generator in the REMOTE mode e Verify that you have connected the correct interface cable and adapters Even if the cable has the proper connectors for your system the intern
240. riangle waveform function is enabled al Ramp waveform function is enabled To review the display annunciators hold down the Shift key as you turn on the function generator The Rear Panel at a Glance il a Ext Trig Modulation FSK Buret j vline 45 440 Hz BOVA Max RO 100v dd p 5V 100 v emo E es Fuse 2 ONAT o OC 9 eje d ii i de Chassis ground 5 External Trigger FSK Burst modulation Power line fuse holder assembly input terminal Power line voltage setting GPIB IEEE 488 interface connector AM modulation input terminal RS 232 interface connector koOND NO Use the front panel Input Output Menu to e Select the GPIB or RS 232 interface see chapter 4 e Set the GPIB bus address see chapter 4 e Set the RS 232 baud rate and parity see chapter 4 In This Book Quick Start Chapter 1 prepares the function generator for use and helps you get familiar with a few of its front panel features Front Panel Menu Operation Chapter 2 introduces you to the front panel menu and describes some of the function generator s menu features Features and Functions Chapter 3 gives a detailed description of the function generator s capabilities and operation You will f
241. rier frequency From the remote interface a 221 Settings conflict error is generated and the deviation is adjusted The sum of the carrier frequency and peak frequency deviation must be less than or equal to the maximum frequency for the selected function plus 100 kHz 15 1 MHz for sine and square 200 kHz for triangle and ramp and 5 1 MHz for arbitrary waveforms If you attempt to set the deviation to a value that is not valid the function generator will automatically adjust the deviation to the maximum value allowed with the present carrier frequency From the remote interface a 221 Settings conflict error is generated and the deviation is adjusted FM DEViation MINimum MAXimum Query the peak frequency deviation Returns a value in hertz 158 Chapter 4 Remote Interface Reference FM Modulation Commands FM INTernal FUNCtion SINusoid SQUare TRIangle RAMP NOISe USER Select the shape of the modulating waveform You can use the noise function as the modulating waveform However you cannot use the noise function or dc volts as the carrier waveform The default is SIN Stored in volatile memory FM INTernal FUNCtion Query the shape of the modulating waveform Returns SIN SQU TRI RAMP NOIS or USER FM INTernal FREQuency lt requency gt MINimum MAXimum Set the frequency of the modulating waveform Select from 10 mHz to 10 kHz The default is 10 Hz MIN 10
242. rogramming the function generator over the remote interface see chapter 4 Remote Interface Reference starting on page 125 GPIB Address Each device on the GPIB IEEE 488 interface must have a unique address You can set the function generator s address to any value between 0 and 30 The current address is displayed momentarily on the front panel when you turn on the function generator The address is set to 10 when the function generator is shipped from the factory The GPIB address can be set from the front panel only e The address is stored in non volatile memory and does not change when power has been off or after a remote interface reset e Your GPIB bus controller has its own address Be sure to avoid using the bus controller s address for any instrument on the interface bus Agilent controllers generally use address 21 e Front Panel Operation 1 HPIB ADDR I O MENU See also To set the GPIB address on page 217 114 Chapter 3 Features and Functions Remote Interface Configuration Remote Interface Selection The function generator is shipped with both an GPIB IEEE 488 interface and an RS 232 interface Only one interface can be enabled at a time The GPIB interface is selected when the function generator is shipped from the factory The remote interface can be selected from the front panel only e The interface selection is stored in non volatile memory and doe
243. rror is generated Use the DATA DEL command to delete the waveform in VOLATILE memory or any of the four user defined waveforms in non volatile memory Use the DATA CAT command to list all waveforms currently stored in volatile and non volatile memory e The following statement shows how to use the DATA COPY command DATA COPY ARB_1 VOLATILE DATA DELete lt arb name gt Delete the specified arbitrary waveform from memory You can delete the waveform in volatile memory or any of the four user defined waveforms in non volatile memory e You cannot delete the arbitrary waveform that is currently being output If you attempt to delete the waveform being output a 787 Cannot delete an active arb waveform error is generated e You cannot delete any of the five built in arbitrary waveforms If you attempt to delete one of the built in waveforms a 786 Cannot delete a built in arb waveform error is generated e Use the DATA DEL ALL command to delete the waveform in VOLATILE memory and all user defined non volatile waveforms all at once If one of the waveforms is currently being output a 787 Cannot delete an active arb waveform error is generated The active waveform is not deleted but all of the other waveforms are deleted 183 Chapter 4 Remote Interface Reference Arbitrary Waveform Commands DATA DELete ALL Delete all user defined arbitrary waveforms from mem
244. rst character must always be a letter A 12 characters e To secure the function generator from the remote interface so that it can be unsecured from the front panel use the eight character format shown below The first two characters must be HP and the remaining characters must be numbers Only the last six characters are recognized from the front panel but all eight characters are required To unsecure the function generator from the front panel omit the HP and enter the remaining characters as shown on the following pages H P 8 characters 118 Chapter 3 Features and Functions Calibration Overview To Unsecure for Calibration You can unsecure the function generator for calibration either from the front panel or over the remote interface The function generator is secured when shipped from the factory and the security code is set to HP033 120 e Front Panel Operation 1 SECURED CAL MENU If the function generator is secured you will see the above command when you go into the CAL MENU If you move across the COMMANDS level in the menu you will notice that the CALIBRATE command is hidden when the function generator is secured To unsecure the function generator go to the PARAMETER level of the SECURED command enter the security code and then press Enter A000000 CODE When you go to the COMMANDS level in the CAL MENU again you will notice that the functi
245. rting on page 90 e Frequency Sweep starting on page 94 e Triggering starting on page 98 e Arbitrary Waveforms starting on page 103 e System Related Operations starting on page 109 e Remote Interface Configuration starting on page 114 e Calibration Overview starting on page 118 e Power On and Reset State on page 123 Some knowledge of the front panel menu will be helpful before you read this chapter If you have not already read chapter 2 Front Panel Menu Operation starting on page 29 you may want to read it now Chapter 4 Remote Interface Reference starting on page 125 lists the syntax for the SCPI commands available to program the function generator Throughout this manual the following conventions are used for SCPI command syntax for remote interface programming e Square brackets indicate optional keywords or parameters e Braces enclose parameters within a command string e Triangle brackets lt gt indicate that you must substitute a value for the enclosed parameter e A vertical bar separates multiple parameter choices 54 Chapter 3 Features and Functions Output Configuration Output Configuration This section contains information to help you configure the function generator for outputting waveforms You may never have to change some of the parameters discussed here but they are provided to give you the flexibility you might need Output Function The function
246. ructure with three levels e To turn on the menu press Shift Menu On Off e To turn off the menu press Shift Menu On Off e To execute a menu command press Enter e To recall the last menu command that was executed press Shift Recall Menu e To turn off the menu at any time without saving changes press Shift Cancel 33 Chapter 2 Front Panel Menu Operation A front panel menu tutorial Messages Displayed During Menu Use TOP OF MENU You pressed while on the MENUS level this is the top level of the menu and you cannot go any higher To turn off the menu press Shift Menu On Off To move across the choices on a level press lt Or To move down a level press v MENUS You are on the MENUS level Press lt or gt to view the choices COMMANDS You are on the COMMANDS level Press lt or gt to view the command choices within the selected menu group PARAMETER You are on the PARAMETER level Press lt or gt to view and edit the parameter for the selected command MENU BOTTOM You pressed v while on the PARAMETER level this is the bottom level of the menu and you cannot go any lower To turn off the menu press Shift Menu On Off To move up a level press ENTERED The chang
247. s 410 OUTPUT Fgen FREQ 5000 VOLT 5 Output frequency is 5 kHz 5 Vpp 420 430 END C GPIB Program 3 J ECECKCKCkCkkkckckockockockockockocko oko ko kk kckckckckckckckokockockockokckckckck ck ck ck ck ck ck ck ck ck ok kkk kkk kk ck ck ck ck ck kk kkk kkk k kkk k k This program uses the arbitrary waveform function to download and output a square wave pulse with a calculated rise time and fall time The waveform consists of 4000 points downloaded over the GPIB interface as ASCII data eR RR RR ck ck ck ck ck ck ck ck ckokokokckckckck ck ck ck ck ck ck ck ck ok ck ok oko ko ke ke ke ke ke ke ke J include lt stdio h gt Used for printf include lt stdlib h gt Used for malloc free atoi include lt string h gt Used for strlen include lt cfunc h gt Header file from GPIB Command Library define ISC 7L Assign GPIB select code define ADDR 710L Set GPIB address for function generator Function Prototypes void rst_clear void void get data void void download data float waveform int num points void out waveform void void command exe char commands int length void check error char func name BK RR RK kk RRR KR RK ko kk RR KKK KR kk kc kckck ck ck ck ck ck ck ckckckckckckckckck ck ck ck ck ck ck ck ck ck ok ck oko ko ko ke ke ke ke ke ke 256 Chapter 6 Application Programs Downloading an Arbitrary Waveform over GPIB continued void
248. s been off or after a remote interface reset e Front Panel Operation 3 BAUD RATE I O MENU See also To set the baud rate on page 219 Parity Selection RS 232 You can select the parity for RS 232 operation The function generator is configured for no parity and 8 data bits when shipped from the factory The parity can be set from the front panel only e Select one of the following None 8 data bits Even 7 data bits or Odd 7 data bits When you set the parity you are indirectly setting the number of data bits e The parity selection is stored in non volatile memory and does not change when power has been off or after a remote interface reset e To download binary data for arbitrary waveforms over the RS 232 interface you must select 8 data bits with no parity e Front Panel Operation 4 PARITY I O MENU See also To set the parity on page 220 116 Chapter 3 Features and Functions Remote Interface Configuration Programming Language Query The function generator complies with the rules and conventions of the present version of SCPI Standard Commands for Programmable Instruments You can verify from the front panel that the SCPI language is selected The interface language can be queried from the front panel only e Front Panel Operation 5 LANGUAGE I O MENU SCPI Language Version Query You can determine the SCPI version with which the function generator is in comp
249. s not change when power has been off or after a remote interface reset e Ifyou select the GPIB interface you must select a unique address for the function generator The current address is displayed momentarily on the front panel when you turn on the function generator e Your GPIB bus controller has its own address Be sure to avoid using the bus controller s address for any instrument on the interface bus e Ifyou enable the RS 232 interface you must select the baud rate and parity to be used RS 232 is displayed momentarily on the front panel when you turn on the function generator if you have selected this interface e Front Panel Operation 2 INTERFACE I O MENU See also To select the remote interface on page 218 Refer to RS 232 Interface Configuration starting on page 195 for more information on connecting the function generator to a computer terminal or modem over the RS 232 interface 115 Chapter 3 Features and Functions Remote Interface Configuration Baud Rate Selection RS 232 You can select one of six baud rates for RS 232 operation The rate is set to 9600 baud when the function generator is shipped from the factory The baud rate can be set from the front panel only e Select one of the following 300 600 1200 2400 4800 or 9600 baud The factory setting is 9600 baud e The baud rate selection is stored in non volatile memory and does not change when power ha
250. s once each time an error is generated e Ifmore than 20 errors have occurred the last error stored in the queue the most recent error is replaced with 350 Too many errors No additional errors are stored until you remove errors from the queue If no errors have occurred when you read the error queue the function generator responds with 0 No error e The error queue is cleared when power has been off or after a CLS clear status command has been executed The RST reset command does not clear the error queue e Front Panel Operation 3 ERROR SYS MENU If the ERROR annunciator is on press Shift lt Recall Menu to read the errors stored in the queue The errors are listed horizontally on the PARAMETER level All errors are cleared when you go to the PARAMETER level and then turn off the menu First error in queue Error code e Remote Interface Operation SYSTem ERRor Reads one error from the error queue Errors have the following format the error string may contain up to 80 characters 113 Undefined header 110 Chapter 3 Features and Functions System Related Operations Self Test A power on self test occurs automatically when you turn on the function generator This limited test assures you that the function generator is operational A complete self test runs a series of tests and takes approximately 10 seconds to execute If al
251. s the number of points in a new arb waveform 8 to 16 000 points Performs a linear interpolation between two points in the arb waveform Edits the individual points of the selected arb waveform Inverts the selected arb waveform by changing the sign of each point Saves the current arb waveform in non volatile memory Deletes the selected arb waveform from non volatile memory The commands enclosed in square brackets are hidden until you make a selection from the NEW ARB command to initiate a new edit session 31 Chapter 2 Front Panel Menu Operation Front panel menu reference D SYStem MENU 1 OUT TERM gt 2 POWER ON 3 ERROR gt 4 TEST gt 5 COMMA 6 REVISION D BO NE OUT TERM Selects the output termination 509 or high impedance POWER ON Enables or disables automatic recall of the power down state ERROR Retrieves errors from the error queue up to 20 errors TEST Performs a complete self test COMMA Enables or disables a comma separator between digits on the display REVISION Displays the function generator s firmware revision codes E Input Output MENU 1 HPIB ADDR amp 2 INTERFACE 3 BAUD RATE 4 PARITY amp 5 LANGUAGE akhond HPIB ADDR Sets the GPIB bus address 0 to 30 INTERFACE Selects the GPIB or RS 232 interface BAUD RATE Selects the baud rate for RS 232 operation PARITY Selects even odd or no parity for RS 232 operati
252. sed at power on CAT Il 50 VA peak 28 W average O C to 55 C 80 Relative Humidity to 40 C Indoor or sheltered location 40 C to 70 C Power off state automatically saved Three 3 User Configurable Stored States Arbitrary waveforms stored separately 254 4 mm x 103 6 mm x 374 mm 212 6 mm x 88 5 mm x 348 3 mm 4 kg 8 8 lbs 1 For 400 Hz operation at 120 Vac use the 100 Vac line voltage setting Safety Designed to EMC Vibration and Shock Acoustic Noise Warm Up Time Warranty Remote Interface Programming Language Accessories Included EN61010 CSA1010 UL 1244 EN61326 1 1997 1A 1998 MIL T 28800E Type III Class 5 data on file 30 dBa 1 hour 3 years standard IEEE 488 and RS 232 standard SCPI 1993 IEEE 488 2 User s Guide Service Guide Quick Reference Card IntuiLink Arb software RS 232 cable Test Report and power cord 300 Chapter 8 Specifications Agilent 33120A Function Generator PRODUCT DIMENSIONS ui s SEHE 103 6 mm C MU oo00r00 g 254 4 mm EN me NM m 374 0 mm ogBaoonous O ncaoaoocooo8 Q9 z 216 6 mm 4 2X 552 S0 m 348 3 mm M4 X 0 7 4 PLACES 19 68 l i
253. selected gated burst mode the burst count burst rate burst phase and burst trigger source are ignored these parameters are used for the triggered burst mode only Front Panel Operation 6 BURST PHAS MOD MENU Remote Interface Operation BM PHASe lt degrees gt MINimum MAXimum 89 Chapter 3 Features and Functions Frequency Shift Keying FSK Modulation Frequency Shift Keying FSK Modulation You can configure the function generator to shift its output frequency between two preset values using FSK modulation The rate at which the output shifts between the two frequencies called the carrier frequency and the hop frequency is determined by the internal rate generator or the signal level on the rear panel FSK terminal The function generator can produce an FSK waveform using sine square triangle ramp and arbitrary waveforms For more information on the fundamentals of FSK Modulation refer to chapter 7 Tutorial To Select FSK Modulation e The FSK annunciator turns on when FSK is enabled e Only one modulation mode can be enabled at a time When you enable FSK the previous modulation mode is turned off e Front Panel Operation Enable FSK before you set up the other modulation parameters Press Shift FSK to output the waveform using the present settings for frequency amplitude and offset voltage e Remote Interface Operation To ensure proper opera
254. selection 145 output termination load front panel selection 40 65 remote interface selection 65 151 schematic diagram 281 output units front panel selection 64 remote interface selection 150 overview front panel 2 menu structure 4 product 1 rear panel 6 P parameter types SCPI 215 parity RS 232 arb waveform limits 116 195 choices 116 195 factory setting 116 195 selecting 220 peak deviation FM 80 158 peak to peak value 181 285 peak value 285 percent modulation See modulation depth percentage AM depth 155 duty cycle 147 phase burst 89 163 phase lock Option 001 See Option 001 User s Service Guide 306 Index points number in arb waveform 181 ports serial COM 199 power down recall 109 152 power line voltage fuse 16 selecting 16 power on state 123 printing history inside front cover product dimensions 301 product overview 1 programming examples 243 269 overview 136 SCPI introduction 211 215 PULS DCYC command 147 pulse example program 255 Q query commands 214 query reading 137 quick start 13 QuickBASIC examples 247 QuickC examples 244 R rack mounting kits 27 rear panel Ext Trig FSK Burst terminal 102 overview 6 recall menu 33 37 recall state front panel operation 26 remote interface operation 153 register diagram status 202 remote interface command reference 125 225 command summary 127 135 programming over
255. sending the Ctrl C character will perform the same operation as the IEEE 488 device clear message The function generators DTR data terminal ready handshake line is set true following a device clear message See DTR DSR Handshake Protocol on page 198 for further details 216 Shift Menu On Off Enter Chapter 4 Remote Interface Reference To set the GPIB address To set the GPIB address Each device on the GPIB IEEE 488 interface must have a unique address You can set the function generator s address to any value between 0 and 30 The address is set to 10 when the function generator is shipped from the factory The current address is displayed momentarily on the front panel when you turn on the function generator See also GPIB Address on page 114 Turn on the menu A MOD MENU Move across to the I O MENU choice on this level E I O MENU Move down a level to the HPIB ADDR command Move down to the PARAMETER level to set the address Use the left right and down up arrow keys to change the address 10 ADDR Save the change and turn off the menu The address is stored in non volatile memory and does not change when power has been off or after a remote interface reset 217 Shift Menu On Off Enter Chapter 4 Remote Interface Reference To select the remote interface To se
256. set duty cycle as well as any modulation parameters To recall a stored state you must use the same memory location used previously to store the state e You cannot recall the instrument state from a memory location that was not previously specified as a storage location For example an error is generated if you attempt to recall from memory location 2 but have never stored to that location From the front panel NOT STORED is displayed if nothing is stored in the specified memory location From the remote interface a 810 State has not been stored error is generated if nothing is stored in the specified memory location e Any arbitrary waveforms downloaded to VOLATILE memory are not remembered However if an arbitrary waveform is being output from non volatile memory when the state is stored the waveform data is stored The stored waveform is output when the instrument state is recalled e Ifyou delete an arbitrary waveform after storing the state the waveform data is lost and the function generator will not output the waveform when the state is recalled The SINC waveform is output in place of the deleted waveform 69 State Storage continued Chapter 3 Features and Functions Output Configuration When power is turned off the function generator automatically stores its state in memory location 0 You can configure the function generator to automatically recall the power down state
257. shown in bold 129 Chapter 4 Remote Interface Reference SCPI Command Summary Frequency Shift Keying FSK Commands see page 167 for more information SOURce FSKey FREQuency lt frequency gt MINimum MAXimum FSKey FREQuency MINimum MAXimum FSKey INTernal RATE rate in Hz MINimum MAXimum FSKey INTernal RATE MINimum MAXimum FSKey SOURce INTernal EXxTernal FSKey SOURCe FSKey STATe OFF ON FSKey STATe Sweep Commands see page 170 for more information SOURce FREQuency S1 FREQuency S1 FREQuency S1 FREQuency S1 SOURce TARt lt frequency gt MINimum MAXimum CARE MINimum MAXimum TOP lt frequency gt MINimum MAXimum TOP MINimum MAXimum SWEep SPACing LINear LOGarithmic SWEep SPACing SWEep TIME lt seconds gt MINimum MAXimum SWEep TIME SWEep STATe MINimum MAXimum OFF ON SWEep STATe TRIGger SOURce IMMediate ExTernal BUS Triggered Sweep Mode TRIGger SOURCe Default paramete rs are shown in bold 130 Chapter 4 Remote Interface Reference SCPI Command Summary Arbitrary Waveform Commands see page 174 for more information SOURce FUNCtion USER lt arb name VOLATILE FUNCtion USER FUNCtion SHAPe USER FUNCtion SHAPe 1 Specify 1 of the 5 built in waveforms or a user defined waveform name DATA VOLATILE lt value gt lt val
258. signal to deliver power to a resistive load heat The RMS value is equal to the dc value which produces the same amount of heat as the ac waveform when connected to the same resistive load For a dc voltage this heat is directly proportional to the amount of power dissipated in the resistance For an ac voltage the heat in a resistive load is proportional to the average of the instantaneous power dissipated in the resistance This has meaning only for periodic signals The RMS value of a periodic waveform can be obtained by taking the dc values at each point along one complete cycle squaring the values at each point finding the average value of the squared terms and taking the square root of the average value This method leads to the RMS value of the waveform regardless of the signal shape Peak to Peak and Peak Value The zero to peak value is the maximum positive voltage of a waveform Likewise the peak to peak value is the magnitude of the voltage from the maximum positive voltage to the most negative voltage peak The peak or peak to peak amplitude of a complex ac waveform does not necessarily correlate to the RMS heating value of the signal When the specific waveform is known you can apply a correction factor to convert peak or peak to peak values to the correct RMS value for the waveform Average Value The average value of an ac waveform is the average of the instantaneous values measured over one complete cycle For sine waves
259. specify frequency to use the amplitude parameter and you must specify both frequency and amplitude to use the offset parameter The following statement is valid frequency and amplitude are specified offset is omitted APPL SIN 5 0E 3 3 0 However you CANNOT specify amplitude and offset without frequency e You can substitute MINimum MAXimum or DEFault in place of specific values for the frequency amplitude and offset parameters For example the following statement outputs a 3 Vpp sine wave at 15 MHz the maximum frequency for sine with a 2 5 volt offset APPL SIN MAX 3 0 2 5 APPLy SINusoid frequency lt amplitude gt lt offset gt Output a sine wave with the specified frequency amplitude and dc offset The waveform is output as soon as the command is executed APPLy SQUare lt frequency gt lt amplitude gt lt offset gt Output a square wave with the specified frequency amplitude and dc offset The waveform is output as soon as the command is executed APPLy TRIangle frequency lt amplitude gt lt offset gt 1 Output a triangle wave with the specified frequency amplitude and dc offset The waveform is output as soon as the command is executed APPLy RAMP frequency lt amplitude gt lt offset gt 11 Output a ramp wave with the specified frequency amplitude and dc offset The waveform is output as soon as the command is executed 1
260. state see Power On and Reset State on page 123 independent of the POWER ON command setting in the front panel SYS MENU In the sweep mode the RST command does not set the start and stop frequencies to their default values Instead the reset operation sets the start frequency to 10 mHz minimum and the stop frequency to 15 MHz maximum TST Perform a complete self test of the function generator Returns 0 if the self test passes or 1 if it fails If the self test fails an error message is also generated with additional information on why the test failed 190 Chapter 4 Remote Interface Reference System Related Commands sav 0 1 2 3 Store up to four different instrument configurations Stored in non volatile memory Four memory locations numbered 0 1 2 and 3 are available to store instrument configurations The state storage feature remembers the function including arbitrary waveforms frequency amplitude dc offset duty cycle as well as any modulation parameters To recall a stored state you must use the same memory location used previously to store the state From the remote interface only you can use memory location 0 to store a fourth instrument configuration you cannot store to this memory location from the front panel However keep in mind that memory location 0 is automatically overwritten when the power is turned off Any arbitrary waveforms downloaded to
261. store the state e You cannot recall the instrument state from a memory location that was not previously specified as a storage location For example an error is generated if you attempt to recall from memory location 2 but have never stored to that location From the remote interface a 810 State has not been stored error is generated if nothing is stored in the specified memory location MEMory STATe DELete 0 1 2 3 Delete a previously stored state and clear the memory location If nothing is stored in the specified memory location a 810 State has not been stored error is generated 153 In Chapter 4 Remote Interface Reference AM Modulation Commands AM Modulation Commands See also Amplitude Modulation starting on page 71 in chapter 3 AM Overview The following is an overview of the steps required to generate an AM waveform The commands used for AM are listed on the next page Set up the carrier waveform Use the APPLy command or the equivalent FUNC SHAP FREQ VOLT and VOLT OFFS commands to select the function frequency amplitude and offset of the carrier waveform You can select a sine square triangle ramp or arbitrary waveform for the carrier Select the shape of the modulating waveform You can modulate the carrier with a sine square triangle ramp noise or arbitrary waveform Use the AM INT FUNC command to select the modulating waveshape Set the modulating
262. stortion DC to 20 kHz 0 04 Spurious non harmonic Output DC to 1 MHz 65 dBc Output 1 MHz 65 dBc 6 dB octave Phase Noise 55 dBc in a 30 kHz band SIGNAL CHARACTERISTICS Square wave Rise Fall Time lt 20 ns Overshoot lt 496 Asymmetry 1 5 ns Duty Cycle 20 to 80 to 5 MHz 40 to 60 to 15 MHz Triangle Ramp Arb Rise Fall Time 40ns typical Linearity lt 0 1 of peak output Settling Time lt 250 ns to 0 5 of final value Jitter lt 25ns OUTPUT CHARACTERISTICS Amplitude into 509 2 Accuracy at 1 KHz Flatness 100 kHz 100 kHz to 1 MHz 1 MHz to 15 MHz 1 MHz to 15 MHz 50 mVpp 10 Vpp 1 of specified output sine wave relative to 1 kHz 196 0 1 dB 1 596 0 15 dB 296 0 2 dB Ampl 3Vrms 9 596 0 3 dB Ampl lt 3Vrms Offset into 500 3 Accuracy 5 Vpk ac dc 2 of setting 2 mV Output Impedance 50 ohms fixed Resolution 3 digits Amplitude and Offset Output Units Vpp Vrms dBm Isolation 42 Vpk maximum to earth Protection Short circuit protected 15 Vpk overdrive lt 1 minute 1 Add 1 10th of output amplitude and offset specification per C for operation outside of 18 C to 28 C range 1 year specification 2 100 mVpp 20 Vpp amplitude into open circuit load 3 Offset lt 2 X peak to peak amplitude 4 For square wave outputs add 2 of output amplitude additional error 298
263. sweep time specifies the number of seconds required to sweep from the start frequency to the stop frequency The number of frequency points in the sweep depends on the sweep time you select and is automatically calculated by the function generator e Sweep time 1 ms to 500 seconds The default is 1 second e The function generator computes between 2 048 and 4 096 frequency points from the start frequency to the stop frequency e Front Panel Operation 3 SWP TIME SWP MENU e Remote Interface Operation SWEep TIME seconds MINimum MAXimum Sweep Mode You can sweep with either linear or logarithmic spacing The output frequency of a linear sweep changes linearly during the duration of the sweep For logarithmic spacing the output frequency changes exponentially during the duration of the sweep e Sweep mode Linear or Logarithmic Te default is Linear e Front Panel Operation 4 SWP MODE SWP MENU e Remote Interface Operation SWEep SPACing LINear LOGarithmic 96 Chapter 3 Features and Functions Frequency Sweep Sweep Trigger Source In the triggered sweep mode the function generator outputs a single sweep each time a trigger is received After one sweep from the start frequency to the stop frequency the function generator waits for the next trigger while outputting the start frequency e Sweep trigger source Internal Single or External The default is Internal e When the in
264. sync signal is a TTL high when the output is positive relative to zero volts or the dc offset value The signal is a TTL low when the output is negative relative to zero volts or the dc offset value The sync signal is output from the front panel SYNC terminal Front Panel Operation Press the Freq key and select any valid frequency for the selected function the present amplitude and offset voltage are used Remote Interface Operation FREQuency lt frequency gt MINimum MAXimum You can also use the APPLy command to select the function frequency amplitude and offset of the carrier with a single command 86 Chapter 3 Features and Functions Burst Modulation Burst Count The burst count defines the number of cycles to be output per burst Used only in the triggered burst mode internal or external source Certain combinations of burst count and carrier frequency are not allowed If you attempt to specify a burst count that is not valid the function generator will automatically adjust the count to the maximum value allowed with the present carrier frequency Make sure you note the restrictions in Burst Carrier Frequency starting on page 85 before setting the burst count e Burst count 1to 50 000 cycles in 1 cycle increments You can also select an infinite burst count The default is 1 cycle e When the internal trigger source is selected the specified number of cycles is
265. t Output MENU 1 HPIB ADDR gt 2 INTERFACE gt 3 BAUD RATE 4 PARITY gt 5 LANGUAGE F CALibration MENU 1 SECURED or 1 UNSECURED gt 2 CALIBRATE gt 3 CAL COUNT gt 4 MESSAGE The commands enclosed in square brackets are hidden unless the function generator is UNSECURED for calibration Display Annunciators tee Agilent ute Fac Waveform Generator Num Arb pi e K MK i MK MK i K K H w I K K LLN CL EL EL ELS ELN EL PLN Z v Adrs Rm rig AM FM Ext FSK Burst Swp ERR Offset Shift amp Adrs Function generator is addressed to listen or talk over a remote interface Rmt Function generator is in remote mode remote interface Trig Function generator is waiting for a single trigger or external trigger Burst Sweep AM AM modulation is enabled FM FM modulation is enabled Ext Function generator is set for an external modulation source AM FSK Burst FSK FSK frequency shift keying modulation is enabled Burst Burst modulation is enabled Swp Sweep mode is enabled ERROR Hardware or remote interface command errors are detected Offset The waveform is being output with an offset voltage Shift Shift key has been pressed Press Shift again to turn off Num Enter Number mode is enabled Press Shift Cancel to disable Arb Arbitrary waveform function is enabled N Sine waveform function is enabled Fl Square waveform function is enabled T
266. t State e Disabled On e On Power On Reset State Internal Power On Reset State e 10 e GPIB IEEE 488 e 9600 baud e None 8 data bits Power On Reset State Secured For your convenience this table is duplicated on the rear cover of this manual and on the Quick Reference Card 123 124 Remote Interface Reference Remote Interface Reference e SCPI Command Summary starting on page 127 e Simplified Programming Overview starting on page 136 e Using the APPLy Command starting on page 138 e Output Configuration Commands starting on page 145 e AM Modulation Commands starting on page 154 e FM Modulation Commands starting on page 157 e Burst Modulation Commands starting on page 160 e Frequency Shift Keying Commands starting on page 167 e Frequency Sweep Commands starting on page 170 e Arbitrary Waveform Commands starting on page 174 e Triggering starting on page 186 e System Related Commands starting on page 188 e Calibration Commands starting on page 193 e RS 232 Interface Configuration starting on page 195 e RS 232 Interface Commands starting on page 200 e The SCPI Status Registers starting on page 201 e Status Reporting Commands starting on page 209 e An Introduction to the SCPI Language starting on page 211 e Halting an Output in Progress starting on page 216 e To set the GPIB address on page 217 e To select the remote interface on page 218 e To set the baud rat
267. ted Hardware Lines IEEE 488 2 Common Commands ATN Attention CLS IFC Interface Clear ESE lt enable value gt REN Remote Enable ESE SRQ Service Request Enable ESR IDN OPC Addressed Commands OPC PSC 0 1 DCL Device Clear PSC EOI End or Identify Terminator RST GET Group Execute Trigger SAV 0 1 2 3 GTL Go To Local RCL 0 1 2 3 LLO Local Lockout SRE enable value SDC Selected Device Clear SRE SPD Serial Poll Disable STB SPE Serial Poll Enable TRG eS Te WAI Capability Identification Codes SH1 AH1 T6 L4 SR1 RLI1 PPO DC1 DT1 CO E2 225 226 Error Messages Error Messages e Errors are retrieved in first in first out FIFO order The first error returned is the first error that was stored When you have read all errors from the queue the ERROR annunciator turns off The function generator beeps once each time an error is generated e Ifmore than 20 errors have occurred the last error stored in the queue the most recent error is replaced with 350 Too many errors No additional errors are stored until you remove errors from the queue If no errors have occurred when you read the error queue the function generator responds with 0 No error e The error queue is cleared when power has been off or after a CLS clear status command has been executed The RST reset command does not clear the error queue e Front Panel Operation 3 ERROR SYS
268. ternal trigger source is enabled default the function generator outputs a continuous sweep at a rate determined by the sweep rate specified e Pressing Single to enable the single trigger mode also enables the external trigger mode External triggering is like the front panel single trigger mode except that you apply a trigger signal to the rear panel Ext Trig terminal The function generator is triggered on the rising edge of a TTL pulse e The Trig annunciator turns on when the function generator is waiting for a single or external trigger e Front Panel Operation Pressing Single to enable the single trigger mode also enables the external trigger mode Press Shift Internal to enable the internal trigger mode e Remote Interface Operation TRIGger SOURce IMMediate EXTernal BUS See Triggering on page 98 for more information 97 Chapter 3 Features and Functions Triggering Triggering Applies only to bursts and frequency sweep You can issue triggers for bursts and sweeps using internal triggering single triggering or external triggering e Internal or automatic triggering is enabled when you turn on the function generator In this mode the function generator outputs continuously when the burst mode or sweep mode is selected e Single triggering outputs one burst or initiates one sweep each time you press Single from the front panel Continue pressing
269. the AM annunciator flashes indicating that the displayed parameter is for AM Save the change and turn off the menu The modulating waveform is now a sine waveform ENTERED Set the modulating frequency to 200 Hz Notice that the AM annunciator flashes indicating that the displayed frequency is the modulating frequency for AM Also notice that the modulating frequency is displayed with fewer digits than the carrier frequency For more information on editing numbers in the menu refer to Menu Example 3 earlier in this chapter ZTN MOD 200 0 Hz d This message appears on the display for approximately 10 seconds Repeat this step as needed Chapter 2 Front Panel Menu Operation To output a modulated waveform Shift Level 7 Set the modulation depth to 80 Notice that the AM annunciator flashes indicating that the displayed percentage is the AM depth also called percent modulation 080 DEPTH EP Nee This message appears on the display for approximately 10 seconds Repeat this step as needed At this point the function generator outputs the AM waveform with the specified modulation parameters 43 Shift FSK Shift lt Recall Menu n 2 Chapter 2 Front Panel Menu Operation To output an FSK waveform To output an FSK waveform You can configure the function generator to shift its output frequency between two preset values usin
270. the average amplitude is zero since the waveform has equal positive and negative half cycles Since the quantity of interest is the heating value of the signal the average value of a sine wave is taken to mean the average of the full wave rectified waveform The RMS value of a sine wave is equal to 1 11 times the sine wave average amplitude This relationship does not hold true for other waveshapes 285 Chapter 7 Tutorial Attributes of AC Signals dBm The decibel dB is commonly used to describe RMS voltage or power ratios between two signals By itself a decibel value has no particular meaning Decibels are a ratio or comparison unit and have no absolute meaning without knowledge of a reference or comparison unit When power comparisons are made to a 1 mW reference level the letter m is added to give dBm For power ratios such as dBm it is common to specify the resistance loading the voltage source Often the system resistance is added to the units by indicating dBm 5097 for a 509 resistance system dB 10 x log P Pref dBm 10 x logy P 0 001 where power P V R For a 500 resistance 1 mW of power corresponds to 0 224 VRMS dBm 502 Output Voltage Level 502 load 23 98 3 53 VRMS 13 01 1 00 VRMS 6 99 500 mVRMS 0 0 224 mVRMS 6 99 100 mVRMS 13 01 50 mVRMS Use the following conversions to determine dBm levels when connecting 75Q or 6000 load resistances dBm 75 Q dBm 50
271. the function generator s output frequency alternates between the carrier frequency and a second hop frequency The rate of frequency hops is controlled either by an internal source or from an external logic input FSK is essentially a special case of frequency modulation FM where the hop frequency is another way of specifying both the deviation and the modulating signal shape The modulating signal shape is always a square wave with an amplitude of zero to 41 The deviation is either positive or negative depending on whether the hop frequency is larger or smaller than the present carrier frequency as shown below The internal FSK rate generator specifies the period of the modulating square wave signal When selected the external FSK input replaces the internal FSK rate generator to directly control the frequency hop rate A TTL low input always selects the carrier frequency and a TTL high always selects the hop frequency The logic sense of the external FSK input can effectively be changed by interchanging the carrier and hop frequency values Deviation Hop Frequency Carrier Frequency See eee An FSK waveform with a 3 kHz carrier waveform and 500 Hz hop waveform the FSK rate is 100 Hz 290 Chapter 7 Tutorial Modulation Burst Modulation In burst modulation the function generator turns the carrier wave output on and off in a controlled manner The carrier output can be
272. this key to re trigger the function generator e Pressing Single to enable the single trigger mode also enables the external trigger mode External triggering is like the front panel single trigger mode except that you apply a trigger signal to the rear panel Ext Trig terminal The function generator is triggered on the rising edge of a TTL pulse e The Single key is disabled when in remote the Rmt annunciator turns on when in remote and when a function other than burst or sweep is selected 98 Chapter 3 Features and Functions Triggering Trigger Source Choices Applies only to burst and sweep You must specify the source from which the function generator will accept a trigger From the front panel the function generator will accept a single trigger a hardware trigger from the Ext Trig terminal or continuously output bursts or sweeps using the internal trigger At power on internal trigger is selected From the remote interface the function generator will accept a software bus trigger a hardware trigger from the Ext Trig terminal or an immediate internal trigger The trigger source setting is stored in volatile memory the source is set to internal trigger front panel or immediate remote interface when power has been off or after a remote interface reset To select the trigger source from the remote interface use the following command The APPLy command automatically sets the trigger sour
273. tion you should enable FSK after you have set up the other modulation parameters FSKey STATe OFF ON 90 Chapter 3 Features and Functions Frequency Shift Keying FSK Modulation FSK Carrier Frequency Carrier frequency 10 mHz to 15 MHz 100 kHz for triangle and ramp The default is 1 kHz You can use sine square ramp triangle or arbitrary waveforms for the carrier waveform For arbitrary waveforms the maximum carrier frequency depends on the number of points specified in the waveform The five built in arbitrary waveforms can be output at a maximum of 5 MHz Number of Arb Points Minimum Frequency Maximum Frequency 8 to 8 192 8k 10 mHz 5 MHz 8 193 to 12 287 12k 10 mHz 2 5 MHz 12 288 to 16 000 10 mHz 200 kHz For an externally controlled FSK waveform the carrier frequency is output when a low TTL level is applied to the FSK terminal The hop frequency is output when a high TTL level is applied For FSK the sync signal is referenced to the FSK hop signal not the carrier A momentary TTL high pulse gt 200 ns is output on the transition to the hop frequency The signal is output from the front panel SYNC terminal Front Panel Operation Press the Freq key and select any valid frequency for the selected function the present amplitude and offset voltage are used Remote Interface Operation FREQuency lt frequency gt MINimum MAXimum You can
274. to determine the number of times it has been calibrated Your function generator was calibrated before it left the factory When you receive your function generator read the count to determine its initial value Stored in non volatile memory e The calibration count increments up to a maximum of 32 767 after which it wraps around to 0 Since the value increments by one for each calibration point a complete calibration will increase the value by many counts CALibration SECure CODE new code Enter a new security code To change the security code you must first unsecure the function generator using the old security code and then enter a new code The calibration code may contain up to 12 characters Stored in non volatile memory CALibration SECure STATe OFF ON lt code gt Unsecure or secure the function generator for calibration The calibration code may contain up to 12 characters Stored in non volatile memory CALibration SECure STATe Query the secured state of the function generator Returns 0 OFF or 1 ON 193 Chapter 4 Remote Interface Reference Calibration Commands CALibration SETup 0 1 2 3 84 Configure the function generator s internal state for each of the calibration steps to be performed CALibration SETup Query the calibration setup number Returns a value between 0 and 84 CALibration STRing quoted string Record calibration information about your function generato
275. tomatically selects the appropriate filter when the output function is selected All digital to analog converters including those used in DDS generators produce spurious signals resulting from non ideal performance These spurious signals are harmonically related to the desired output signal At lower frequencies the 33120A s 12 bit waveform DAC produces spurious signals near the 74 dBc level decibels below the carrier or output signal as described by the equation on the following page The 33120A uses the complete vertical resolution N21 of the DAC for all internal waveshapes thus minimizing amplitude quantization error 276 Chapter 7 Tutorial Signal Imperfections At higher output frequencies additional DAC errors produce non harmonic spurious outputs These are signals folded back or aliased to a frequency within the signal bandwidth A perfect DAC will also produce a wideband noise floor due to amplitude quantization The noise floor for a 12 bit DAC will be near the 74 dBc level this corresponds to a noise density of 148 dBc Hz for sine wave outputs from the 33120A Amplitude Quantization lt 20 x log Nx 4096 1 8 dBc where N is the fraction of available DAC codes used to describe the signal waveshape 0 lt N lt 1 Another type of waveform error visible in the frequency domain is phase truncation error This error results from time quantization of the output waveform Whenever a wav
276. tor temporarily rescales the waveform amplitude between 1 and 1 at 1 kHz gt 11 Move across to the LINE EDIT command on this level v 12 Move down a level and set point 100 to a value of 1 Use the left right arrow keys to move between the point field left and the floating point value right The comma at the right side of the display indicates that the displayed value is the start point For this example the first 99 points in the waveform remain at 0 00100 1 0000 Enter 13 Press Enter to store the start point and move to the end point 105 Enter Shift Menu On Off Shift lt Recall Menu gt 14 15 16 17 18 Chapter 3 Features and Functions Arbitrary Waveforms Increment to point 299 and set the end point to a value of 1 Use the left right arrow keys to move between the point field left and the floating point value right As you modify the value the end point is output When you press the Enter key the line between the start point and end point is calculated output and stored If you exit without pressing the Enter key the start point and stop point are restored 00299 1 0000 Save the start and stop points and output the waveform COMPUTING Save the waveform and turn off the menu The function generator beeps and displays a message to show that the waveform is now stored in vo
277. tput amplitude is 5 Vpp Define number of cycles Define damping factor Waveform I SIN 2 PI Ncycles I 14000 2047 Waveform I Waveform I EXP Damp factor 1 14000 267 Chapter 6 Application Programs Downloading an Arbitrary Waveform over RS 232 continued 350 360 Download data points to volatile memory 370 380 DISP Downloading Arb 390 OUTPUT Fgen DATA DAC VOLATILE 532000 Output binary block header 400 WAIT Wait for interface 410 OUTPUT Bin Waveform Output binary block 420 WAIT Wait for interface 430 OUTPUT Fgen OPC Send terminator and wait for download to complete 440 ENTER Fgen Value Enter value 450 DISP Download Complete 460 470 OUTPUT Fgen DATA COPY DAMP SINE VOLATILE Copy to non volatile memory 480 OUTPUT Fgen FUNC USER DAMP SINE Select the active waveform 490 OUTPUT Fgen FUNC SHAP USER Output the selected waveform 500 END QuickBASIC RS 232 Program 5 This program shows how to download an arbitrary waveform using ASCII data over the RS 232 interface The program generates a damped sine wave using 1 000 points npnts 1000 Define number of ASCII points in waveform NCYCLES 10 Define number of cycles DAMPFACTOR 5 Define damping factor DIM waveform npnts Dimension waveform array Configure COM2 for 9600 baud even parity 7 data bits 2 stop bits sup
278. ts syntax 127 built in arb waveforms 175 bumpers removing 27 Burst annunciator 5 burst modulation burst count restrictions 85 162 burst count selection 87 162 carrier frequency range 84 162 example program 248 external gate source 83 164 front panel operation 47 gated mode 81 160 internal rate 88 164 starting phase 89 163 sync signal 86 technical description 291 trigger source 82 165 triggered mode 81 160 Burst terminal 102 bus triggering 101 186 byte order binary data 180 185 303 Index C C examples 244 cables RS 232 196 CAL COUN command 193 CAL SEC CODE command 193 CAL SEC STAT command 193 CAL SET command 194 CAL STR command 194 CAL VAL command 194 CAL command 193 calibration overview 118 122 read count 121 193 security code 118 text message 122 to secure 120 to unsecure 119 capability codes GPIB 225 cardiac waveform 175 carriage return character 214 carrier frequency AM 72 burst modulation 84 FM 77 FSK 91 carrying handle adjustment 18 changing positions 18 removing 27 catalog of arb names 182 184 chassis ground 6 colon syntax 213 COM serial ports 199 command format SCPI 212 command syntax colon vs semicolon 213 conventions 127 terminators SCPI 214 commas in display 52 113 common commands IEEE 214 225 computer connection RS 232 196 contents 9 11 crest factor arb data 181
279. tude 59 148 selecting duty cycle 66 147 selecting frequency 57 146 selecting function 55 145 selecting load 65 151 selecting offset 62 149 selecting output units 64 150 specifications 297 301 sync signal 68 weight product 300 wiring adapter RS 232 196 308 DECLARATION OF CONFORMITY According to ISO IEC Guide 22 and CEN CENELEC EN 45014 a Agilent Technologies Manufacturer s Name Agilent Technologies Incorporated Agilent Technologies Malaysia Sdn Bhd Manufacturer s Address 815 14th St SW Bayan Lepas Free Industrial Zone Loveland Colorado 80537 11900 Penang USA Malaysia Declares that the product Product Name 15 MHz Function Arbitrary Waveform Generator Model Number 33120A Product Options This declaration covers all options of the above product Conforms with the following European Directives The product herewith complies with the requirements of the Low Voltage Directive 73 23 EEC and the EMC Directive 89 336 EEC including 93 68 EEC and carries the CE Marking accordingly Conforms with the following product standards EMC Standard Limit IEC 61326 1 1997 A1 1998 EN 61326 1 1997 A1 1998 CISPR 11 1990 EN 55011 1991 Group 1 Class A IEC 61000 4 2 1995 A1 1998 EN 61000 4 2 1995 4kV CD 8kV AD IEC 61000 4 3 1995 EN 61000 4 3 1995 3 V m 80 1000 MHz IEC 61000 4 4 1995 EN 61000 4 4 1995 0 5kV signal lines 1kV power lines IEC 61000 4 5 1995 EN 61000 4 5 1995 0 5 kV line
280. ue gt DATA DAC VOLATILE binary block gt lt value gt lt value gt DATA ATTRibute AVERage lt arb name gt DATA ATTRibute CFACtor lt arb name gt DATA ATTRibute POINts lt arb name gt DATA ATTRibute PTPeak lt arb name gt DATA CATalog DATA COPY destination arb name gt VOLATILE Xj DATA DELete arb name DATA DELete ALL DATA NVOLatile CATalog DATA NVOLatile FREE FORMa FORMa BORDer NORMa1 SWAPped Specify Byte Order BORDer GG Default parameters are shown in bold 131 Chapter 4 Remote Interface Reference SCPI Command Summary Triggering Commands see page 186 for more information TRIGger SOURce IMMediate EXTernal BUS TRIGger SOURce TRIGger SLOPe POSitive NEGative TRIGger SLOPe TRG System Related Commands see page 188 for more information DISPlay OFF ON DISPlay DISPlay TEXT lt quoted string gt DISPlay TEXT DISPlay TEXT CLEar SYSTem BEEPer SYSTem ERRor SYSTem VERSion IDN RST TST SAV 0 1 2 3 State 0 is the instrument state at power down RCL 0 1 2 3 States 1 2 and 3 are user defined instrument states MEMory STATe DELete 0 1 2 3 Default parameters are shown in bold 132 Chapter 4 Remote Interface Reference SCPI Command Summary Calibration Commands see page
281. unction frequency amplitude and offset voltage are returned as shown in the sample string below the quotation marks are returned as part of the string SIN 5 000000000000E 03 3 000000E 00 2 500000E 00 144 Chapter 4 Remote Interface Reference Output Configuration Commands Output Configuration Commands See also Output Configuration starting on page 55 in chapter 3 This section describes the low level commands used to program the function generator Although the APPLy command provides the most straightforward method to program the function generator the low level commands give you more flexibility to change individual parameters FUNCtion SHAPe SINusoid SQUare TRIangle RAMP NOTSe DC USER Select the output function The selected waveform is output using the previously selected frequency amplitude and dc offset settings If you select USER the function generator outputs the arbitrary waveform currently selected by the FUNC USER command The default is SIN Stored in volatile memory e The following matrix shows which output functions are allowed with each modulation mode Each X indicates a valid combination If you change to a function that is not allowed with the selected modulation the modulation mode is turned off Sine Square Triangle Ramp Noise Arb AM Carrier X X X X X AM Modulating Wave X X X X X X FM Carrier X X X X X FM Modulating Wave X X X X X X FSK Modulati
282. urst mode only Select from 360 degrees to 360 degrees in 0 001 degree increments The default is 0 degrees MIN 360 degrees MAX 360 degrees Stored in volatile memory e For sine square triangle and ramp waveforms 0 degrees is the point at which the waveform crosses zero volts or the dc offset value in a positive going direction For arbitrary waveforms 0 degrees is the first point downloaded to memory BM PHASe MINimum MAXimum Query the starting phase Returns a value in degrees 163 Chapter 4 Remote Interface Reference Burst Modulation Commands BM INTernal RATE frequency MINimum MAXimum Set the burst rate for internally triggered bursts The burst rate frequency defines the interval between bursts Select from 10 mHz to 50 kHz The default is 100 Hz MIN 10 mHz MAX 50 kHz Stored in volatile memory e The burst rate setting is used only when internal triggering is enabled triggered mode The burst rate is ignored when single triggering or external triggering is enabled e It is possible to specify a burst rate which is too fast for the function generator to output with the specified carrier frequency and burst count If the burst rate is too high the function generator will internally adjust it as needed to continuously re trigger the burst The adjustment is handled internally by the function generator the burst rate displayed or queried will be the same as specified BM INT
283. use all available data 16 000 points long and the full range from 0 to 4 095 DAC codes For the 33120A you do not have to change the length of the waveform to change its output frequency All you have to do is create a waveform of any length and then adjust the function generator s output frequency Remember if you create an arbitrary waveform that includes three cycles of a waveshape for example the output frequency will be three times the value displayed on the function generator s front panel When creating arbitrary waveforms you have control of both the amplitude quantization and phase truncation errors For example phase truncation harmonics will be generated when a waveform is created using the full amplitude range of the DAC 12 bits but is created using only 1 000 waveform data points In this case the amplitude quantization errors will be near the noise floor while the time quantization error will produce harmonics near the 60 dBc level Similarly amplitude quantization harmonics will be generated when you create a waveform using less than the full amplitude resolution of the function generator For example if you use only one fifth of the available amplitude resolution amplitude quantization will produce harmonics below the 60 dBc level When importing data from instruments such as oscilloscopes the data will generally range between 1 024 and 4 096 time points and between 64 and 256 amplitude points When cr
284. ust be less than or equal to the maximum frequency for the selected function plus 100 kHz 15 1 MHz for sine and square 200 kHz for triangle and ramp and 5 1 MHz for arbitrary waveforms If you attempt to set the carrier frequency to a value that is not valid the function generator will automatically adjust the carrier frequency to equal the present deviation From the front panel MAX VALUE is displayed and the deviation is adjusted From the remote interface a 221 Settings conflict error is generated and the deviation is adjusted e Front Panel Operation Press the Freq key to select any valid frequency for the selected function the present amplitude and offset voltage are used e Remote Interface Operation FREQuency lt frequency gt MINimum MAXimum 78 Chapter 3 Features and Functions Frequency Modulation FM Modulating Waveform Shape The function generator will accept only an internal modulating signal e Modulating waveform shape internal source Sine Square Triangle Ramp Noise or Arbitrary waveform The default is Sine e You can use the noise function as the modulating waveform However you cannot use the noise function or dc volts as the carrier waveform e Front Panel Operation After enabling FM press Recall Menu to go directly to the FM SHAPE command in the menu 3 FM SHAPE MOD MENU e Remote Interface Operation FM INTernal FUNCtion SINusoid SQUare TRIangle R
285. utput is an arbitrary waveform The waveform is output using the present settings for frequency amplitude and offset unless you change them The selected waveform is now assigned to the Arb key Whenever you press this key the selected arbitrary waveform is output You can also use the knob to scroll left or right through the choices in the list See Front Panel Number Entry on page 3 for more information 23 Enter Number 1 5 5 Shift v kHz m Vrms m 2 HG Chapter 1 Quick Start To output a dc voltage To output a dc voltage In addition to generating waveforms you can also output a dc voltage in the range 5 Vdc into a 50Q termination The following steps show you how to output 155 mVdc Press the Offset key and hold it down for more than 2 seconds To enter the dc voltage mode press the Offset key or any key in the top row of function keys and hold it down for more than 2 seconds The displayed voltage is either the power on value or the previous offset voltage selected DCV 0 000 VDC Enter the magnitude of the desired voltage Q1 Notice that the Num annunciator turns on and ENTER NUM flashes on the display indicating that the number mode is enabled 155 To cancel the number mode press Shift Cancel Set the units to the desired value At this point the function generator outputs the displayed dc volta
286. view 136 selecting 115 218 triggering 101 186 reserved names arb waveforms 182 reset operation 190 reset state 123 revision number firmware 113 190 RMS value 285 Rmt annunciator 5 RS 232 arb download example 267 baud rate 116 219 cables and adapters 196 configuration 195 connection to computer 196 data frame format 196 download speeds for arbs 299 handshake 198 parity and data bits 116 220 selecting interface 115 218 start bits 195 stop bits 195 troubleshooting 199 rubber bumpers removing 27 rules arb waveform names 176 182 S safety information inside front cover SCPI language command format 212 command summary 127 135 conformance information 221 introduction 211 215 language query 117 190 long form syntax 212 parameter types 215 programming overview 136 short form syntax 212 status registers 201 208 syntax conventions 127 terminators 214 version query 117 190 security code calibration factory setting 118 to change 121 self test complete 111 190 power on 111 semicolon syntax 213 serial COM ports 199 serial poll 204 service request SRQ 204 Shift annunciator 5 Shift key 14 shipping inventory 15 short form SCPI commands 212 sinc waveform 175 single triggering 100 sliding rack kit 28 software IntuiLink 1 software triggering 101 186 spacing linear sweep 96 172 logarithmic sweep 96 172 specifications 297 30
287. wn in bold 128 Chapter 4 Remote Interface Reference SCPI Command Summary Modulation Commands see page 154 for more information SOURce AM DEPTh lt depth in percent gt MINimum MAXimum AM DEPTh MINimum MAXimum AM INTernal FUNCtion SINusoid SQUare TRIangle RAMP NOISe USER AM INTernal FUNCtion AM INTernal FREQuency lt frequency gt MINimum MAXimum AM INTernal FREQuency MINimum MAXimum AM SOURce BOTH EXTernal AM SOURCe AM STATe OFF ON AM STATe Rce DEViation peak deviation in Hz MINimum MAXimum DEViation MINimum MAXimum INTernal FUNCtion SINusoid SQUare TRIangle RAMP NOISe USER INTernal FUNCtion INTernal FREQuency lt frequency gt MINimum MAXimum INTernal FREQuency MINimum MAXimum STATe OFF ON STATe C SO 2 n hj 2 22 2 2 Hj Hj Hj j Hj 2 mu S o C Rce NCYCles d cycles INFinity MINimum MAXimum NCYCles MINimum MAXimum PHASe lt degrees gt MINimum MAXimum PHASe MINimum MAXimum INTernal RATE lt frequency gt MINimum MAXimum INTernal RATE MINimum MAXimum SOURce INTernal EXTernal Gated Burst Mode SOURCe STATe OFF ON STATe z z z z z By Es ai 2 2 2 2 UU tU UJ tJ tU tU tU tU tU UJ z TRIGger SOURce IMMediate EXTernal BUS Triggered Burst Mode TRIGger SOURce Default parameters are
288. y data over the RS 232 interface you must select 8 data bits with no parity See RS 232 Interface Configuration on page 195 for more information e The following statement shows how to use the DATA DAC VOLATILE command to download eight integer points using the binary block format see also Using the IEEE 488 2 Binary Block Format below DATA DAC VOLATILE 216 Binary Data E e The following statement shows how to use the DATA DAC VOLATILE command to download eight integer points DATA DAC VOLATILE 2047 1536 1024 512 0 512 1536 2047 Using the IEEE 488 2 Binary Block Format In the binary block format a block header precedes the waveform data The block header has the following format 5 32000 Startof Jj Even Number of Bytes to Follow Data Block 32 000 bytes 16 000 points Number of Digits to Follow The function generator represents binary data as 12 bit integers which is sent as two bytes Therefore the total number of bytes is always twice the number of data points in the waveform and must always be an even number For example 32 000 bytes are required to download a waveform with 16 000 points Use the FORM BORD command to select the byte order for binary transfers in block mode If you specify FORM BORD NORM default the most significant byte MSB of each data point is sent first If you specify FORM BORD SWAP the least significant byte
289. ycle to 70 and then change the frequency to 8 MHz the function generator will automatically adjust the duty cycle to 60 the upper limit for this frequency From the remote interface a 221 Settings conflict error is generated and the duty cycle is adjusted PULSe DCYCle MINimum MAXimum Query the duty cycle setting Returns a value in percent 147 Chapter 4 Remote Interface Reference Output Configuration Commands VOLTage amplitude MINimum MAXimum Set the output amplitude for the currently active function MIN selects the smallest amplitude allowed for the selected function 50 mVpp into 50 ohms MAX selects the largest amplitude allowed 10 Vpp into 50 ohms The default amplitude is 100 mVpp into 50 ohms Stored in volatile memory Output Minimum Maximum Function Termination Amplitude Amplitude Sine 500 50 mVpp 10 Vpp Square 500 50 mVpp 10 Vpp Triangle 500 50 mVpp 10 Vpp Ramp 500 50 mVpp 10 Vpp Noise 500 50 mVpp 10 Vpp Built In Arbs 1 500 50 mVpp 10 Vpp Sine Open Circuit 100 mVpp 20 Vpp Square Open Circuit 100 mVpp 20 Vpp Triangle Open Circuit 100 mVpp 20 Vpp Ramp Open Circuit 100 mVpp 20 Vpp Noise Open Circuit 100 mVpp 20 Vpp Built In Arbs 1 Open Circuit 100 mVpp 20 Vpp 1 There are five built in arbitrary waveforms stored in non volatile memory sinc negative ramp exponential rise exponential fall and cardiac e For arbitrary waveforms the maximum amplitude will be
290. ynchronous with the carrier waveform This internal modulation signal is used to halt waveform memory addressing when the last data point is reached This modulation signal effectively gates the output on and off for the specified number of carrier wave cycles The modulation signal is then triggered by another internal burst rate signal generator which controls how often the specified carrier burst is output In external triggered burst operation the modulation signal trigger source is set to the function generator s rear panel Ext Trig terminal This source replaces the internal burst rate signal generator for pacing triggered bursts Changes to the burst count burst rate burst phase or carrier frequency will cause the function generator to automatically compute a new modulation signal and download it into modulation RAM It is not possible for the function generator to burst single cycles for all carrier frequencies because the internal modulation signal generator is not as capable as the main carrier signal generator The table below shows the function generator s carrier frequency and burst count limitations Carrier Minimum Frequency Burst Count 10 mHz to 1 MHz gt 1 MHz to 2 MHz gt 2 MHz to 3 MHz gt 3 MHz to 4 MHz gt 4 MHz to 5 MHz For sine square and arbitrary waveforms only akhwWNnN 292 Chapter 7 Tutorial Modulation Internal Modulation Source Internally the function ge
291. z SWEep SPACing LINear LOGarithmic Select linear or logarithmic spacing for the sweep The default is Linear Stored in volatile memory SWEep SPACing Query the sweep mode Returns LIN or LOG SWEep TIME seconds MINimum MAXimum Set the number of seconds required to sweep from the start frequency to the stop frequency Select from 1 ms to 500 seconds The default is 1 second MIN 1 ms MAX 500 seconds Stored in volatile memory The number of frequency points in the sweep depends on the sweep time you select and is automatically calculated by the function generator 171 Chapter 4 Remote Interface Reference Frequency Sweep Commands SWEep TIME MINimum MAXimum Query the sweep time Returns a value in seconds SWEep STATe OFF ON Disable or enable the sweep mode To ensure proper operation you should enable the sweep mode after you have set up the other sweep parameters Only one modulation mode can be enabled at a time When you enable the sweep mode the previous modulation mode is turned off SWEep STATe Query the state of the sweep mode Returns 0 OFF or 1 ON TRIGger SOURce IMMediate EXTernal BUS Select the trigger source In the triggered sweep mode the function generator outputs a single sweep each time a trigger is received After one sweep from the start frequency to the stop frequency the function generators waits for the next trigger while outputting the
292. zero for lt 100 modulation as this equation shows D is the modulation depth 0 x D x 1 2 Am is the modulating signal with peak amplitude x 1 Fc is the carrier frequency 1 Dx Am t x sin 2x x Fcx t 2 An AM waveform with 80 modulation depth The carrier waveform is a 5 kHz sine wave and the modulating waveform is a 200 Hz sine wave 287 Chapter 7 Tutorial Modulation In amplitude modulation the amplitude of the carrier varies between zero and twice its normal value for 100 modulation The percent modulation depth is the ratio of the peak information signal amplitude to the constant When amplitude modulation is selected the 33120A automatically reduces its peak to peak amplitude by one half so that a 100 modulation depth signal can be output Amplitude settings are defined to set the 100 peak to peak amplitude independent of the modulation depth setting Vrms and dBm amplitude settings are not accurate in AM since signals are very complex Frequency Modulation FM Frequency Modulation is a process of producing a wave whose frequency varies as a function of the instantaneous amplitude of the modulating information signal The extent of carrier frequency change is called deviation The frequency deviations are caused by the amplitude changes of the modulating information signal You can set the amount of the peak frequency in FM with the deviation parameter In frequency mo

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