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Model 994 Dual Counter/Timer Operating and Service Manual

1. w 144 INPUT B POLARITY Fig 1 Selecting Counter Source W3 and W4 and Setting Input Polarity W5 and W6 WA is associated with Counter B and like W3 the two positions are labeled Time and Counts In the Time position Counter B accepts signals from Input B unless the External time base is selected In the External position Counter B counts the time base pulses to give the elapsed time for the counting interval In the Counts position Counter B always accepts the signals from Input B The 994 is shipped from the factory with W3 set to the Time position and W4 set to the Counts position 3 3 GENERAL The Model 994 Dual Counter and Timer operates on power furnished from a NIM standard bin and power supply such as the ORTEC 4001 4002D Series If the bin and power supply does not contain a 6 V power supply an optional internal 6 V supply is available for the 994 that derives its power from the 117 Vac supply in the bin 3 4 CONNECTION TO POWER Always turn off the bin power supply before inserting or removing any modules The power supply voltages should be checked after all modules have been inserted The 4001 4002D series has test points on the power supply control panel to permit monitoring of the dc voltages When power is applied to the 994 an automatic reset function clears the counters to zero and provides a standard set of start up conditions 1 display select set to Counter A 2 p
2. rc cc p pnm ette a tada 4 DD INTEREAGES 555585 EEIS SPRSASEPRSSIRCPSPIROREPISORESOTORUACER 5 2 7 ELECTRICAL AND MECHANICAL 5 2 8 ORDERING INFORMATION 4 6 S ANSEALEATION wi 6 3 1 INPUT POLARITY 6 3 2 COUNTER INPUT SELECT JUMPERS 6 35 GENERAL SS estu nasa i tM tee ete fa dec E ace ee E AMAN dee sect dete MADE gate 7 3 4 CONNECTION POWER 7 35 SIGNAL CONNECTIONS 7 3 6 OUTPUT CONNECTIONS 8 3 7 PRESET TIME OPERATION 8 3 8 PRESET COUNT OPERATION 9 3 9 LIVE TIME 6 9 4 OPERATING INSTRUCTIONS 10 4 1 RS 232 C INTERFACE MODEL 99 1 10 4 1 1 20 mA CURRENT LOOP OUTPUT 11 4 1 2 USING THE 99X 1 WITH 11 4 1 8 INSTAL
3. 25 30 30 30 30 30 30 30 36 39 OA 200000000 6 9 DEVA The next command will load a preset value to the 994 This is an example of a command that must include parameters DEV4 ibwrt set count preset 25 6 n 100 CMPL COUNT 22 DEV4 ibrd 12 2100 END CMPL COUNT 11 25 30 30 30 30 30 30 30 20000000 36 39 0A 69 DEVA The above command should have loaded a preset value of 25 X 10 Press the Display Select push button until Preset is selected for display The display should show 256 The next command should reset the preset value to zero DEV4 ibwrt clear_count_preset n 100 CMPL COUNT 19 DEVA The display should now read 000 Press the Display Select until Counter A is selected for display The display should read O DEV4 ibwrt start n 100 CMPL COUNT 6 DEV4 ibrd 12 2100 END CMPL COUNT 11 DEV4 The Gate light should be On and the counter display should be advancing DEV4 ibwrt stop n 100 CMPL COUNT 5 DEV4 ibrd 12 2100 END CMPL COUNT 11 25 30 30 30 30 30 30 30 0000000 36 39 0A 69 26 DEV4 The counting should be stopped and the Gate light should be Off The next command asks for the counter contents with the SHOW COUNTS command DEV4 ibwrt show countsin 100 CMPL COUNT 12 DEV4 ibrd 20 2100 END CMPL COUNT 19 30 30 30 3X 3X 3X 3X 3X 000XXXXX 3B 30 30 30 30 30 30 30 0000000 30 3B 0 0 DEV4 ibrd 12 210
4. DISPLAY Push button selects the contents of Counter A or B or the PRESET value for presentation in the 8 decade display Repeatedly pushing the button cycles the selection through the three choices as indicated by the A Preset and B LEDs SELECT Push button chooses the M N or P digit in the display of the preset value Pushing the button advances the selection through the three choices as indicated by the illuminated LED The Select push button operates only if the Preset mode has been selected by the Display push button Advance Push button increments the preset digit selected by the Select push button once each time the Advance button is depressed The M and N digit ranges are both 0 to 9 The P digit range is from O to 6 The Advance push button operates only if the Preset mode has been selected by the DISPLAY push button TIME BASE Each push on this button advances the selection one step through the three time base choices of 0 01 Sec 0 01 Min and Extto determine the time base source for the preset register STOP This push button stops all sections of the instrument from counting RESET Depressing this button resets the counter to zero counts and turns off the overflow indicator It also clears any counts accumulated in the blind preset register but does not change the selected preset value When power to the module is turned on a RESET is automatically generated COUNT Pushing this button enables the counting condi
5. The basic Model 994 includes an 8 decade LED display which offers instantaneous visual readout of the full contents of Counter A or B even in a dimly lighted room By adding field installable options considerably enhanced readout control capabilities can be incorporated The full power of CCNIM Computer Controlled NIM can be obtained by adding the IEEE 488 option or the RS 232 C option These plug in boards yield computer control of all functions normally selectable from the front panel including start and stop count readout reset setting the preset value selecting the displayed counter and selecting the desired time base To eliminate accidental operator interference the computer can disable all front panel controls in the Remote mode Computer readout with either of the two CCNIM options includes A and B counts the preset value and which counter is being displayed IEEE 488 option also reads the overflow status for both counters Implementation of the IEEE 488 interface in the Model 994 is compatible with the NIM GPIB standard The CCNIM options can directly drive printers having RS 232 C or IEEE 488 ports For automated counting applications not requiring computer interfacing the standard ORTEC print loop function is available as a field installable plug in board In conjunction with an ORTEC Model 7 7A Printer this option offers automatic recycling of the counting and printing of all eight digits o
6. 140 MSG SET COUNT PRESET STR MN 40 150 PRINT 1 MSG 160 REM READ RESPONSE RECORD FROM 994 170 INPUT 1 RESP 180 REM CHECK FOR CORRECT EXECUTION OF COMMAND 190 IF RESP lt gt OK THEN PRINT RESP STOP 200 REM READ VALUE BACK AND CHECK IT 210 PRINT iH SHOW COUNT PRESET 220 INPUT 1 ANSS 230 INPUT 1 RESP REM TWO RESPONSE RECORDS FOR A SHOW COMMAND 240 A MIDS ANS 3 3 250 A VAL AS IF A lt gt MN THEN PRINT STOP 260 NEXT MN REM LOOP UNTIL ALL VALUES HAVE BEEN TESTED 270 REM CHECK FOR CORRECT LOADING OF P VALUES 280 FOR P 0 6 STEP 1 290 REM LOAD P VALUES 300 PRINT 1 SET COUNT PRESET 01 P 310 REM READ RESPONSE RECORD 320 INPUT 1 5 330 REM CHECK FOR CORRECT EXECUTION 340 IF RESP lt gt OK THEN PRINT RESP STOP 350 REM READ VALUE BACK FROM 994 AND CHECK FOR PROPER LOADING 360 PRINT 1 SHOW COUNT PRESET 370 INPUT 1 ANS REM READ VALUE 380 INPUT 1 RESP AEM READ RESPONSE RECORD 390 P MID ANS 6 3 400 IF P lt gt VAL P THEN PRINT ANS STOP 410 NEXT P 420 REM EXERCISE A FEW OF THE COMMANDS 430 PRINT 1 CLEAR COUNT PRESET 440 INPUT 1 RESP 450 IF RESP lt gt OK THEN PRINT RESP STOP 460 REM READ COUNTER VALUE 470 PRINT 1 SHOW COUNTS 480 INPUT 1 CNT 490 INPUT 1 RESP 500 IF RESP lt gt OK THEN PRINT RESP STOP 510 REM LOAD DISPLAY SELECT AND READ IT BACK 520 PRINT 1 SET_DI
7. The IEEE 488 GPIB interface is a separate PWB that plugs into the module counter board and is held in place with two screws The connector containing the signals for bus communications is mounted to the board and is accessible through the rear panel of the module The placement of the connector is in accordance with the Standard NIM Digital Bus NIM GPIB with pin 1 of the connector to the top of the module When power is applied to the module a series of self test routines is executed to test certain parts of the module A response record is created to show the results of the tests This response record must be read by the bus controller before the module will accept any command A service request SRQ is issued to notify the controller that service is required before commands can be accepted Commands sent to the module must be terminated with ASCII carriage return and line feed characters For every command received by the module a response record is returned and must be accepted by the controller before another command can be issued In case of a SHOW command to the module two response records must be read by the controller All response records from the module will be terminated with a carriage return line feed sequence with the EOI line asserted along with the line feed character Table 5 shows the switch configuration for address selection of the device on the bus Fig 4 The address selected is the total of the switche
8. 994 This is done with the command ibrd xx where xx is the number of bytes to be read This number must be as large as or larger than the number of bytes expected Most response records from the 994 will be 11 bytes long including the line feed terminator One exception is the contents of the counters in the SHOW COUNTS command which is 19 bytes long Others may be shorter than the 11 bytes Appendix B 25 DEV4 ibrd 12 2100 END CMPL COUNT 11 25 30 30 31 30 30 30 30 37 30 OA DEVA 20010000 70 In the above example the second line is the status register contents the third line is the number of bytes transferred by the 994 module to the computer the fourth and fifth lines show the characters transferred with the hexadecimal value on the left and the ASCII characters on the right Now the 994 is ready to accept commands from the computer The next example sends a SHOW VERSION command to the 994 that will cause the 994 to send the version of firmware installed in the module The n characters in the command cause the computer to send a line feed new line character along with the command This must be included before the 994 will execute the command DEV4 ibwrt show version n 100 CMPL COUNT 13 DEV4 Now read the version number DEV4 ibrd 12 2100 END CMPL COUNT 11 24 46 30 39 39 36 2D 30 30 31 OA FO994 0 0 1 DEVA Now read the response record DEVA ibrd 12 2100 END CMPL
9. Remove the two screws on the top of the power supply chassis which secure it to the bracket mounted on the bottom left module bar and move the power supply chassis out of the module 5 On the interface board set the switches to the desired positions using Tables 3 and 4 to match the device to which it will be connected 6 Install the interface board into the module sliding the RS 232 C connector through the slot in the rear panel of the module first and align the 40 pin connector on the back of the board with the pins provided on the counter board Use care to ensure proper match up of connector and pins 7 Install the two mounting screws into the standoffs provided on the counter board 8 Reinstall the power supply chassis if one is present 9 Replace side panels and complete installation is 4 2 IEEE 488 GPIB INTERFACE MODEL 99X 2 The IEEE 488 1978 standard bus is a byte serial bit parallel interface system established primarily for the transfer of data and commands between the components of an instrumentation network The system is defined for no more than 15 devices interconnected by passive cabling whose total transmission length does not exceed 20 meters Data rates through any of the 16 signal lines that comprise the bus must be 1 M byte s and consist of digital data only The bus is connected in parallel to all components of the system and is designed to ensure reliable data transfer throughout the ne
10. When controlling the module from a terminal lower case letters typed at the terminal are converted to upper case by the module before echoing the characters to the terminal and evaluating the command A 1 COMMAND WORDS A command consists of words separated by under scores The first word of the command is a verb The second and third words are not always used and are called nouns and modifiers respectively The following is a typical command SHOW COUNT PRESET In the preceding command SHOW is the verb and COUNT is the noun and PRESET is the modifier Only enough letters of a word to make it unique four letters are always sufficient need be used in a command The preceding command could thus be abbreviated to SH COU PRE A 2 DATA VALUES some commands need to include data values Such values must be separated from the keywords by one or more spaces The data is also sent as ASCII characters and if more than one parameter is included in the value the parameter values must be separated by commas The following is a command with data values SET COUNT PRESET 75 3 In the preceding command the module is told to set the preset value to 75 X10 This represents a preset value of 75 000 Inthe command descriptions given in this appendix the following notation is important encloses a required value encloses an optional value A 3 CHECKSUMS A checksum may optionally be included at the end of a
11. occurred SYSTEM GATE carries a signal to all modules set for Slave operation in the system loop This signal can be used to synchronize the data collection time for all modules in the loop SYSTEM PRESET carries a signal to all modules in the system loop A preset condition stops data collection in all modules in the loop SYSTEM RESET carries a Reset signal to all modules in the loop except any that may be set for Normal This signal originates in the Master module or in the Controller module GROUND provides a common ground reference to all modules in the system loop CONTROL carries a signal to indicate when the controller is in charge of the loop This signal is used to disable the Dwell function in any module in the loop that contains this function THIS MODULE FINISHED carries a signal to the next module in the loop arrives as PREVIOUS MODULE FINISHED to indicate its turn to transfer data has occurred THIS MODULE PRINTING carries a signal to the controller to indicate to the controller that the module presently transferring data has a number other than six decades of data to transfer to the controller This line is only driven during the module s turn to transfer data 4 3 1 INSTALLATION INSTRUCTIONS To install the PRINT LOOP interface in the ORTEC Models 994 995 996 or 997 follow the steps listed below 1 Remove the left side plate from the module If the optional 6 V power supply Model 99X 4 is not
12. 704 A 73 REM COMPLETE LOOP FOR REMAINING VALUES 74 NEXT 24 75 PRINT P VALUES LOADING PROPERLY 76 REM 80REM NOW TEST START AND STOP OPERATION 81 C 96000000069 REM CORRECT RESPONSE RECORD 82 OUTPUT 704 START REM SEND START COMMAND 83 ENTER 704 A REM READ RESPONSE RECORD 85 REM DELAY LOOP TO ALLOW COUNTS TO ACCUMULATE 86 FOR 1 TO 200 NEXT 87 OUTPUT 704 STOP REM SEND STOP COMMAND 88 ENTER 704 A REM HEAD RESPONSE COMMAND 89 IF A lt gt C THEN DISP ERROR IN STOP COMMAND G STOP 90 REM NOW READ ACCUMULATED COUNTS 91 OUTPUT 704 SHOW COUNTS REM ASK FOR COUNT VALUE FROM 994 92 ENTER 704 A REM READ COUNT VALUE 93 DISP A REM VALUE PRINTED SHOULD MATCH COUNTER DISPLAY 94 READ SECOND RESPONSE RECORD FROM SHOW COMMAND 95 ENTER 704 A 96 REM END OF COMMUNICATIONS TEST 97 DISP END OF COMMUNICATIONS TEST 98 END 5 2 2 IBM PC PROGRAMMING EXAMPLES Before connecting the 994 to the IBM interface there are some important considerations regarding the setup of the software drivers which must be done before attempting to communicate with the 994 These are described in the installation and users guide which comes with the interface These include the creation or editing of a file called CONFIG SYS to let the DOS know that the interface is installed Also there are modifications which may have to be made to a file called GPIB COM This is done by running a program called IBCONF
13. In the Remote mode the computer can disable all front panel controls Computer readout includes A and B counts the preset value which counter is being displayed and the overflow status SERIAL When the RS 232 C option board is plugged in it furnishes a rear panel 25 pin male D connector containing all signals for standard RS 232 C communications It also contains connections for 20 mA current loop communications The field installable RS 232 C option provides computer control of the following functions Count Stop Reset Remote setting the preset value selecting the displayed counter and selecting the desired time base In the Remote mode the computer can disable all front panel controls Computer readout includes A and B counts the preset value and which counter is being displayed PRINT LOOP When the print loop option board is installed it furnishes a rear panel 14 pin AMP CHAMP female connector containing signals for the standard ORTEC daisy chain print loop operations This option is field installable When connected in a print loop with an ORTEC Model 7 7A Printer this option offers automatic recycling of the counting and printing of all eight digits of the A and B Counters along with any other counters in the print loop If the Model 777A is replaced with an ORTEC Model 879 Suffered Interface the print loop will have IEEE 488 and RS 232 C interface capability allowing the computer to start and stop th
14. REM TEST SERVICE REQUEST BIT 132 IF S 0 THEN GOTO 140 ELSE PRINT STARTING FROM POWER UP 133 CALL IBRD COUNTER RD REM READ POWER UP RESPONSE 134 REM 135 REM SKIP INIT COMMAND IF STARTING FROM POWER UP 136 GOTO 150 137 REM 140 REM SEND INIT COMMAND TO 994 141 WRT INIT LF REM ALL COMMANDS MUST TERMINATE WITH LF 142 CALL IBWRT COUNTER WRT REM SEND COMMAND 143 REM WAIT FOR COMMAND TO BE EXECUTED 144 FOR 1 TO 100 NEXT 145 REM READ RESPONSE RECORD FROM INIT COMMAND 146 CALL IBRD COUNTER RD 147 REM 150 REM TEST MN REGISTERS FOR LOADING AND READING 152 FOR 1 11 to 99 STEP 11 153 WRT SET COUNT PRESET STR S I 1 LFS 154 CALL IBWRT COUNTER WRT REM SEND COMMAND 155 CALL IBRD COUNTER RD REM READ RESPONSE RECORD 156 REM 157 REM READ BACK VALUES LOADED AND CHECK FOR CORRECT VALUE 158 WRT SHOW COUNT PRESET LF 159 CALL IBWRT COUNTER WRT 160 CALL IBRD COUNTER RD REM READ VALUE 161 MN MID RD 3 3 REM EXTRACT THE MN VALUE FROM RESPONSE 162 IF VAL MN lt gt THEN PRINT ERROR LOADING MN STOP 163 REM READ SECOND RESPONSE RECORD FROM SHOW COMMAND 164 CALL IBRD COUNTER RD 165 NEXT k REM COMPLETE LOOP 170 REM TEST P REGISTER FOR LOADING AND READING 172 FOR 1 TO 6 STEP 1 173 WRT SET COUNT PRESET 1 STR I LF 174 CALL IBWRT COUNTER WRT REM SEND COMMAND 175 CALL IBRD COUNTER amp RD REM READ RESPONSE RECORD
15. accomplished with the Preset Advance push button The display contains LED flags to indicate whether M N or P has been selected to warn when overflows have occurred in Counter A or Counter B and to advise when the front panel controls are disabled by the computer in the Remote mode When the Model 994 is used in the automatic recycle mode the Dwell knob adjusts the dwell time of the display from 1 to 10 seconds The counting function of the entire module can be disabled by holding the Enable input below 1 5 V using an external signal source This condition also turns off the Gate LED Open circuit or gt 3 V at the Enable input allows the instrument to count if the Count mode has been activated The Interval output of another ORTEC timer can perform this function to synchronize the Model 994 counting with the other timer The Interval outputs on all ORTEC timers provide nominally 5 V when counting and 40 5 V when counting is inhibited Independent gating of the A and B Counter inputs can be achieved with the Gate A and Gate B inputs on the rear panel Interface connectors for the IEEE 488 RS 232 C and print loop options are also located on the rear panel Each counter has a rear panel output dedicated to signaling overflows Counting these overflows on another counter extends the counting capacity of the Model 994 The Model 994 derives its power from the 12 V and 6 V supplies in a standard NIM bin with power supply For
16. already installed skip to step 5 Remove the right side panel Hemove the two screws holding the optional power supply to the bottom right module bar 4 Remove the two screws on the top of the power supply chassis which secure it to the bracket mounted on the bottom left module bar and move the power supply chassis out of the module 5 On the interface board set the switch to the desired position Master Slave or Normal 6 Set both W1 and W2 jumpers for Models 994 and 995 to the DUAL position and Model 996 and 997 to the SINGLE position 7 Install the interface board into the module sliding the PRINT LOOP connector through the slot in the rear panel of the module first and align the 40 pin connector on the back of the board with the pins provided on the counter board Use care to ensure proper match up of connector and pins 8 Install the two mounting screws into the standoffs provided on the counter board 9 Reinstall the power supply chassis if one is present 10 Replace side panels and installation is complete 4 4 INTERNAL 6 V SUPPLY OPTION MODEL 99 4 This option is available for systems that do not have a bin and power supply containing a 6 V supply it contains a transformer bridge rectifier and filter capacitor and uses the 117 Vac available in the bin to generate the voltage and power needed for the logic circuitry contained in the module Although it replaces the function of the exte
17. data transfer at end of preset Set preset time for 1 second At the end of a 1 second interval and continuing at 1 second intervals the contents of the counters will be displayed on the terminal screen 000001 00 00000000 00000100 00000000 00000100 00000000 This sequence will continue until a STOP command is sent to the 994 STOP 000000069 gt Refer to Appendix A and exercise the remainder of the commands until you are familiar with the actions and responses This will prove valuable when using the commands in a computer program Remember that for every SHOW command two response commands must be read 5 1 2 BASIC PROGRAMMING Connect the 994 to the computer via the RS 232 C cable refer to Section 4 for proper cable connections The following BASIC program for the IBM PC and compatible computers shows some of the programming methods between the 994 and the computer 20 10 REM SAMPLE PROGRAM FOR THE IBM PC AND COMPATIBLES 20 REM OPEN SERIAL PORT FOR COMMUNICATIONS 30 REM SET PORT FOR 9600 BAUD NO PARITY AND 8 DATA BITS 40 OPEN COM1 9600 N 8 AS 1 50 REM DEFINE SUCCESS RESPONSE FROM THE 994 60 OKS 000000069 70 REM INITIALIZE THE 994 TO POWER UP CONDITION 80 PRINT 1 INIT 90 REM READ RESPONSE RECORD FROM THE 994 AND STOP IF NOT OK 100 INPUT 1 RESP 110 IF RESP lt gt THEN PRINT RESP STOP 120 REM TEST M AND REGISTERS FOR PROPER LOADING 130 FOR MN 1 TO 99 STEP 1
18. ee eee eee 29 AA RESPONSE FROM THE MODULE 339 nana RR ER EE ER he ha Aa Se wae ee 29 A 5 TIME UNITS USED IN COMMANDS 4 29 A 6 CATALOG OF COMMANDS FOR THE 994 29 APPENDIX B RESPONSE RECORDS FROM THE 994 MODULE 33 BL DELIMITING CHARACTERS ea qa Q 33 52 PERHGENT RESPONSE RECORDS vasen a b nd Dc d eae et 33 DOLLAR RESPONSE RECORDS 34 APPENDIX G OPTIONAL FARTSIIST usce aaa maaa anata ana na aaa TESTS 35 C ls lt GABLES AND CONNEGIORS 35 C 2 ORDERING INFORMATION SAFETY INSTRUCTIONS AND SYMBOLS This manual contains up to three levels of safety instructions that must be observed in order to avoid personal injury and or damage to equipment or other property These are DANGER Indicates a hazard that could result in death or serious bodily harm if the safety instruction is not observed WARNING Indicates a hazard that could result in bodily harm if the safety instruction is not observed CAUTION Indicates a hazard that could result in property damage if the safety instruction is not observed Please read all safety instructions carefully and make sure you understand them fully before attempting to use this product In additi
19. gt where is the ASCII percent character the next three bytes xxx are a code for the general type of error the second three bytes yyy are the specific type of error and the final three bytes ccc are the checksum bytes Appendix A lt DL gt is an appropriate delimiting character Appendix B Records beginning with 001 002 and 004 can be OR ed together to obtain composite error indications That is the indication of power up and self test results must all be considered in order to determine what actually happened in the event of an error For example see code below 005 002 could be derived by OR ing 001 with 004 power up just occurred and a self test failed with the 002 indicating that the ROM 1 test failed The following are percent code assignments response Command executed successfully 000 000 CCC Power up just occurred 9001 000 Power up self test failed 004 002 CCC ROM test failed 004 008 CCC RAM test failed Command syntax error 129 001 CCC 129 002 CCC 129 004 CCC 129 008 CCC 129 128 CCC 129 129 CCC 129 130 CCC 129 131 CCC 129 132 CCC invalid verb invalid noun invalid modifier invalid command data invalid first data value invalid second data value invalid third data value invalid fourth data value invalid command Communications error 130 001 CCC 130 002 CCC 130 004 CCC UART buffer overrun UART parity error UART framing erro
20. of the module This connector is wired as a DTE data terminal equipment device as defined in the RS 232 C standard The 20 mA current signals are also included on this connector The signal connections are shown in Table 1 The signal names in upper case are the 20 mA current connections and the RS 232 C signal names are shown in lower case When this interface is connected to another DTE device such as a computer or terminal a null modem cable must be used to match the proper signals between the two devices These cables are available at most computer equipment suppliers or directly from ORTEC See Appendix C Optional Parts List The connections of the null modem cable are given in Table 2 The serial option is a full duplex asynchronous communications interface with a selectable baud rate from 50 to 19 200 The baud rate selection is made via a 4 position DIP switch located on the PWB Fig 3 The baud rate selected must match exactly the baud rate of the device to which the module is connected The switch settings are given in Table 3 Table 1 RS 232 C Connections Signal Signal 1 protective ground 14 transmit data 15 receive data 16 2 3 4 request to send 17 POSITIVE TRANSMIT 5 Clear to send 6 data set ready 7 8 signal ground 20 data terminal ready 23 POSITIVE RECEIVE 24 NEGATIVE TRANSMIT NEGATIVE RECEIVE Table 2 Null Modem Cable Connections Pin Pin Computer No No 994 Pr
21. prevent multiple counting As a slow signal approaches the threshold a small spurious noise pulse can traverse the threshold level and return causing an extra count to be added When using the negative inputs the threshold pots should be set at 1 V This prevents any accidental triggering due to high ground currents present at counting rates of 100 MHZ 3 2 COUNTER INPUT SELECT JUMPERS Two jumpers W3 and W4 located on the Counter Board mother board allow flexibility in selecting the input to Counter A and Counter B with respect to the Time Base Selection Fig 1 W3 is associated with Counter and the two positions are labeled Time and Counts In the Time position Counter A always counts the time base signals unless the External time base is selected in which case the signals at Input A are counted With W3 in the Time position Counter A always displays the events driving the preset counter In the Counts position the signals at Input A are always counted by Counter A regardless of the time base selection The preset counter becomes a blind timer in this position unless the External time base is selected E ne MCN 741 852 741 500 7855 COUNTS TIME w4 L INPUT A POLARITY mer 22222 0222 Se MA i 049 COUNTS use 41506 T Am 7859 155 156 J4L8244 741 8245 H a SAS eG TED p Ri RAS U42 18179051
22. uses a change in current to transmit and receive data The current loop is optically coupled to the module and can be made to be either active current for the loop supplied by the module or passive current for the loop supplied by the connected device by changing a set of jumpers on the interface board Fig 3 The transmit and receive loops can be individually selected to be active or passive The module is factory set at shipment with both the transmit and receive loops set for active The transmit and receive signals are included in the RS 232 C connector A special cable is needed when using the 20 mA current loop to connect the module to a computer or terminal This cable is available from ORTEC Appendix C Optional Parts List 4 1 2 USING THE 99X 1 WITH A PRINTER By placing the PRINT ONLY NORMAL 52 8 to the PRINT ONLY position the 99X 1 Interface will drive a printer with an RS 232 C interface directly This allows the module to generate a hard copy of the data collected without the need for commands from a computer or keyboard When the interface is installed in a Counter Timer and the module is started with the Count control each time the preset value is reached the data is automatically transferred to a printer If the Recycle mode is selected S2 6 Off the Counter data is cleared and anew cycle is started immediately If the One Cycle mode is selected 52 6 On the counter will halt until a reset is generated eith
23. 0 END CMPL COUNT 11 25 30 30 30 30 30 30 30 0000000 36 39 0A 69 DEV4 The numbers represented by the Xs in the first record should match the numbers showing in the display of the 994 Remember that two response records must be read for every SHOW command Using the above examples refer to Appendix A and exercise the remaining commands to become familiar with the commands and the response records The following is a sample program written in BASIC to show how some of the commands may be used in a program The same format holds for any programming language used The following program must be preceded by steps 1 through 99 of the program DECL BAS see Installation Instructions in the IBM Interface Manual 27 100 REM THIS PROGRAM MUST APPENDED TO DECL BAS PROVIDED 101 REM BY THE INTERFACE MANUFACTURER 102 REM 103 REM MAKE SOME ASSIGNMENTS 104 LF CHR 8HOA REM LINEFEED CHARACTER 105 COUNTERS DEV4 REM REFER DEV AS COUNTER IN PROGRAM 106 GPIBO GPIBO REM GPIBO REMAINS GPIBO 107 CALL IBFIND 0 0 108 CALL IBFIND COUNTER COUNTER 109 OK 000000069 REM RESPONSE GENERATED IF EVERYTHING 110 REM THIS PROGRAM TESTS THE COMMUNICATIONS BETWEEN THE 994 111 REM AND THE COMPUTER 112 REM 120 REM FIRST TEST THE SERVICE REQUEST TO SEE IF STARTING FROM 121 REM A POWER UP 122 REM 130 CALL IBRSP COUNTER SPR REM SERIAL POLL TO 994 131 S96 SPR AND amp H40
24. 176 REM READ BACK VALUES LOADED AND CHECK FOR CORRECT VALUE 177 WRT SHOW COUNT PRESET LF 178 CALL IBWRT COUNTER WRT 179 CALL IBRD COUNTER RD REM READ VALUE 180 P MIDS RD 6 3 REM EXTRACT THE P VALUE FROM RESPONSE 28 181 IF VAL P lt gt THEN PRINT ERROR LOADING MN STOP 182 REM READ SECOND RESPONSE FROM SHOW COMMAND 183 CALL IBRD COUNTER RD 184 NEXT 1 REM COMPLETE LOOP 190 REM TEST START AND STOP COMMANDS 191 WRT START LF 192 CALL IBWRT COUNTER WRT REM SEND START COMMAND 193 CALL IBRD COUNTER RD REM READ RESPONSE RECORD 195 ALLOW TIME FOR SOME COUNTS TO ACCUMULATE 196 FOR 1 1 TO 200 NEXT 1 REM DELAY LOOP 197 REM NOW STOP COUNTER AND READ COUNTS 198 WRT STOP LF 199 CALL IBWRT COUNTER WRT REM SEND STOP COMMAND 200 REM READ RESPONSE RECORD 201 CALL IBRD COUNTER RD 203 REM 210 REM READ COUNTS FROM 994 COUNTER 2211 WRT SHOW COUNTS LF 212 CALL IBWRT COUNTER WRT REM SEND COMMAND 213 REM READ CONTENTS OF THE COUNTER AND DISPLAY THE VALUE 214 CALL IBRD COUNTER RD REM READ VALUE 215 PRINT RD REM DISPLAY VALUE 216 REM READ SECOND RESPONSE FROM SHOW COMMAND 217 CALL IBRD COUNTER ROS 218 REM 220REM THIS CONCLUDES THE COMMUNICATIONS TEST 221 PRINT COMMUNICATIONS TEST COMPLETE 222 END 29 APPENDIX A ASCII COMMANDS TO THE MODULE This appendix describes the ASCII command format used by the 994 module NOTE
25. 4 is powered up a series of self tests are performed and the results of these tests are included in the power up response record that must be read by the Bus Controller before any other commands are sent to the 994 Before attempting to connect the 994 to the computer the address switches should be checked to ensure that the proper address is selected and does not conflict with another module connected to the bus The 99X 2 option is shipped from the factory with the address switch set for 4 If more Bit 7 Bit 5 Bit4 Bit 3 Bit 2 Bit 1 Bit 0 Undefined A Ovflo B Undefined Ready Undefined Requesting Service Undefined Fig 6 Serial Poll Status Byte F than one 99X 2 is connected to the bus the addresses of all but one will have to be changed The address may be set for any number from 0 to 31 however 0 is usually used for the controller in charge and 31 is used as the untalk and unlisten commands Section 4 2 Table 5 Another important point to consider when communicating with the 994 is the fact that the 994 always asserts the Service Request SRQ signal line on the bus when information is available for transfer This will be reset by conducting a serial poll or by reading the response record from the 994 When a serial poll is conducted a serial poll status byte is transferred to the computer This byte contains information about the status of the 994 and is defined in Fig 6 The 994 will n
26. 80 Male to female RS 232 C extension cable 3 meter length C 488 1 IEEE 488 interface cable 1 meter length C 488 4 IEEE 488 Interface cable 4 meter length 772 C1 X S Print Loop Cable with double ended connector Specify the length X in feet 3 INSTALLATION Before inserting the Model 994 into the bin set the switches and jumpers for the desired operating conditions There are several jumpers inside the 994 that allow the operator to select the input polarity and how the time is displayed The left side panel must be removed to gain access to these jumpers Also if a communications interface is installed an 8 position dip switch must be set up correctly for the particular system to which it is connected 3 1 INPUT POLARITY SELECTION The 994 accepts and counts either fast negative logic pulses or slow positive logic pulses Determine the type of input pulses that will be furnished and set the internal PWB jumpers W5 and W6 to accommodate the type of pulses selected as shown in Fig 1 The 994 is shipped from the factory with the jumpers set for positive logic pulses There are two important points to consider when supplying signals to the 994 1 A single pulse must cross the threshold level only one time Signals with overshoot or ringing will be counted more than once if such anomalies cause the signals to cross the threshold level 2 Single pulses with slow rise and fall times should be as clean as possible to
27. C connector for Counter A accepts positive unipolar signals minimum width above threshold 20 ns at a 5096 duty cycle The threshold is adjustable from 100 mV to 9 5 V via a front panel 25 turn trimpot Zn 1000 to ground dc coupled Negative Input Changing the Input Polarity Jumper position on the counter board permits selection of the fast negative logic input which is designed to accept 600 to 1800 mV pulses with fixed discriminator threshold of 250 mV Zi 500 coupled Minimum pulse width above threshold is 4 ns IN B Identical to In A except that it feeds Counter B Use of this input is affected by the B Counter Timer Jumper ENABLE Front panel BNC input connector accepts NIM standard slow positive logic pulses to control the counting condition of the entire module A level of gt 3 V or open circuit allows counting provided the instrument is in the Count mode and has not reached the preset value lt 1 5 V inhibits counting The driving source must be capable of sinking 5 mA of positive current during inhibit input protected to 25 V GATE A Rear panel BNC input is identical to the Gate B input with the following exception With the Gate A jumper on the PWB set to the Normal position the Gate A input controls counting of the In A events in Counter A By moving the PWB Gate A jumper to the Live Time position the Gate A input also controls the 10 MHZ clock to form a live time clock with a 100 ns reso
28. E RECORD 26 IF A 9600100007 THEN GOTO 30 REM TEST FOR POWER UP 27 DISP STARTING FROM POWER UP 28 REM IF POWER UP THEN SKIP INIT COMMAND 29 GOTO 40 30 REM IF NOT POWER UP INITIALIZE 994 31 OUPTUT 704 INIT 32 REM WAIT FOR INIT COMMAND TO COMPLETE 33 FOR 1 TO 200 NEXT I REM WAIT LOOP 34 REM READ RESPONSE RECORD FROM 994 35 ENTER 704 A 36 REM 40REM TEST COMMUNICATIONS FOR LOAD AND READ OPERATIONS OF MN VAL 41 FORI 1 TO 99 42 A SET COUNT PRESET amp VAL I 841 43 OUTPUT 704 A 43 ENTER 704 A REM READ RESPONSE RECORD 44 REM READ VALUE BACK TO INSURE PROPER LOADING 45 OUTPUT 704 SHOW COUNT PRESET 46 ENTER 704 A REM READ VALUE RECORD 47 A VAL AS 3 5 REM EXTRACT MN VALUE FROM RECORD 48 IF A C 1 THEN DISP ERROR LOADING MN STOP 50 REM READ SECOND RESPONSE RECORD FROM SHOW COMMAND 51 ENTER 704 A 52 REM COMPLETE LOOP FOR REMAINING VALUES 53 NEXT I 54 DISP MN VALUES LOAD OK 55 REM 60 REM NOW TEST FOR PROPER LOADING OF P VALUES 61 FORI 1TO6 62 OUTPUT 704 SET COUNT PRESET 10 7 REM LOAD P VALUE 63 ENTER 704 A REM READ RESPONSE RECORD 64 REM READ P VALUE BACK AND CHECK FOR PROPER LOADING 65 OUTPUT 704 SHOW COUNT PRESET 66 ENTER 704 A REM READ VALUE FROM 994 67 REM EXTRACT P VALUE FROM RECORD AND CHECK 68 VAL AS 6 8 70 IF A lt gt THEN PRINT ERROR LOADING P VALUE STOP 71REM READ SECOND RESPONSE RECORD FROM SHOW COMMAND 72 ENTER
29. ER FF 2 HORMAL ON OH A four position DIP switch Fig 5 is located on the PWB to select one of the three operating modes Master Slave or Normal This switch determines the role of the individual modules when contained in a counting system As a Master the module drives the system gate and the system reset lines but does not respond to a system gate driven by another device As a Slave the module does not drive the system gate or the system reset signals but does respond to both In the Normal position the module does not drive or respond to the system gate or system reset signals When used with a Model 879 controller module the usual operating mode would be the Slave mode There are two 2 position jumpers W1 and W2 located on the PWB which are labeled DUAL and SINGLE These jumpers must be set to match the number of counters on the mother board into which the interface boards are connected If used with the Model 994 or 995 the jumpers must be set to the DUAL position If used with the Model 996 or 997 the jumpers must be in the SINGLE position pT T eae aes DUAL Ove SINGLE 1 Fig 5 Selecting Operating Modes on the 99X 3 Print Loop Interface Board The Print Loop Connection is made through a 14 pin connector accessible through the rear panel of the module A standard print loop cable ORTEC Model 772 C1 is used to connect the module to the other modules in the dat
30. LATION INSTRUCTIONS 12 4 2 488 GPIB INTERFACE MODEL 99 2 12 4 2 1 USING THE 99X 2 WITH 14 4 2 2 INSTALLATION INSTRUCTIONS 14 4 3 PRINT LOOP INTERFACE MODEL 99X 3 15 4 3 1 INSTALLATION INSTRUCTIONS 16 4 4 INTERNAL 6 V SUPPLY OPTION MODEL 99X 4 17 4 4 1 INSTALLATION INSTRUCTIONS 17 5 PROGRAMMING THE 994 18 5 1 RS 232 C INTERFACE 18 5 1 1 TERMINAL OPERATION 18 5 10 BASE PROCR ANMIN cats teeta atta M 19 5 2 INTERFACING TO THE IEEE 488 06 21 5 2 1 HEWLETT PACKARD COMPUTER EXAMPLES 21 5 2 2 IBM PC PROGRAMMING EXAMPLES 24 APPENDIX A ASCII COMMANDS TO THE MODULE 29 Aila CGOMMAND WORD S cd ll SUS 29 A 2 DATA VALUES 29 23 GHEGKROUNM DO 22350 GAMA AARNA eee OE eee OR eee eee
31. Model 994 Dual Counter Timer Operating and Service Manual Printed in U S A ORTEC Part No 736780 1202 Manual Revision F Advanced Measurement Technology Inc a k a ORTEC a subsidiary of AMETEK Inc WARRANTY ORTEC warrants that the items will be delivered free from defects in material or workmanship ORTEC makes no other warranties express or implied and specifically NO WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ORTEC s exclusive liability is limited to repairing or replacing at ORTEC s option items found by ORTEC to be defective in workmanship or materials within one year from the date of delivery ORTEC s liability on any claim of any kind including negligence loss or damages arising out of connected with or from the performance or breach thereof or from the manufacture sale delivery resale repair or use of any item or services covered by this agreement or purchase order shall in no case exceed the price allocable to the item or service furnished or any part thereof that gives rise to the claim In the event ORTEC fails to manufacture or deliver items called for in this agreement or purchase order ORTEC s exclusive liability and buyer s exclusive remedy shall be release of the buyer from the obligation to pay the purchase price In no event shall ORTEC be liable for special or consequential damages Quality Control Before being approved for shipment each ORTEC instrument must pass a s
32. RS 232 C Interface Board In addition to the baud rate selection the format of the data bits ASCII characters must also be set to match the device to which the 994 is connected To accomplish this an 8 position DIP switch Fig 3 is provided to allow the operator to select the number of data bits parity enable or disable odd or even parity if enabled and either one or two stop bits These must match the device to which the module is connected Table 4 defines these selections Table 4 Data Format switch Position On 1 8 Data Bits 7 Data Bits 2 Enable Parity Disable Parity 3 Even Parity Odd Parity 4 2 stop Bits 1 Stop Bit 25 i 6 Recycle Mode One Cycle Mode 7 Counter Timer Counter Only 8 Print Only Normal Mandatory settings The 99X 1 option is shipped from the factory with the following settings Character length set to 8 bits Parity check and generation disabled Parity selection set to even Stop bit selection set for 1 Baud rate set for 9600 One cycle mode selected Counter Timer selected NORMAL CONOR ON 4 1 1 20 mA CURRENT LOOP OUTPUT The 20 mA current loop operates in exactly the same way as the RS 232 C All switch selections apply equally to the 20 current loop communications The major difference in the two modes is the electrical characteristics of the signals The RS 232 C uses a change in voltage to transmit and receive data and the 20 mA current loop
33. RTEC Model 994 Dual Counter Timer incorporates two 8 decade counters and a blind preset timer Considerable functional flexibility is designed into the instrument allowing it to be configured for a variety of measurement tasks Typically it can be used as two counters recording separate events under the control of the preset blind timer When continuous readout of the time is needed Counter A can be diverted to count the time while Counter B records external events This provides the function of a counter and a displayed preset timer In some applications the time taken to count a preset number of events must be measured For this application Counter A coupled with the preset blind counter can be used as a preset counter while Counter records the time 0 01 second intervals In measurements where it is Important to correct for the dead time of the detector and its associated electronics the Gate A input can be switched to also gate the time clock On and Off with a 100 ns time resolution A positive logic signal which defines the system live time is connected to the Gate A input This configuration provides a live time clock Counter A and a counter B Excellent flexibility in setting the preset value is offered by the MN X 10 selection The and values provide two digit precision while P selects the decade Presets can be chosen in the ranges of 0 01 to 990 000 seconds 0 01 to 990 000 minutes or 1 to 99 000 000 counts
34. S INTERVAL OUTPUT Adc level which follows the condition of the counting gate is available at this front panel connector When the counting gate is enabled the dc level is nominally at 5 V When counting is inhibited by gating by having reached preset or by being stopped manually or remotely the dc level is nominally at 0 V This output be used to gate other counters OVERFLOW OUTPUTS The counter overflow output signals are available through the BNC connectors located on the rear panel slow positive logic signal nominally 5 V 20 Us appears at the connectors each time the contents of the corresponding counter change from 99 999 999 to 0 The output signal can be used as the input to another counter to increase the total counting Capacity beyond eight decades 3 PRESET TIME OPERATION The Model 994 is designed for standard operation as a counter that accumulates counts for a fixed period of time selected by the operator At the end of this time interval it will stop and hold the data until itis reset manually or it can dwell at the preset stop for an adjustable amount of time in which the data can be read It then resets automatically and repeats the timing cycle The use of the Enable and Gate inputs are optional depending on the application Determine the time interval required for the collection of counts It preset time is not desired the preset can be disabled by selecting a value of zero for M and N
35. SPLAY 1 530 INPUT 1 RESP REM READ RESPONSE RECORD 540 PRINT 1 SHOW_DISP 550 INPUT 1 ANS REM READ VALUE BACK 560 INPUT 1 RESP REM READ RESPONSE RECORD 570 D MIDS ANS 3 3 580 IF VAL D lt gt 1 THEN PRINT ANS STOP 590 END 21 5 2 INTERFACING THE IEEE 488 BUS Of the three choices of interface the IEEE 488 interface holds the greatest potential for misunderstandings This section on programming the IEEE 488 will hopefully help smooth the interfacing The two computer systems discussed in this section are the Hewlett Packard and the IBM PC compatibles For other computers there should be enough information included to allow interfacing to the Model 994 The major difference between the Hewlett Packard computers and the IBM PC compatibles is the fact that Hewlett Packard includes software drivers in the high level languages but on the IBM compatibles the interface circuitry and the software drivers to interface to the IEEE 488 bus must be installed in order to complete the working system The most important aspect of interfacing to the IEEE 488 bus is ensuring that the address switches in the 994 are set correctly and that the correct address is used when accessing the 994 in a program statement Section 4 The other important consideration is to always read the response records from a previous command before trying to send another command otherwise the 994 will not respond Also when the 99
36. This allows the selection of the device number and address of the 994 on the bus These programs are described in detail in the Users Guide When these initial setup procedures have been completed connect the 994 to the computer and apply power to the 994 As with the H P computer it is much easier to become familiar with the command format and response records by using the computer in an immediate mode To do this with the IBM a program called IBIC must be run Type IBIC to start the program and follow instructions when the logo appears The following is a step by step example of communicating with the 994 The test appearing in upper case letters is generated by the computer commands typed by the operator are in lower case letters PRESS FI FOR HELP GPISO set dev4 DEV4 Commands to the 994 are only sent when the prompt DEV4 is present Because the 994 has just been powered up a power up response record will be waiting to be read A serial poll ibrsp command should confirm that the 994 is asserting the service request SRQ line on the bus DEV4 lbrsp 100 CMPL POLL 0X40 DEV4 The second line shows the contents of the status registers In this case it shows that the command was completed by the interface adapter The results of the poll 0X40 show that the service request was being asserted by the 994 40 hex is bit 6 of the serial poll status byte set to a 1 Next read the power up response record from the
37. a acquisition system The connections in the cable are listed in Table 6 Table 6 Print Loop Signals Pin z Signal Name Data 1 Data 2 Data 4 Data 8 Print Print Advance Previous Modute Finished System Gate 9 System Preset 10 System Reset 11 Ground 12 Control 13 This Module Finished 14 This Module Printing on DO D wh The print loop signals are included in the 14 pin connector on the Print Loop Interface board and in each of the other units in the printing loop system All of the signals except one are in parallel to all units in the system The exception is Previous Module Finished as an input to the module and This Module Finished as an output to the next module This signal ripples through the printing loop to indicate to each module when its turn to transfer data has occurred The order in which modules transfer data is determined by the cables and their relative positions in the loop DATA LINES 1 2 4 8 transfer the four bits of BCD data from the assigned module to the Controller module Each module drives these lines only during its turn for printing PRINT prepares the modules in the loop for data transfer PRINT ADVANCE advances the module through its digits during data transfer It starts with the most significant digit and scans sequentially to the lowest significant digit PREVIOUS MODULE FINISHED starts the actual data transfer from an instrument when its turn has
38. ached the data is automatically transferred to a printer If the Recycle mode is selected S2 6 Off the Counter data is cleared and a new cycle is started immediately If the One Cycle mode is selected 52 6 On the counter will halt until a reset is generated either by the front panel Reset switch or by the Dwell time expiring at which time a new counting cycle will begin When the interface is installed in a Counter Only module a counting cycle is started by the front panel Count control When the counting cycle is stopped either by pressing the Stop control or by bringing the Master Enable or Gate input low the data which has accumulated in the counter will be transferred to the printer If the Recycle mode is selected the counter will be cleared and a new data collection cycle started as soon as the counter is enabled either by the Count control if the counting was terminated by the Stop switch or by the Master Enable or Gate going high if the counting was stopped by this signal If the One Cycle mode is selected the counter will continue counting from the point of interruption without being reset when reenabled to count When power is applied to the module the Model Number of the Module and the firmware version will be printed When any of the mode switches are changed the module must be powered up again before the changes are recognized 4 2 2 INSTALLATION INSTRUCTIONS To install the IEEE 488 GPIB interface foll
39. and the counting interval can be controlled using the Count and Stop push button switches on the front panel There are two internal time bases to select from 0 01 seconds and 0 01 minutes The choice is made by pressing the Time Base Select push button until the LED indicator for the desired time base is lighted To preset the time interval select Preset as the displayed value Press the Select push button until the LED indicator for the M register is lighted Next press the Advance push button until the correct value for M appears in the display Press the Select push button and repeat the above procedure for the values of N and P The selected value is in the format of MN x 10 where MN is a number from 01 to 99 and P represents the power of 10 to which MN is raised For example to select a preset time of 15 00 seconds select an M value of 1 an N value of 5 and a value of 2 for P which represents 15 x 10 ticks of the 0 01 second time base The dwell period at the end of the preset interval is controlled by the Dwell control This is a potentiometer with an Off switch at the fully counterclockwise position In the Off position the dwell control is disabled and the data collected will be displayed until a manual reset is initiated As the potentiometer is turned clockwise the dwell period is varied from 1 second to 10 seconds at the full clockwise position At the end of the selected dwell time an automatic reset is generat
40. arameter of the command MN can be any value from 01 to 99 and N can be any value from O to 6 Command SET_EVENT_PRESET VALUE SET MODE_EXTERNAL SET MODE MINUTES SET MODE SECONDS SET DISPLAY lt VALUE gt SHOW ALARM SHOW COUNTS SHOW COUNT PRESET SHOW DISPLAY SHOW EVENT SHOW EVENT PRESET SHOW MODE 31 Minimum Letters SET EV PR SET MOD EXT SET MOD MIN SET MOD SEC SET DISP SH ALA SH_COU SH_COU_PRE SH_DISP SH_EV SH_EV_PRE SH MOD CATALOG OF COMMANDS cont d Description Loads the value a number between 1 and 99 999 999 to the event preset register Counting will be stopped when the event counter reaches that value Selects the external input to the preset counter in the 994 Selects the minutes time base as the input to the preset counter Selects the seconds time base as the input to the preset counter Selects the counter whose contents will be displayed on the 994 front panel 7 segment LEDs The value will be either 0 or 1 for Counters A and B respectively Returns a l response record showing the status of the alarm The answer is in the form of a T for true and F for false Example IF Shows the contents of Counters A and B of the 994 00000000 00000000 960000000069 Causes the 994 to transmit a D response record which includes the MN and P vaiues presently selected D015004146 96000000069 Causes the 994 to s
41. bins that do not contain a 6 V supply an Internal 6 V Supply option is available This option is field installable and derives its power from the 117 V ac lines in the bin 2 SPECIFICATIONS 2 1 PERFORMANCE COUNT CAPACITY 8 decades for counts ranging from O to 99 999 999 in each of 2 counters MAXIMUM COUNTING RATE 100 MHZ for negative input 25 MHZ for positive input TIME BASE 10 MHZ clock with minimum preset or displayed intervals of 0 01 s or 0 01 minutes Synchronizing error is nominally 100 ns Also accepts an external input from the Counter A input In A when the Ext External mode is selected TIME BASE ACCURACY lt 0 0025 over the 0 50 C operating temperature range PRESET TIME COUNTS The module stops counting when the preset value MN X 10 is reached on the blind preset register M and N are digits ranging from O to 9 P is a digit ranging from 0 to 6 With the 0 01 SEC time base preset times from 0 01 to 990 000 s can be used Preset times from 0 01 to 990 000 min are available using the 0 01 MIN time base In the EXT time base mode preset counts in the range of 1 to 99 000 000 can be used POSITIVE INPUT DISCRIMINATOR Threshold variable from 100 mV to 9 5 V with 25 turn trimpot PULSE PAIR RESOLUTION lt 10 ns for negative input 40 ns for positive input 2 2 INDICATORS COUNTER DISPLAY 8 digit 7 segment LED display with leading zero suppression When displaying time two digits to t
42. command record It is used by the module upon reception of the command to verify that the record was transmitted without error The actual checksum is a byte obtained by adding all of the bytes of the record together as if they were 8 bit unsigned binary integers Unless otherwise stated the checksum is to be transmitted as three ASCII characters representing the decimal equivalent of the binary integer decimal values range from 000 to 255 for 8 bit integers rather than a single binary byte The three checksum characters if present must be the last characters of the command record before the delimiter and must be separated from any data values by a comma If a data value is optional or not used a comma must precede the checksum for clarity A 4 RESPONSE FROM THE MODULE After a command has been transmitted from the computer or terminal to the module no other command should be issued until a response record has been received from the module The response record indicates how the module responded to the previous command and that the module is ready to receive another command Appendix B explains how the computer or terminal operator should interpret the response records A 5 TIME UNITS USED IN COMMANDS Delay is the time the module will wait before processing or responding to a command from the operator or computer Delay values must be given in special time units of 0 25 ms The computer operator must remember to enter the val
43. d The display should read 256 OUTPUT 704 CLEAR COUNT PRESET ENTER 704 A DISP A 2000000069 The display should now read 000 Select the counter for display The display should now read O OUTPUT 704 START ENTER 704 A DISP A 96000000069 The Gate light should now be On and the counter display should be accumulating counts OUTPUT 704 STOP ENTER 704 A DISP A 2000000069 The Gate light should go Off and the counting should stop OUTPUT 704 SHOW COUNTS ENTER 704 A DISP A XXXXXXXX 00000000 ENTER 704 A 20000000069 The XXXXXXXX should match the value shown in the display of the 994 Remember that for every SHOW command two records must be read Using the above examples and the information in Appendix A exercise the remaining commands to become familiar with the commands and response records The following is a sample BASIC program to demonstrate the commands and responses in a program 23 10 REM EXAMPLE PROGRAM FOR COMMUNICATING WITH THE 994 FROM 11 REM HP COMPUTER 15 ASSUMED THAT AN ADDRESS OF 415 12 REM SELECTED FOR THE 994 AND 7 IS THE NUMBER OF THE GPIB 13 REM INTERFACE IN THE COMPUTER 14 CLEAR IREM CLEAR DISPLAY 15 DIM A 25 20REM USE A SERIAL POLL TO FIND OUT IF THE 994 iS STARTING FROM 21 REM A POWER UP CONDITION 22 SPOLL 704 23 REM SKIP RESPONSE RECORD IF SERVICE REQUEST BIT NOT SET 24 IF A lt 64 THEN GOTO 30 25 ENTER 704 A IREM READ POWER UP RESPONS
44. d follow the same procedure and ORTEC will provide a quotation Damage in Transit Shipments should be examined immediately upon receipt for evidence of external or concealed damage The carrier making delivery should be notified immediately of any such damage since the carrier is normally liable for damage in shipment Packing materials waybills and other such documentation should be preserved in order to establish claims After such notification to the carrier please notify ORTEC of the circumstances so that assistance can be provided in making damage claims and in providing replacement equipment if necessary Copyright 2002 Advanced Measurement Technology Inc All rights reserved ORTEC is a registered trademark of Advanced Measurement Technology Inc All other trademarks used herein are the property of their respective owners CONTENTS VARANE ses see ee ced REED tts ecu et ode i SAFETY INSTRUCTIONS AND SYMBOLS 2 2 V SAFETY WARNINGS AND CLEANING INSTRUCTIONS vi DESCRIP HON e 1 2 SPECIFICATIONS 2 2 1 PERFORMANCE 2 SS INDICATOR ELIO ano oa bo RO TC TORO jaaa aasa aasa jamas dadada 3 DO CONT AOL Sana A DE 3 DO a 4 Do
45. de panels and the installation is complete 8 A Replace front and rear screws Ref Step 2 A 5 PROGRAMMING THE 994 5 1 RS 232 C INTERFACE To become familiar with the 994 commands and response records it is suggested that a terminal be used This allows the operator to exercise the unit and view on the terminal display exactly what must be done inside a computer program to communicate with the 994 effectively A complete list of commands and responses is given in Appendix A of this manual 5 1 1 TERMINAL OPERATION The first step whether interfacing to a terminal or computer is to ensure that the proper cables are available and that the data format and baud rate switches are set correctly Tables 3 and 4 The actual settings are not as important as ensuring that the 994 and the device to which it is connected are set to exactly the same conditions These conditions include the baud rate number of data bits parity conditions and number of stop bits Also set the 994 to the Recycle mode When these conditions have been satisfied connect the terminal to the 994 and apply power to the terminal Next apply power to the 994 A response record should appear on the terminal screen showing the results of the self test at power up If all is well the response record should be 001000070 Since the 994 powers up in the Computer mode the first command to the 994 should be to change to the Terminal mode This is done by typ
46. e counting reset the module and read the contents of the A and B Counters 2 7 ELECTRICAL AND MECHANICAL DIMENSIONS NIM standard double width module 6 90 X 22 13 cm 2 70 X 8 714 front panel per DOE ER 0457T WEIGHT Net 2 4 kg 5 2 Ib Shipping 3 7 kg 8 2 Ib POWER REQUIRED The basic Model 994 derives is power from a NIM bin furnishing 12 V and 6 V For NIM bins that do not provide 6 V an optional internal 6 V Supply is available This option is field installable and draws its power from the 117V ac lines in the bin With the Internal 6V Supply installed the power requirements are shown in column four below and column three is not applicable POWER REQUIREMENTS TABLE Internal 4 12 V 12V Bin Supplied 6 V Supply 6V 117 V ac 994 plus IEEE 488 option 125 1800 145 994 plus RS 232 C option 135 1800 145 994 plus Print Loop option 120mA 1425mA 120 2 8 ORDERING INFORMATION NOTE All three interface option boards use the same position in the module Only one can be plugged in at a given time 994 Basic module without plug in options 99X 1 RS 232 C Interface option cable not included 99X 2 IEEE 488 Interface option cable not included 99X 3 Print Loop Interface option Includes a 772 C1 Print Loop Cable 61 cm long with a double ended connector 99X 4 Internal 6 V Supply option C 75 Female to female RS 232 C null modem cable 3 meter length C
47. ed and the counting cycle will be repeated To monitor the data collected during a counting cycle press the Display Select until the LED representing the desired counter is lighted To start a counting cycle press the Stop push button then press the Reset push button and then press the Count push button The counting can be halted at any time by pressing the Stop push button If desired the cycle can be resumed from the point of interruption by pressing the Count push button without pressing Reset 3 8 PRESET COUNT OPERATION select the preset count anode of operation press the time Bass Select push button until the LED representing the External mode is lighted Now the input to the preset counter is taken from the Counter A input The preset value selection is identical to the selection of the time interval except that the preset value is in units of input counts rather than units of time aa eed LIVE TIME W1 74F151 i 74 8193 74 814608 I m a 3 9 LIVE TIME MEASUREMENTS To use the Model 994 to make live time measurements a jumper Fig 2 is provided on the Counter PWB which allows the Gate A input to also gate the timer off without affecting the counts into Counter B The time resolution for this gate is 100 ns A positive logic signal which defines the system live time is connected to the Gate A input This configuration provides a live time clock Cou
48. ement 7 selects the GPIB interface in the computer and 04 is the address of the 994 on the bus This automatically conducts a serial poll of the 994 and assigns the status byte which is an 8 bit binary value to the variable A When the variable A is displayed the value 64 is printed which is the decimal value of the 8 bit binary status byte Next the power up response record must be read before any commands will be accepted by the 994 ENTER 704 A DISP A 001000070 The ENTER statement reads the response record and assigns the input characters to the string variable A and the DISP statement prints the string to the screen In the following statements a command is sent to the 994 and the resulting responses from the 994 are read OUTPUT 704 SHOW VERSION ENTER 704 A DISP A FO994 001 ENTER 704 A DISP A 20000000069 In the above commands the firmware version installed in the 994 is asked for the string is assigned to A and displayed to the screen and the response record is read which indicates that everything is O K Remember for every SHOW command two records must be read The next statement shows a command to the 994 which includes parameters along with the command 22 OUTPUT 704 SET COUNT PRESET 25 6 ENTER 704 A DISP A 2000000069 The above command should have loaded the preset count to a value of 25 X 10 Press the Display Select push button until the preset value is displaye
49. end a response record showing the number of the counter whose contents are being displayed in the digits on the front panel 0 Counter A 1 Counter B A000245 000000069 Causes the 994 to send the contents of the event counter This is an 8 digit number G00000000235 96000000069 Causes the 994 to send the contents of the event preset register This will be an 8 digit number G00000000235 95000000069 Causes the 994 to send a record showing which input is selected for the preset counter 0 seconds 1 minutes 2 external A000245 96000000069 32 CATALOG OF COMMANDS cont d Minimum Command Letters Description EN TR ETP yn S C Ah ERE Rares ee SHOW_VERSION SH_VER Causes the 994 to send a record which shows the firmware version included in the 994 F0994 001 96000000069 START STA Causes the 994 to start a counting cycle STOP STO Stops the 994 from counting TERMINAL TER Places the 994 in the terminal mode sothat every character received is echoed to and displayed on the terminal TEST lt NUMBER gt TEST Causes the 994 to perform certain self test routines Only the ROM and RAM self tests are implemented 33 APPENDIX B RESPONSE RECORDS FROM THE 994 MODULE The 994 Timer and Counter sends various types of information to the controlling terminal or computer This appendix describes the types of responses the module makes to the various command
50. er by the front panel Reset switch or by the Dwell time expiring at which time a new counting cycle will begin When the interface is installed in a Counter Only module a counting cycle is started by the front panel Count control When the counting cycle is stopped either by pressing the Stop control or by bringing the Master Enable or Gate input low the data which has accumulated in the counter will be transferred to the printer If the Recycle mode is selected the counter will be cleared and a new data collection cycle started as soon as the counter is enabled either by the Count control if the counting was terminated by the Stop switch or by the Master Enable or Gate going high if the counting was stopped by this signal If the One Cycle mode is selected the counter will continue counting from the point of interruption without being reset when reenabled to count When power is applied to the module the Model Number of the Module and the firmware version will be printed When any of the mode switches are changed the module must be powered up again before the changes are recognized 4 1 3 INSTALLATION INSTRUCTIONS To install the RS 232 C interface follow the steps listed below 1 Remove the left side plate from the module If the optional power supply is not already installed skip to step 5 2 Remove the right side panel 3 Remove the two screws holding the optional power supply to the bottom right module bar 4
51. esentative or to should only be used for data rates of 9600 baud or the following address less higher rates require shielded cables to minimize RF interference with other devices located ORTEC in the area ATTN Nuclear Electronics 801 South Illinois Avenue Oak Ridge TN 37831 0895 U S A ORTEC Part No Module Description 459 Power Supply 6V 638630 Cable Description 25 foot male female RS 232 C cable 641810 10 foot female female RS 232 C null modem cable 641830 C 75 3 meter length female female RS 232 C null modem cable 641820 Male male gender changer 641840 3 3 foot IEEE 488 cable 603620 13 2 foot IEEE 488 cable 641720 772 C1 print loop cable 462360 918 20 mA cable C19 609820 Bin Module Connector Pin Assignments For Standard Nuclear Instrument Modules per DOE ER 0457T Pin Function 1 3 V 3V Spare bus 4 Reserved bus 5 Coaxial 6 Coaxial 7 Coaxial 8 200 Vdc 9 Spare 10 6 V 41 6V 12 Reserved bus 13 Spare 14 Spare 15 Reserved 16 12V 17 12V 18 Spare bus 19 Reserved bus 20 Spare 21 Spare 22 Heserved Function Reserved Reserved Reserved Spare Spare 24 V 24V Spare bus Spare Spare 117 V ac hot Power return ground Reset Scaler Gate Reset Auxiliary Coaxial Coaxial Coaxial 117 V ac neutral High quality ground Ground guide pin Pins marked are installed and wired in ORTEC s 4001A and 4001C Modular System Bins
52. f the contents of Counters A and B along with other counters in the print loop Instead of the 777A the ORTEC Model 879 Buffered Interface can be used to provide IEEE 488 and RS 232 C interfaces for all the counters in the print loop The Model 879 has the capability through the print loop to start and stop counting reset and read the contents of Counters A and B in the Model 994 along with the other counters in the print loop The inputs to Counters A and 6 are individually selectable as either positive or negative sensing inputs by changing the Input Polarity Jumpers on the counter printed wiring board PWB The negative input mode is designed to accept standard NIM fast negative logic pulses with a fixed threshold of 250 mV on a 50 Q input impedance The negative inputs can handle counting rates up to 100 MHz The positive input mode can accept counting rates up to 25 MHz on a 1000 Q input impedance To enhance the flexibility of the positive input mode precision discriminators are included on both counters The discriminator STANDARD NIM DIGITAL BUS NIM GPIB DOE ER 0173 U S NIM committee August 1983 IEEE Standard Digital Interface for Programmable Instrumentation ANSI IEEE Std 488 1978 The Institute of Electrical and Electronics Engineers 345 East 47 Street New York NY 10017 and Codes and Format Conventions for Use with ANSI IEEE Std 488 1978 ANSI IEEE Std 728 1982 The Institute of Electrical and Electronics E
53. git decimal numbers xxx and yyy The values will fall between 0 and 255 The command that generates the B response is SHOW COUNT PRESET The final three digits CCC represent the checksum value for the record DL is the appropriate delimiting character F xx DL The F response record is used to transmit a variable length string of printable ASCII characters shown here as xx It may consist of one or more characters No checksum is used and DL is an appropriate delimiter The command generating a F record is SHOW VERSION G xxxxxxxx lt DL gt G response record is used to transmit an 8 digit decimal value represented here as The decimal value will be between 0 and 99 999 999 The checksum represented as CCC will be a 3 digit number and DL will be an appropriate delimiting character The commands generating this record are SHOW EVENT and SHOW_EVENT_ PRESET 1x DL A 1 response record is used to transmit a single character record either an ASCII T for true or an ASCII F for false represented in the example by x DL is an appropriate delimiting character The command generating this record is SHOW ALARM 35 APPENDIX C OPTIONAL PARTS LIST C 1 CABLES AND CONNECTORS C 2 ORDERING INFORMATION A maximum cable length of 50 feet should be used Information about or orders for parts should be for the RS 232 C interface The following cables submitted to an ORTEC sales repr
54. he right of a decimal point are included OVERFLOW INDICATOR An LED indicator labeled Ovfl A and Ovfl B illuminate when the corresponding A or B Counter exceeds its capacity of 8 decades The indicator remains on until a reset is generated M N AND P INDICATORS 3 LED indicators aid in the selection of the preset value When the Preset display function is activated the Select push button will select which of the 3 LEDs is illuminated When one of these LEDs is On that digit of the preset value can be incremented using the Advance push button DISPLAY Three LEDs labeled A B and PRESET indicate the information being displayed in the counter display The Counter A Counter B or the PRESET value may be displayed by repeatedly pressing the Display push button until the desired LED is illuminated TIME BASE 3 LEDs indicate the selected time base source By repeatedly pressing the Time Base push button 0 01 Sec 0 01 Min or the Ext mode can be chosen GATE A single LED indicates that the entire instrument is enabled to count For the Gate LED to be illuminated the module must be placed in the Count mode either manually or via the interface option the Enable input must be above 3 V and the preset stop condition must not have been reached REMOTE A single LED labeled Rem indicates that the 994 is under computer control and all front panel controls are disabled This mode is set by the ENABLE REMOTE command 2 3 CONTROLS
55. ing TERMINAL and a return on the keyboard These characters will not appear on the screen but the response record 000000069 and prompt gt should appear after the return Now any characters typed on the keyboard will be echoed to the terminal display Now that communication has been established try the following commands SHOW_VERSION This command shows the version of firmware installed in the 994 F0994 001 96000000069 gt SHOW_COUNTS This command shows the contents of Counters A and B separated 00000000 00000000 by semicolon 96000000068 gt SET_COUNT_PRESET 35 4 This command loads the and P registers with the data values 000000069 included The format is lt MN P gt where MN is any number from 0 to gt 99 and P is any value from 0 to 6 SHOW_COUNT_PRESET B035004CCC gt checksum SET_DISPLAY 2 000000069 gt SET DISPLAY 0 000000069 gt Set up the 994 for automatic data collection ENABLE ALARM 000000069 gt SET COUNT PRESET 10 1 96000000069 gt START Start data collection 000000069 29 In this command the B response record shows the value loaded the preset registers 035 is the MN value 004 is the P value and CCC is This command selects the preset value to be displayed The display should show 354 for M N and P respectively This command selects Counter A and the display should read 0 00 if the internal time base is selected Enable
56. lution A level gt 3 V or an open circuit allows counting of the clock A level lt 1 5 V is used to inhibit counting of the clock during dead time intervals GATE Rear panel BNC connector accepts NIM standard slow positive logic signals to control the counting in Counter B A level gt 3 V or open circuit allows counting lt 1 5 V inhibits counting input protected to 25 V The driving source must be capable of sinking 5 mA of positive current during inhibit 2 5 OUTPUTS INTERVAL Front panel output BNC connector furnishes a positive level during the counting interval The level is nominally 5 V when counting is enabled and lt 0 5 V when counting is disabled Z 30 OVFL A Rear panel output BNC connector provides a NIM standard slow positive logic signal each time Counter A overflows its 8 decade capacity The signal has a nominal amplitude of 5 V width 20 ps OVFL Rear panel output identical to Ovfl A except that it monitors overflows from Counter B 2 6 INTERFACES IEEE 488 When the IEEE 488 option board is plugged in it furnishes a rear panel standard IEEE 488 bus connector This 24 pin AMP CHAMP female connector allows the Model 994 to lie controlled from a computer via the IEEE 488 bus The field installable option provides computer control of the following functions Count Stop Reset Remote setting the preset value selecting the display mode and selecting the desired time base
57. ngineers 345 East 47 Street New York NY 10017 thresholds are variable over the range of 100 mV to 9 5 V using front panel 25 turn trimpots The thresholds can be adjusted to suit the amplitude of a specific source of logic pulses or used as precision integral discriminators on analog pulses For the latter application the TTL logic outputs of the discriminators are provided as test points on the front panel These outputs can be used to trigger an oscilloscope while viewing the analog signal at the counter input on the oscilloscope The oscilloscope trace will show the signals that are being counted by the Model 994 thus permitting a very selective adjustment of the threshold All the commonly used functions are conveniently accessible on the front panel Manual control of the Count Stop and Reset functions is via three push buttons The Gate LED is illuminated when the Model 994 is enabled to count Selection of the 0 01 second 0 01 minute or external time base is made by the Time Base push button In the external mode the preset counter counts the events at the Counter A input The Display push button switches the display to show the contents of Counter A or the preset stop value or the contents of Counter B To change the preset value the Preset mode must first be selected with the Display push button Subsequently the Preset Select push button is used to choose M N or P for adjustment Changing the value of M N or P is
58. nter A and a counter Counter B Set jumper W1 to the Live time position for live time measurements Otherwise the W1 jumper should be set to the Normal position Lene af 7 4 9245 ja NORMAL RN 74 804 741 8192 s s XS amp R Fig 2 Selecting Live Time or Normal Mode of Operation 10 4 OPERATING INSTRUCTIONS There are three interfaces available for the module to facilitate the integration into a system environment 1 the RS 232 C Serial interface which includes a 20 mA current loop circuit 2 the IEEE 488 GPIB interface 1978 standard digital interface bus and 3 the ORTEC standard print loop interface Each of these interfaces is a separate plug in card that is easily installed in the field For bin and power supplies that do not provide the 6V needed for the logic circuitry used in the 994 an internal 6V supply is available This option is field installable and delivers regulated 5V directly to the integrated circuits on the PWB 4 1 RS 232 C INTERFACE MODEL 99X 1 This Serial Communications Interface conforms to the EIA RS 232 C Standard and contains all the circuitry needed to communicate with most ASCII terminals and with most computers equipped with a Serial Communications Port The connection is made with a standard 25 pin male D connector mounted directly to the interface printed wiring board PWB The connector is accessible through a slot in the rear panel
59. on the following symbol may appear on the product ATTENTION Refer to Manual DANGER High Voltage Please read all safety instructions carefully and make sure you understand them fully before attempting to use this product Vi SAFETY WARNINGS AND CLEANING INSTRUCTIONS DANGER Opening the cover of this instrument is likely to expose dangerous voltages Disconnect the instrument from all voltage sources while it is being opened WARNING Using this instrument in a manner not specified by the manufacturer may impair the protection provided by the instrument Cleaning Instructions To clean the instrument exterior e Unplug the instrument from the ac power supply Remove loose dust on the outside of the instrument with a lint free cloth e Remove remaining dirt with a lint free cloth dampened in a general purpose detergent and water solution Do not use abrasive cleaners CAUTION To prevent moisture inside of the instrument during external cleaning use only enough liquid to dampen the cloth or applicator Allow the instrument to dry completely before reconnecting it to the power source Vii ovrt sno men CES OWELL SELECT J Ly Y PRESET TIM JASE 01 MIN E GATE STOP RE SET COUNT THRESH 1 viii ORTEC MODEL 994 DUAL TIMER AND COUNTER 1 DESCRIPTION The O
60. ot accept another command until the response record is read The ready condition will be indicated by a serial poll status byte with only bit 4 asserted Install the Model 994 in the bin and connect the IEEE 488 bus cable to the connector on the rear panel of the 994 Turn On the power to the bin The easiest way to become familiar with programming the 994 via the IEEE 488 is to use the immediate mode of communications whereas the computer can be used as a terminal to exercise the commands This method can be used to become familiar with the protocol of the GPIB and the 994 communications structure The following examples for the Hewlett Packard and the IBM PC compatibles will show the command formats and responses from the 994 5 2 1 HEWLETT PACKARD COMPUTER EXAMPLES The first computer system discussed will be the Hewlett Packard which should apply to the HP 85 family and the 9816 9826 and the 9836 computers The computer should be set to terminate each data transfer with a line feed character Refer to the operating manual for setup procedures Since the Model 994 has just been powered up there will be a response record waiting to be transferred to the computer This response record must be read before the 994 will accept commands First a serial poll will be performed to show the service request bit set With the computer operating under BASIC execute the following commands A SPOLL 704 DISP A 64 In the above stat
61. otective ground 1 lt gt 1 Protective ground Signal ground 7 lt gt 7 Signal ground Transmit data 2 lt gt 3 Receive data Receive data 3 lt gt 2 Transmit data Request to send 4 lt gt 5 Clear to send Clear to send 5 lt gt 4 Request to send Data set ready 6 lt gt 20 Data terminal ready Data terminal ready 20 lt gt 6 Data set ready 2 Table 3 Baud Rate Selection Baud Rate S4 S3 S2 1 50 On On Off On 75 On On Off Off 110 Off Off Off Off 134 5 On Off On On 150 Off Off Off On 200 On Off On Off 300 Off Off On Off 600 On Off Off On 1200 Off On Off Off 1800 Off On Off On 2400 On Off Off Off 4800 Off On On Off 9600 Off On On On 19 200 On On On On 19 200 On On On Off 20 mA CURRENT LOOP SELECTION PASSIVE ACTIVE we 8S BU w5 TRANSMIT age wa W3 gt AW wt eB 2 r P RECEIVE 1 MM r MODEL 99x P N 6985588 R5 232 C INTERFACE SCHM 726960 2 ASSY 720710 ns ons Aagagnoagunananona wt ORTEC J B n U 5 q 9 P fy AHH U U U U eae T at 3 m orr S2 ON cof FORMAT 8 DATA BITS 1 7 DATA BITS ENABLE PARITY 2 DISABLE PARITY Eris TE z et u PARITY EVEN 3 PARITY 2 STOP BITS 4 1STOP BIT N A 5 N A RECYCLE 6 ONE CYCLE COUNTER TIMER 7 COUNTER ONLY PRINT ONLY EN NORMAL Mandatory settings Fig 3 Changing Jumpers on the 99X 1
62. ow the steps listed below 1 Remove the left side plate from the module If the optional power supply is not already installed skip to step 5 2 Remove the right side panel 3 Remove the two screws holding the optional power supply to the bottom right module bar 4 Remove the two screws on the top of the power supply chassis which secure it to the bracket mounted on the bottom left module bar and move the power supply chassis out of the module 5 On the interface board set the switches to the desired positions using Table 5 Set switch 7 to match the device to Counter Timer 6 Install the interface board into the module sliding the IEEE 488 GPIB connector through the slot in the rear panel of the module first and align the 40 pin connector on the back of the board with the pins provided on the counter board Use care to ensure proper match up of connector and pins 7 Install the two mounting screws into the standoffs provided on the counter board 8 Reinstall the power supply chassis if one is present 9 Replace side panels and complete installation is 4 3 PRINT LOOP INTERFACE MODEL 99X 3 With this interface the module can be included in a print loop with the other counters and timers from ORTEC Up to 50 counters can be included in a counting system with one controller such as the Model 879 Buffered Interface providing the interface from the loop to a computer or printout device MODE 1 MAST
63. perates in the stand alone mode Disables the event counter in the 994 Disables the event preset function IEEE 488 operation only Disables the group execute trigger command from starting the counting cycle in the 994 IEEE 488 operation only Disables the group execute trigger command from stopping the counting cycle in the 994 Causes the 994 to transfer the contents of the counters to the host at the end of a preset interval without a direct command Causes the event counter to be advanced by one count each time the preset value is reached in the 994 Enables the event counter to stop after a preset number of counting cycles have occurred Places the 994 under local control i e the front panel controls The 994 will still respond to the communications interfaces and to commands from a host Places the 994 totally under the contro of a host computer All front panel controls except the display select are disabled Enables the 994 to start a counting cycle on a group execute trigger command from the IEEE 488 bus This enables a number of counters to start simultaneously from a single trigger command Enables the 994 to stop a counting cycle on receiving a group execute trigger command from the IEEE 488 bus This is the complement to the ENABLE TRIGGER_START command Causes the 994 to restart or initialize Same as a reset or power up Sets the preset value in the 994 to the value of the MN P p
64. r 34 130 008 CCC IEEE 488 communications 131 130 CCC invalid third command parameter error 131 131 CCC invalid fourth command 9o 130 128 CCC input checksum error parameter 130 129 CCC input record too long 131 132 CCC invalid number of parameters 130 130 CCC invalid input data record 131 133 CCC invalid data other than 130 133 CCC aborted due to invalid handshake command data 131 134 CCC could not load selected value Execution error 9e 131 135 CCC counters must be stopped but were not 131 128 CCC invalid first command parameter 9o 131 129 CCC invalid second command parameter B 3 DOLLAR RESPONSE RECORDS All other response records begin with the ASCII dollar sign character and another character to indicate the particular type of dollar record The following dollar response records are available A xxx CCC DL A A record is used to transmit one 8 bit unsigned binary integer The integer is transmitted as three ASCII character digits xxx which are the decimal equivalent of the binary integer The decimal value will be between 0 and 255 The final three characters CCC are three ASCII character digits representing the checksum value for the record as a three digit decimal value DL is an appropriate delimiting character See SHOW DISPLAY and SHOW MODE commands in Appendix A B xxx yyy CCC lt DL gt A B record is used to transmit two 8 bit binary integers The integers are expressed as two 3 di
65. reset values of M N and P set to zero 3 time base select set to 0 01 Sec and 4 counters in the Stop condition 3 5 SIGNAL CONNECTIONS COUNTER INPUTS The 994 accepts and counts either fast negative logic pulses or positive pulses with an amplitude from 0 1 to 10 V see Input Polarity Selection for instructions on how to select polarity The negative input threshold is fixed at 250 mV The positive input has a front panel threshold adjustment which is variable from 100 mV to 9 5 V A test point is included on the front panel to ease the adjustment process For positive logic pulses the threshold should be set well above the noise level of the input When used with a linear signal as the input the adjustment should be set just above the amplifier noise level ENABLE INPUT gate input signal or dc level can be connected to the 994 through the Enable input on the front panel With no input to this BNC or with a voltage level gt 3 V the 994 is enabled to accept counts through the inputs on the front panel To disable the counters the input at this connector must be pulled below 1 5V To do this the driving source must be capable of sinking 5 mA of current from the Enable input circuitry GATES AAND BINPUTS The individual A and B Gate inputs BNCs are located on the rear panel The input specifications are the same as for the Enable input but only affect the inputs of the respective counters 3 6 OUTPUT CONNECTION
66. rnal 6 V supply it actually feeds 5 V power directly to the logic circuits on the PWB 4 4 1 INSTALLATION INSTRUCTIONS To install the optional Internal 6 V Supply follow the steps listed below 1 Remove both side panels 2 Mount the small L shaped bracket to the left lower module bar with two flat head screws provided Use the third and fifth holes in the module bar counting from the rear of the module 2 A f the 99X 1 or 99X 2 Option is installed on the 994 module perform the following Remove the front bottom left screw next to the Enable BNC connector and remove the rear bottom right screw see pictorial page iv the module bar can be tilted out and 99X 4 option can be mounted to it 3 Unplug the connector going to the Transistor mounted on the rear panel 4 Slide the Power Supply chassis into the module and align the two holes in the top of the chassis with the two holes on the mounting bracket Insert the two round head screws provided to secure the chassis to the mounting bracket 5 Using the remaining two flathead screws secure the chassis to the right module bar through holes three and five counting from the rear 6 Connect the power supply to the module using the connector that previously went to the power transistor on the PWB side of the rear panel 7 Theconnector to the power transistor can be left disconnected or the power transistor and connector can be removed from the module 8 Replace the si
67. s The operator must be familiar with the concept of a record that is a continuous stream of characters with a special character such as the ASCII carriage return or line feed marking its end B 1 DELIMITING CHARACTERS The end of a record transmitted between two devices must be marked by a special delimiting character The record delimiter for communications with the 994 module is either a carriage return or a line feed character or both as follows INPUT from either RS 232 C or IEEE 488 Either a carriage return or a line feed character will be accepted OUTPUT to IEEE 488 A line feed character is always used OUTPUT to RS 232 C Either a carriage return or the two character combination of a carriage return and a line feed may be appended to a record transmitted over the RS 232 C interface B 2 PERCENT RESPONSE RECORDS This type of record is called a percent record because it always begins with the ASCII percent 9e character A percent record is always transmitted after the execution of a command by the module it tells whether the command execution was successful and if not what type of error may have occurred Execution of a subsequent command cannot begin until the module has transmitted the percent response record terminating the current command Percent response records are fixed in length and have the following format the spaces are for readability and are not part of the record yyy ccc lt DL
68. s set to the Off position For example to select an address of 25 switches 1 1 4 8 and 5 16 should be set to the Off position The One Cycle Recycle switch determines the action that occurs when the counters reach a preset condition In the One Cycle mode the counters will stop at preset and hold the data until reset manually or remotely In the Recycle mode the contents of the counters will be transferred to a buffer the counters will be reset and another counting interval will be started immediately 52 ADDRESS 1 1 0 ADDRESS ADDRESS 2 2 0 ADDRESS ADDRESS 4 3 0 ADDRESS ADDRESS 8 4 0 ADDRESS ADORESS 16 0 ADDRESS RECYCLE ONE CYCLE COUNTER TIMER COUNTER PRINT ONLY NORMAL Mandatory settings Fig 4 Address Selection of Dip Switch on the 99X 2 IEEE 488 Interface Board 4 2 1 USING THE 99X 2 WITH A PRINTER By placing the PRINT ONLY NORMAL 52 8 to the PRINT ONLY position the 99X 2 Interface will drive a printer with an IEEE 488 GPIB interface directly if the printer is addressable as a Listen Only device A bus controller is not needed for this operation but only one Counting module can be connected to the printer This will allow the module to generate a hard copy of the data collected by controlling the module with the front panel controls When the inter face is installed in a Counter Timer and started by the Count control each time the preset value is re
69. t and display the events from In A B COUNTER TIMER JUMPER Two position jumper located on the PWB In the Counter position Counter B always counts and displays the events from In In the Timer position with the Ext time base selected Counter B counts and displays the time in 0 01 second intervals With either a 0 01 second or 0 01 minute time base selected Counter B counts and displays the events from In B GATE A LIVE TIME NORMAL JUMPER Two position jumper mounted on the PWB In the Normal position the signals from the rear panel Gate A connector gate the events from the In A connector In the Live Time position the signals from the Gate A connector gate the 10 MHZ clock to form a live time clock 1 CYCLE RECYCLE Selection of either the 1 Cycle or the Recycle mode can be made via an 8 pin dip switch on the IEEE 488 and the RS 232 C interface boards The Recycle mode can be used when the computer is able to respond with a data transfer when the 994 reaches the preset value Upon reaching preset the 994 latches its data into a buffer resets the counters and starts the next counting interval This process takes 50 Us The computer reads the data in the buffer before the next counting interval ends In the 1 Cycle mode the 994 simply stops counting and waits for further commands when the preset value is reached 2 4 INPUTS IN A Use of this input is affected by the A Counter Timer Jumper Positive input Front panel BN
70. ter Only 8 Print Only Normal Mandatory settings The following are descriptions for the 16 bus lines defined in the IEEE 488 bus DIO 1 THROUGH DIO 8 DATA INPUT OUTPUT These bidirectional lines are used to transfer data between devices Data is asynchronous and generally bidirectional The lines carry either data or address information depending on the state of the ATN line DAV Data Valid One of the three transfer control lines used to indicate that data is available on the DIO lines NRFD Not Read For Data Another transfer control line used to indicate that all devices are ready to accept data NDAC Not Data Accepted The third transfer control line that indicates the acceptance of data by all devices ATN Attention A bus management line used to indicate the type of data on the data lines When the ATN line is asserted DIO 1 8 carry address or commands When ATN isfalse the data lines carry only data IFC Interface Clear A bus management line which is used to place the system in a known state for system initialization SRQ Service Request A bus management line used to indicate a need for service by a device in the system REN Remote Enable A bus management line used to select either local or remote control of each device EOI End Or Identify The fifth bus management line used to indicate the end of a multiple byte transfer sequence This line is asserted with the last byte of a data record
71. tion for the entire instrument providing the Enable input is not held below 1 5 V and the preset value has not been reached THRESH ADJUST A and B Front panel mounted 25 turn trimpots to adjust the positive input threshold for the Counters A and B The range is from 100 mV to 49 5 V Adjacent test point provides the TTL logic signal output from the discriminator to facilitate adjustment using an oscilloscope DWELL A one turn potentiometer on the front panel with an On Off switch at the fully counterclockwise position adjusts the display dwell time over the nominal range of 1 to 10 seconds When the instrument is in the Recycle mode dwell time occurs after the preset value has been reached Turning the switch Off at the fully counterclockwise position selects the Single Cycle mode If the print loop option is used the Dwell control is disabled when the print loop controller is active and controlling the dwell time INPUT POLARITY JUMPERS Two jumpers located on the printed wiring board PWB separately select the desired input polarities for inputs In A and In B P positive N negative A COUNTER TIMER JUMPER Two position jumper located on the PWB In the Counter position Counter A always counts and displays the events connected to In A When set to the Timer position Counter A counts and displays the time if either the 0 01 Sec or the 0 01 Min time base is selected If the Ext time base is selected Counter A will coun
72. tringent set of quality control tests designed to expose any flaws in materials or workmanship Permanent records of these tests are maintained for use in warranty repair and as a source of statistical information for design improvements Repair Service If it becomes necessary to return this instrument for repair it is essential that Customer Services be contacted in advance of its return so that a Return Authorization Number can be assigned to the unit Also ORTEC must be informed either in writing by telephone 865 482 4411 or by facsimile transmission 865 483 2133 of the nature of the fault of the instrument being returned and of the model serial and revision Rev on rear panel numbers Failure to do so may cause unnecessary delays in getting the unit repaired The ORTEC standard procedure requires that instruments returned for repair pass the same quality control tests that are used for new production instruments Instruments that are returned should be packed so that they will withstand normal transit handling and must be shipped PREPAID via Air Parcel Post or United Parcel Service to the designated ORTEC repair center The address label and the package should include the Return Authorization Number assigned Instruments being returned that are damaged in transit due to inadequate packing will be repaired at the sender s expense and it will be the sender s responsibility to make claim with the shipper Instruments not in warranty shoul
73. twork Eight lines 0101 0108 are used for the transfer of data between the components of the system Three lines DAV NRFD and NDAC are used as transfer control The remaining five lines IFC ATN SRQ HEN and EOI are for bus management These lines may employ either open collector or tri state drivers as defined by the IEEE 488 1978 standard Information is transmitted over the eight data lines under direct supervision of the three transfer control lines Transfer proceeds as fast as the components of the system can respond but no faster than the slowest device currently addressed by the bus This permits multiple data transfers to more than one device on the bus at a time Active devices connected into the system may be talkers listeners controllers or a combination of the three but no more than one device may be designated as a talker at any given time The controller determines the role of each of the devices by sending out an address of the device to be defined Addresses of the devices are set at the time of system configuration before power is applied by means of an 8 position DIP switch Sections 1 thru 5 of switch 1 are used for the address selection Table 5 Table 5 Address Configuration Switch _ Position Off 7 On 1 Address 1 Address 0 2 Address 2 Address 0 3 Address 4 Address 0 4 Address 8 Address 0 5 Address 16 Address 0 6 Recycle Mode One Cycie Mode 7 Counter Timer Coun
74. ues for Delay properly A 6 CATALOG OF COMMANDS FOR THE 994 The commands on the following pages are arranged in alphabetical order Be sure to read the introductory material in this appendix before proceeding to the command descriptions Command CLEAR_ALL CLEAR_COUNTERS CLEAR_COUNT_PRESET CLEAR EVENT PRESET COMPUTER DISABLE_ALARM DISABLE_EVENT DISABLE EVENT PRESET DISABLE_TRIGGER_START DISABLE_TRIGGER_STOP ENABLE ALARM ENABLE EVENT AUTO ENABLE EVENT PRESET ENABLE_LOCAL ENABLE_REMOTE ENABLE_TRIGGER_START ENABLE_TRIGGER_STOP INIT SET COUNT PRESET lt MN P gt 30 Minimum Letters CL_ALL CL_COU CL_COU_PR CL_EV_PR COMP DIS_ALA DIS_EV DIS_EV_PR DIS TRILSTART DIS TRI STOP EN_ALA EN_EV_AU EN_EV_PR EN_LOC 5 EN_TRILSTO INIT SET_COU_PR CATALOG OF COMMANDS Description Clears counters count preset event counter and event preset Clears all counters in the 994 module Clears the M N and P values in the 994 Resets the event preset register to zero Sets the 994 to the computer mode where it does not echo any characters Thisis the complement to the TERMINAL command Disables the alarm function When the alarm is disabled the 994 does not auto matically send the contents of the counters to the host computer when the preset count value is reached The front panel Dwell control is enabled and the 994 o

Model 994 Dual Counter/Timer Operating and Service Manual

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