C:\Software Manuals (Keyser)\783530E TRUMP-PCI.wpd
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1. An optional checksum may be added to the end of any command sent to an MCB The checksum is a 1 byte unsigned integer sum of all of the characters in a command treated as unsigned integers up to and including the comma or space s that separates the checksum from the 13 TRUMP PCI 8K 2K Multichannel Buffer Card command The checksum simply appears as an extra parameter added to the end of the command parameter list For commands that do not normally have parameters the checksum appears as the only parameter separated from the header by one or more spaces All optional parameters must be included in a command if a checksum is to be provided so that the checksum is not mistaken by the MCB as a parameter For example the SET_WINDOW command must include the two optional parameters start and length if the checksum is provided e g SET WINDOW 0 8192 159 5 2 Percent Response Records TRUMP PCI cards respond to all commands with a percent response record that signifies the completion of the command Percent response records contain two error code numbers and a 1 byte checksum as follows aaabbbccc CR where represents the ASCII character aaa represents the macro error code bbb represents the micro error code ccc represents the checksum and CR represents the ASCII carriage return character signifying the end of the record The macro error code represents the general class of error with 0 meaning no error and the micro2. Beginning of 3rd word 0 64 External dwell support ENA DIS_DWELL_EXT 0 65 Selectable SUM or REPLACE MCS modes ENA DIS_SUM 66 External start of pass is set with ENA DIS_START_EXT 67 MCS list commands present LIST_ULSCA LIST_LLSCA LIST_SOURCE 68 MDA Preset 69 Programmable external ADC Type 0 70 Programmable printer port daisy chain ENAB_DAIS SHOW_GAIN_CONVERSION This command returns the conversion gain Responses C00512095 lt CR gt Conversion gain reported as 512 channels C01024094 lt CR gt Conversion gain reported as 1024 channels C02048101 lt CR gt Conversion gain reported as 2048 channels C04096106 lt CR gt Conversion gain reported as 4096 channels 8K only C08192107 lt CR gt Conversion gain reported as 8192 channels 8K only SHOW_GATE Reports the current mode of operation of the ADC gate input See also SET_GATE_OFF SET_GATE_COINCIDENT and SET_GATE_ANTICOINCIDENT Responses FOFF lt CR gt Reports the ADC gate is off or ignored FCOI lt CR gt Reports the ADC gate is in coincident mode FANT lt CR gt Reports the ADC gate is in anticoincident mode SHOW INTEGRAL start chan number of chans Reports the sum of the specified group of spectral data channels If start chan and number of chans is not provided SHOW INTEGRAL reports the sum of all channels that have their ROI flag set 26 5 COMMANDS AND RESPONSES Responses G0000000000075 lt CR gt Integral reported as 0 G429496
3. TRUMP PCI 8K 2K Multichannel Buffer Card PRESET A limit set for a clock or region of interest count that if exceeded during an acquisition will cause the acquisition to stop TRUMP PCIS have live time true time ROI integral ROI peak overflow MDA and peak uncertainty presets for each device in the MCB PROGRAM MEMORY The flash memory on the TRUMP PCI card that contains the microprocessor instructions and fixed data for controlling the operation of the MCB RAM Random access memory RECORD A sequence of related bytes TRUMP PCI command percent and dollar records are composed of printable ASCII characters and end with an ASCII carriage return ROI CHANNEL A channel that has the region of interest ROT flag set ROI FLAG A set of internal MCB flags one for each channel which when set identifies the channel as being part of the region of interest All channels in a device that have the ROI flag set are considered when ROI integral or ROI peak presets are evaluated SEGMENT A subdivision of a device Segments are not implemented on TRUMP PCIS and are referenced only for compatibility with other MCBs TICK The minimum unit of time associated with a clock such as the real time or live time clocks a clock tick TRUE TIME The actual time that data acquisition is active regardless of the MCB s ability to process detector pulses True time is also known as real time WINDOW OF INTEREST The continuous group of channels
4. Dsssssnnnnncec lt CR gt where sssss represents an integer number that is the number of the first channel of the first group of channels that all have their ROI bit set and nnnnn represents an integer number that is the number of channels in the group The SHOW_NEXT command is used to report the next group of channels that all have their ROI bit set Responses D0100000050078 lt CR gt First ROI group starts at channel 1000 and is 50 channels long D0215000150086 lt CR gt First ROI group starts at channel 2150 and is 150 channels long D0000000000072 lt CR gt No ROI groups to report SHOW_ROI_MDA Reports the start channel and number of channels used in the MDA preset calculation Example Response D0700000050ccc Calculation is performed on channels 7000 7049 30 5 COMMANDS AND RESPONSES SHOW_ROI_UNCERTAINTY Reports the start channel and number of channels used in the uncertainty preset calculation See also SET ROI UNCERTAINTY Response D0700000050ccc SHOW SNUM Calculation is performed on channels 7000 7049 Returns an F record and the serial number of the TRUMP PCI See SET SNUM Responses F115 SHOW STATUS TRUMP PCI serial number is 115 In PHA mode returns system status information in the following format Mimillllittttttttttaaaaahhhhhccce CR where IM represents the live time as returned by the SHOW LIVE command tttttttttt represents the true time as returned by the
5. TRUMP PCI commands contain a command header which may be followed by numeric parameter values The header consists of a verb or a verb and noun separated by an underscore or a verb noun and modifier each separated by underscores The verbs nouns and modifiers in the command header are mnemonic words such as the verb ENABLE or the noun OVERFLOW that relate to the function performed by the MCB when it executes the command The first four letters of any word will always be enough to uniquely identify the word when composing commands for an MCB For example the command ENABLE OVERFLOW PRESET can be abbreviated to ENAB OVER PRES Numeric parameters are unsigned integer numbers that follow the command header separated by one or more spaces Specific commands require up to three parameters separated by commas which specify numeric quantities related to the operation of the MCB such as live time or conversion gain The command SET WINDOW 0 8192 has two parameters 0 and 8192 which set the window of interest to start at channel 0 and continue for 8192 channels Some parameters listed in the command dictionary are considered optional and are distinguished from mandatory parameters by being surrounded by brackets in the command prototype line e g SET WINDOW start length Commands that have optional parameters may be sent to the MCB without the optional parameters in which case the behavior will be changed as explained in the command description
6. in MAESTRO 3 8 Troubleshooting Battery Backup FailedThe memory in the TRUMP PCI has battery backup to maintain data when power is turned off The battery is a lithium battery with a nominal voltage of 3 V The battery is located on the top left corner of the TRUMP PCI card see Fig 1 It may be necessary to bend the battery holder down after removing the old battery to get good contact with the new battery Battery Specification Type Lithium Coin Cell Model Panasonic CR 2354 ORTEC Part Number 739480 4 MCA BASICS This chapter contains some basic information about MCAs ORTEC has taken the classical MCA and partitioned it into two components an MCB and a PC The MCB contains the circuitry required to create a spectrum while the personal computer is used for display of the spectrum and control of the instrument The first half of this section describes the circuitry found on the TRUMP PCI MCB while the second half describes the dead time effects encountered in an MCA 4 1 MCB Operation This section contains a very basic description of the input circuitry and the chain of events that occurs in the TRUMP PCI card when an input pulse arrives to be histogrammed Figure 3 shows the basic block diagram of the input section of the TRUMP PCI MCB First a description of each block in the circuit PH Analog to Digital Stretcher qa Linear Gate Converter Zero Level Lower Leve
7. Next ROI group starts at channel 1000 and is 50 channels long D0215000150086 lt CR gt Next ROI group starts at channel 2150 and is 150 channels long D0000000000072 lt CR gt No other ROI groups to report 28 5 COMMANDS AND RESPONSES SHOW_OFFSET_FINE Returns the current ADC offset Example Responses C02048101 Offset is 2048 hardware units or 0 channels C00000087 Offset is O hardware units or 140 channels SHOW_OVERFLOW_PRESET Reports the state of the overflow preset Responses IT lt CR gt Overflow preset enabled IF lt CR gt Overflow preset disabled SHOW_PEAK This command returns the contents of the ROI channel with the largest number of counts An ROI channel is a channel that has the ROI flag set The maximum possible value is 2147483647 which is the maximum number of counts that can be stored in a 31 bit channel Responses G0000000000075 lt CR gt Maximum count in an ROI channel is zero or no ROI channels were found G0000000001076 lt CR gt Maximum count in an ROI channel is 1 G2147483646120 lt CR gt Maximum count in an ROI channel is 2147483646 G2147483647121 lt CR gt Maximum count in an ROI channel is 2147483647 SHOW_PEAK_CHANNEL This command returns the number of the ROI channel with the largest number of counts An ROI channel is a channel that has the ROI flag set The lowest number ROI channel with the largest count is reported if more that one channel contains the largest number
8. TRUMP PCI cards can be controlled from the same PC under one copy of MAESTRO 32 with no overhead on the PC resources During data acquisition the computer is entirely free to run other tasks A large number of ORTEC software applications support the TRUMP PCI and developer s toolkits are also available 1 1 Using the Manual This manual discusses the initial setup and installation of the TRUMP PCI 8K 2K card For instructions on installing and operating MAESTRO 32 refer to the MAESTRO 32 Software User s Manual Chapter 1 of this manual gives a brief description of the TRUMP PCI MAESTRO 32 system Chapter 2 gives the TRUMP PCI card specifications Chapter 3 tells how to set up and install the TRUMP PCI card Chapter 4 describes the basics of MCA operation Chapter 5 explains the commands used to control the system for users who wish to write custom software to control the TRUMP PCI card TRUMP PCI 8K 2K Multichannel Buffer Card 2 SPECIFICATIONS 2 1 Performance ADC Successive approximation type with sliding scale linearization Resolution Software selectable as 512 1024 and 2048 for the TRUMP PCI 2K with addition choices of 4096 and 8192 for the TRUMP PCI 8K Dead Time Per Event 9 Us including memory transfer Use the SET_RESET_DELAY and SHOW RESET DELAY commands to decrease to a minimum of 8 Us or increase system dead time see Section 5 4 Integral Nonlinearity lt 0 025 over the top 99 of the dynamic range Differ
9. affected by commands like CLEAR and SET DATA The window of interest is set by the SET WINDOW command as well as by the SET DEVICE and SET SEGMENT commands 36 INDEX ADC gale x UR oto 19 26 ADC LLED 2 ous edic ee Dane dh dee at 4 PIS Fen ee een 4 Analog to Digital Converter 10 Battery Aa uterque aen dede 8 BUSY o ee EORR UAR RUN 4 Command Catalog 16 Conversion gain ele lee e e e eee a 18 Dead Time nein a RM UR 3 10 Differential Nonlinearity 3 Firmware version ani eee Uo ra ee x 33 Gate Smet ere Le 4 8 Crede ke Hale c ee ne e ee 5 11 Installations rS C ae ate RR 6 GSS ety stars an ne are regen 27 Integral Nonlinearity 3 Intestalpresei ac sta Bein 21 Linear Gate oam und nn edo Bec edo enc 9 PELO ee HC PER E 16 OvVertlow preset SA 17 29 PEAK asus ee ea 29 Peak Channel 29 Peak Streicher setae cs eux iris ate 9 POWER aA 4 gi 3 PUR E 4 Region of interest se sais e ut 17 RESET ans rar Eb ERE 18 Re sol tiorn 45055 ee 3 Response Records oes ve uS RA 14 ROD see 28 ee 21 DEG viec ae tios ae nd entes 16 VEISION ausi ane dis dir wala ME aa Se dee SIR 33 Window of interest 16 Zero XdTUs uie HE ee 8 37 TRUMP PCI 8K 2K Multichannel Buffer Card 38
10. enabled see ENABLE_ALARM command See also DISABLE_OVERFLOW_PRESET and SHOW_OVERFLOW_PRESET commands INITIALIZE Resets the TRUMP PCI hardware and software as though the following commands have been issued STOP SET_WINDOW 0 8192 SET_GATE_OFF CLEAR_ALL SET GAIN CONVERSION 0 This completely clears all settings as if the backup battery has failed Execution Errors The INITIALIZE command simulates a power down power up cycle for the MCB after a simulated loss of battery backed up memory 17 TRUMP PCI 8K 2K Multichannel Buffer Card LIST_OFFSET_FINE Returns the minimum and maximum ADC offset settings in real world units channels and the integer realization that will actually be used in the SET_OFFSET_FINE command Response OFFSET_FINE 140 40 0 4095 The offset will be 140 channels when the SET OFFSET FINE 0 command is issued and 140 channels when the SET OFFSET FINE 4095 command is issued All other settings will have a linear relationship to these two endpoints RESET Resets the TRUMP PCI card to the state just after power is applied applying the settings saved by the battery backup SET DATA count Sets all channels of spectral data in the window of interest see SET WINDOW command for the currently selected device see SET DEVICE command to the specified count ROI flags are not affected SET DEVICE device Makes the specified device the currently selected device and remaps shared data memory so that
11. error code represents the sub class of error with 0 meaning no error The following table lists all percent responses for a TRUMP PCI Unconditional Success 96000000069 No errors detected START STOP Warnings 20000005074 MCB already started or stopped 20000006075 Preset already exceeded Command Syntax Errors 129001082 Invalid verb in command 129002083 Invalid noun in command 129003084 Invalid verb and noun in command 129004085 Invalid modifier in command 129005086 Invalid verb and modifier in command 129006087 Invalid noun and modifier in command 129007088 Invalid verb noun and modifier in command 129132087 Invalid command verb noun and modifier valid but not together 14 Communication Errors 130128084 130129085 Execution Errors 131128085 131129086 131130078 131132080 131135083 131136084 5 COMMANDS AND RESPONSES Incorrect checksum only if checksum provided Command record too long Invalid 1st parameter Invalid 2nd parameter Invalid 3rd parameter Invalid number of parameters Illegal command while acquisition is in progress Illegal command in current mode of operation 5 3 Dollar Response Records SHOW commands respond with a single dollar response record followed immediately by a percent response record All valid dollar response records for each command are listed in the command dictionary The following table lists the general form of each dollar response record for
12. from 0 to 10 V 12 V maximum semi Gaussian shaped or gated integrator shaped time constants from 0 25 to 30 Us or delay line shaped with width gt 0 25 us Za 1 dc coupled No internal delay BNC connector on rear panel GATE ADC gate Optional slow positive NIM input Computer selectable coincidence or anticoincidence Signal must occur prior to and extend 0 5 Ws beyond the peak of the pulse rear panel BNC connector Z 1 PUR Pile up rejection input accepts slow positive NIM signal signal must occur prior to peak detect Z 1 KQ BNC connector on rear panel BUSY Busy input used by live time correction circuits Accepts slow positive NIM signal signal must occur prior to peak detect Za 1 BNC connector on rear panel 2 4 Electrical and Mechanical Power Required 5 V 1 5 A Dimensions Standard full slot PCI card 2 5 Software Prerequisites MAESTRO 32 runs on any PC that supports Windows 95 Window 98 or Windows NT 3 INSTALLATION This chapter tells how to set up a standard TRUMP PCI system Section 3 1 shows how to select extended or simple live time correction mode Section 3 2 describes how to install the TRUMP PCI card Section 3 3 discusses multiple MCB systems Section 3 4 contains the cabling requirements for a standard detector system Sections 3 5 and 3 6 tell how to adjust the lower and upper level discriminators and the zero adjustment Section 3 7 describes the Gate Input Section 3 8 c
13. from any command in practice these error responses rarely occur on systems with reliable communication hardware running debugged software Refer to Section 5 2 for information about error responses In the following catalog the commands are listed in alphabetical order each starting with a command prototype line Uppercase letters numeric digits blank space and special symbols such as the underscore and comma in the prototype line are literal text to be sent to the MCB exactly as it appears Lowercase letters in the prototype line represent numeric values as described in the accompanying text and should not be sent literally to the MCB but should be replaced by an appropriate numeric value Items in the command prototype that are surrounded by brackets are optional items and are not always required In this section the term CR represents the ASCII carriage return character decimal value 13 and the character represents the ASCII underscore character decimal value 95 CLEAR The channels of spectral data in the window of interest see SET WINDOW command are set to zero The live time and true time counters are also set to zero This command is equivalent to the combination of CLEAR COUNTERS and CLEAR DATA commands CLEAR ALL This command is equivalent to the combination of CLEAR COUNTERS CLEAR DATA CLEAR PRESETS and CLEAR ROI commands Execution Errors 131135083 lt CR gt The command was attempt
14. instrument must pass a stringent 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 Instrument
15. of i in channels SET UNCERTAINTY PRESET percent Sets the uncertainty preset to the specified value in percent percent is a floating point value from 0 99 9999 See also SHOW UNCERTAINTY PRESET Execution Errors 131128085 lt CR gt The value is incorrect 131132080 lt CR gt A value must be included SET WINDOW start length Sets the window of interest to the specified start channel and number of channels The channels of spectral data in the window of interest are affected by commands such as CLEAR and SET DATA If neither start or length is provided the window is set to the maximum size allowed by the conversion gain specified for the currently selected device The window of interest is always set to the maximum size after a SET DEVICE command or a SET SEGMENT command Execution Errors 131128085 lt CR gt The start channel was too high for the conversion gain 131129086 lt CR gt The length specified one or more channels that were too high for the currently selected device s conversion gain 131132080 lt CR gt The start channel was specified without a length If one value is given the other must be also given SHOW_ACTIVE Returns a 1 if the ADC is active acquiring spectral data or 0 if it is not active Responses C00000087 CR The ADC is not active C00001088 lt CR gt The ADC is active SHOW_ADC_CONVERSION This shows the channel value for the last conversion by the ADC as a C record SHOW_CONFIGURATION Re
16. state of the ADC gate input signal See the section on the ADC gate input for more information See also SET COINCIDENT SET GATE ANTICOINCIDENT and SHOW GATE SET INTEGRAL PRESET count Sets the ROI integral preset to the specified count During data acquisition when the sum of the counts contained in the channels of a device that have the ROI flag set reaches the integral preset count the preset is complete and the acquisition is stopped The actual number of counts in the ROI integral may exceed the preset value by up to 512 counts due to the pipelined architecture of the TRUMP PCI card Setting an integral preset to 0 counts disables the preset The integral preset may be set to from 0 disabled to 4294967295 counts See also CLEAR PRESETS and SHOW INTEGRAL Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET_LIVE ticks Sets the live time counter for the currently selected MCB to the specified number of ticks The number represents live time in units of 20 ms 50 ticks per second Normally this value is set by the TRUMP PCI during data acquisition See also CLEAR_COUNTERS and SHOW_LIVE Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET_LIVE_PRESET ticks Sets the live time preset to the specified number of ticks 20 ms During data acquisition when th
17. 7294131 lt CR gt Integral reported as 4294967294 G4294967295132 lt CR gt Integral reported as greater than or equal to 4294967295 maximum reportable value SHOW_INTEGRAL_PRESET Reports the current ROI integral preset value See SET_INTEGRAL_PRESET for more information about the ROI integral preset See also SHOW INTEGRAL Responses G0000000000075 lt CR gt Integral preset reported as 0 G4294967295132 lt CR gt Integral reported as 4294967295 SHOW_LIVE Reports the contents of the live time counter in units of 20 ms 50 ticks per second See also CLEAR_COUNTERS and SET_LIVE Responses G0000000000075 lt CR gt Live time reported as O ticks G0000000001076 CR Live time reported as 1 tick 20 ms G4294967295132 CR Live time reported as 4294967295 ticks over 23000 days SHOW LIVE PRESET Reports the current live time preset in units of 20 ms 50 ticks per second See also CLEAR PRESETS and SET LIVE PRESET Responses G0000000000075 lt CR gt Live time preset reported as disabled G0000000001076 lt CR gt Live time preset reported as 1 tick G4294967295132 lt CR gt Live time preset reported as 4294967295 ticks SHOW_LIVE_REMAINING This returns the live time remaining until the live time preset is reached The number of 20 ms ticks is returned in a G record SHOW_LLD This returns the lower level discriminator setting in channels as a C record See also SET_LLD 27 TRUMP PCI 8K 2K Multichan
18. ORTEC TRUMP PCI 8K TRUMP PCI 2K Multichannel Buffer Card Hardware Manual Printed in U S A ORTEC Part No 783530 4314 0502 Manual Revision E Advanced Measurement Technology Inc a k a ORTEC a subsidiary of AMETEKS 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
19. PC then press the card gently and firmly into the slot connector 4 Fasten the card to the chassis with the option slot cover screw 5 Replace the computer cover 6 The TRUMP PCI card uses a driver for communication with Windows The driver file is supplied on floppy disk To install the driver in Windows 95 98 install the card restart the PC and allow Windows to autodetect the new hardware When Windows asks for the driver browse the floppy disk for the file PcITrump ini via a label and click on OK In Windows NT and when autodetect does not work use Start Settings Control Panel Add New Hardware to install the driver 3 3 Setting Up a Multiple MCB System Up to eight ORTEC MCBs in any combination can be attached at one time to a single PC To prevent conflicts in multiple MCB systems each MCB must be assigned a unique hardware address This is done automatically in TRUMP PCI cards so there are no jumpers or DIP switches for you to set However other types of MCBs may still require you to set jumpers or DIP switches follow the instructions in the corresponding hardware manuals 3 4 Cabling a System The standard cabling of a TRUMP PCI card in a HPGe detector system is shown in Fig 2 If the detector has a TRP preamplifier PLUS model all connections shown should be made If the preamplifier is a resistive feedback preamplifier the INHIBIT OUTPUT does not exist so the connection to INHIBIT is not made INHIBIT is lef
20. SHOW TRUE command aaaaa represents the active device mask as returned by the SHOW ACTIVE DEVICES command and hhhhh represents the hardware status which is an ASCII representation of a 16 bit decimal number with the following bit definitions Bit 0 LSB Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7 Bit 8 Bits 9 Bit 10 Bit 11 Bit 12 Bit 13 Bit 14 Bit 15 MSB Bias supply polarity 0 positive 1 negative Bias supply overload 0 overload 1 normal HV enabled 0 disabled 1 enabled Unused Amplifier PZ d since initialization 0 2 normal 1 2 needs PZ ing Unused Waiting for MCS to finish current sweep after STOP command 0 normal 1 waiting for completion Unused Amplifier automatic PZ 0 normal 1 Auto PZ in progress Unused Power conservation mode 0 full power 1 conservation Waiting for start delay 0 ready 1 waiting Main Battery 2 In Use 0 battery 1 in use 1 battery 2 in use Main Battery 1 Low Warning 0 normal 1 battery voltage low Main Battery 2 Low Warning 0 normal 1 battery voltage low Unused 31 TRUMP PCI 8K 2K Multichannel Buffer Card In MCS mode returns system status information in the form Mppppppppppcccccceccccaaaaahhhhhecc where pppppppppp is the pass count as returned by SHOW PASS command is the current channel as returned by SHOW CHANNEL aaaaa and hhhhh are the same as in PHA mode and ccc is the
21. a TRUMP PCI MCB In this table lowercase letters represent numeric values The letters cee always represent an 8 bit unsigned checksum of all characters on the record up to but not including the checksum characters and CR represents the ASCII carriage return character Response Axxxccc Cxxxxxccc Dxxxxxyyyyyccc Exxxxxccc Fsssss GXXXXXXXXXXCCC SIT IF Jxxxxxyyyyy ccc MXXXXXXXXXX CCC Nxxxyyyzzzccc Description xxx is an 8 bit unsigned number Xxxxxx is a 16 bit unsigned number xxxxx and yyyyy are 16 bit unsigned numbers xxxxx is a 16 bit alarm mask SSSS is a variable length ASCII character sequence No checksum is sent with this record XXXXXXXxxx s a 32 bit number True response to a SHOW command no checksum False response to a SHOW command no checksum Response to SHOW_CONFIG command Response to SHOW_STATUS command XXX yyy and zzz are 8 bit unsigned numbers 15 TRUMP PCI SK 2K Multichannel Buffer Card 5 4 Command Catalog This section lists each TRUMP PCI command with a description of its operation The descriptions include a list of any unusual responses that may result As described in previous sections the usual response from a command is a 000000069 lt CR gt response which represents a macro error code of 0 and a micro error code of 0 no errors All execution error responses if any are listed for each command Though syntax and communication error responses may result
22. annel Buffer Card 34 APPENDIX A GLOSSARY ACQUISITION The process of collecting data from a detector and storing the data in memory ASCH American Standard Code for Information Interchange The ASCH code is defined by ANSI American National Standards Institute standard X3 4 1977 This standard describes the representation of characters as 8 bit binary numbers This representation for characters is used by most mini and personal computers CHECKSUM The sum of bytes in a record used to detect when communication errors occur CLOCK A component of a device that keeps track of some form of time TRUMP PCI MCBs have live time and true time clocks COUNTER Another name for a TRUMP PCI clock live time or true time DEAD TIME The time that data acquisition is active but the MCB cannot process detector pulses is dead Dead time for a device is equal to the true time minus the live time DEVICE The entity within an MCB that collects and stores spectral data A device corresponds to the MCB s inputs Model 919 MCBs have 4 inputs and thus 4 devices while TRUMP PCIs have only 1 input and thus 1 device A device can be selected started stopped and cleared HOST The computer that sends commands to an MCB and receives responses from the MCB LIVE TIME The time that data acquisition is active and the MCB is capable of processing detector pulses is live Live time for a device is equal to the true time minus the dead time 35
23. checksum SHOW TRUE Reports the contents of the true time counter in units of 20 ms 50 ticks per second See also CLEAR COUNTERS and SET TRUE Responses G0000000000075 lt CR gt True time reported as O ticks G0000000001076 CR True time reported as 1 tick 20 ms G4294967295132 CR True time reported as 4294967295 ticks over 23000 days SHOW TRUE PRESET Reports the current true time preset in units of 20 ms 50 ticks per second See also CLEAR PRESETS and SET TRUE PRESET Responses G0000000000075 lt CR gt True time preset reported as disabled G0000000001076 lt CR gt True time preset reported as 1 tick G4294967295132 lt CR gt True time preset reported as 4294967295 ticks SHOW_TRUE_REMAINING This returns the true real time remaining until the real time preset is reached The number of 20 ms ticks is returned in a G record SHOW_ULD This returns the value of the upper level discriminator in channels as a C record SHOW_UNCERTAINTY Returns the current value of the uncertainty for the peak in the uncertainty preset See also SET_UNCERTAINTY Responses UNCE 0000000000008 5 Uncertainty of the peak is 8 5 32 5 COMMANDS AND RESPONSES SHOW_UNCERTAINTY_PRESET Returns the current uncertainty preset setting See also SET_UNCERTAINTY_PRESET Responses UNCE_PRES 000000000000000 No preset UNCE_PRES 0000000000008 5 Preset set to 8 5 SHOW_VERSION Reports the firmware version number in the f
24. conditions are satisfied The ADC conversion and readout is complete The ADC input has returned below the LLD threshold The PUR and BUSY signals have returned to the inactive state 11 TRUMP PCI 8K 2K Multichannel Buffer Card Turning off the live time clock compensates for the probability of losing a second pulse during the processing of the first pulse Subtracting live time compensates for the probability of losing two pulses when the second pulse distorts the amplitude of the first pulse 12 5 COMMANDS AND RESPONSES This chapter is intended for users who wish to write custom software to control the TRUMP PCI card For more information see the MAESTRO 32 Software User s Manual or the ORTEC Universal MCB Interface UMCBI Toolkit A11 B32 Communication with a TRUMP PCI card consists of sending command records to the MCB and receiving response records from the MCB The records consist of a sequence of printable ASCII characters followed by an ASCII carriage return All commands eventually respond with a percent response record so named because it begins with an ASCII percent sign which signifies the completion of the command SHOW commands respond with a dollar response record begins with an ASCII dollar sign followed by a percent response record All characters up to the first carriage return or the end of the message are considered to be part of a command to the MCB 5 1 Command Records
25. de SCA input available MCS mode TTL input available MCS mode fast neg NIM input available MCS mode discriminator input available Switchable MCS mode discriminator edge TRUMP PCI oO OH r Bit 41 42 43 44 45 46 47 48 49 50 51 52 33 54 55 56 57 58 39 60 61 62 63 5 COMMANDS AND RESPONSES Meaning Programmable MCS mode discriminator level Programmable SCA Software selectable MCS mode input sources Statistical preset SET_UNCERT_PRES Features vary by input multi input MCBs only Software selectable HV shutdown SET SHOW VERI_SHUT Software selectable shaping time SET_SHAP Explorable shaping time SHOW_CONF_SHAP Advanced shaping time SET_SHAP_RISE etc Software settable BLR ENA_BLR_AUTO etc SHOW_STATUS command supported with M response Overflow preset ENA DIS SHO_OVER_PRES MicroNOMAD style clicker ENAB_CLICK DISA_CLICK etc Thermistor support SHOW THERM Floating point fine gain SET SHOW GAIN FINE Settable PUR PUR SET WIDT VERI WIDT REJ Alpha style HV PS SHOW HV CURR Readable vacuum SHOW VACUUM Acquisition alarm ENA DIS SHO ALARM Hardware acquisition trigger ENA DIS SHO TRIG Ordinal numbers accepted for SET SHAP Explorable gains LIST VERI GAIN FINE COAR CONV Routable inputs SET SHOW INPUT ROUTE 25 TRUMP PCI 8K 2K Multichannel Buffer Card TRUMP PCI Bit Meaning
26. e live time counter reaches the preset number of ticks the preset is complete and the acquisition is stopped Setting a live time preset to 0 ticks disables the preset See also CLEAR PRESETS and SHOW LIVE PRESET 19 TRUMP PCI 8K 2K Multichannel Buffer Card Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET LLD x This sets the lower level discriminator to the value x specified in channels SET MDA COEF a b c Sets the coefficients in the MDA preset calculation to the specified values A b and c are floating point values The MDA preset stops the calculation when the following condition is met MDA Preset gt 2 X CountsinROT Live Time The MDA preset calculation is performed once per minute SET MDA PRESET preset Sets the MDA preset to the specified value The preset is the product of the desired MDA the efficiency and the yield SET OFFSET FINE offset Changes the ADC offset Offset is a value from 0 to 4095 When offset is zero an offset of approximately 140 channels at 8192 conversion gain is applied When offset is 2048 shift is applied to the spectrum SET PEAK PRESET count Sets the ROI peak preset to the specified count During data acquisition when the contents of any channel of a device that has the ROI flag set reaches the peak preset count the preset is complete and the acquisition is stopped The actual numb
27. ed while spectrum acquisition was in progress No action was taken CLEAR_COUNTERS The live time and true time counters are set to zero CLEAR_DATA The channels of spectral data in the window of interest see SET_WINDOW command The ROI flags are not changed nor are the presets changed 16 5 COMMANDS AND RESPONSES CLEAR_PRESETS The live time true time ROI integral ROI peak and overflow presets are all set to zero disabled Execution Errors 131135083 The command was attempted while spectrum acquisition was in progress No action was taken CLEAR_ROI The region of interest flags for the channels in the window of interest see SET WINDOW command are cleared Execution Errors 131135083 The command was attempted while spectrum acquisition was in progress No action was taken DISABLE_OVERFLOW_PRESET Disables the overflow preset Channels that receive a count when they contain 2147483647 counts the maximum number of counts will roll over to zero counts if the overflow preset is disabled See also ENABLE_OVERFLOW_PRESET and SHOW_OVERFLOW_PRESET ENABLE_OVERFLOW_PRESET Enables the overflow preset Channels that receive a count when they contain 2147483647 counts the maximum number of counts will stop the acquisition for that channel s device if the overflow preset is disabled The channel that caused the preset to complete will contain 2147483647 counts An alarm response record will be sent to the host if alarms are
28. ential Nonlinearity lt 1 over the top 99 of the dynamic range Gain Instability lt 50 ppm C Dead Time Correction Printed wiring board jumper selects either extended live time correction according to the Gedcke Hale method or simple live time correction with the clock turned off during the conversion time Data Memory 8K channels of battery backed up memory 2 1 counts per channel over 2 billion Presets Real Time Live Time Multiples of 20 ms Region of Interest Peak count Integral count Data Overflow Terminates acquisition when any channel exceeds 2 1 Peak Uncertainty Stops acquisition when the statistical or counting uncertainty of a user selected net peak reaches the specified value Nuclide MDA Stops data collection when the value of the Minimum Detectable Activity MDA for a user specified MDA nuclide reaches the specified value Microprocessor Intel 386 32K x 16 RAM with battery backup 4 Mbit flash memory Ron Jenkins R W Gould and Dale Gedcke Quantitative X Ray Spectrometry New York Marcel Dekker Inc 1981 pp 266 267 TRUMP PCI 8K 2K Multichannel Buffer Card 2 2 Controls ADC Zero Computer controlled 125 mV ADC LLD Computer controlled from 0 to 100 full scale ADC ULD Computer controlled from 0 to 100 full scale 2 3 Inputs IN Input Accepts positive unipolar positive gated integrator or positive leading bipolar analog pulses in the dynamic range
29. er of counts in the ROI peak may exceed the preset value by a small number of counts due to the pipelined architecture of the TRUMP PCI card Setting a peak preset to 0 counts disables the preset The peak preset may be set to from O disabled to 2147483647 counts See also CLEAR PRESETS and SHOW PEAK PRESET Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET_RESET_DELAY delayticks Inserts dead time into the system between the completion of one acquisition cycle and the beginning of the search for a new pulse and adds to the TRUMP PCT s 8 us minimum dead 20 5 COMMANDS AND RESPONSES time Delayticks represents the amount of time added 1 delaytick 80 ns The default value for delayticks is 20 1 2 Us of delay resulting in a default dead time of 9 2 us and can set anywhere between 1 and 2x10 1 Setting the reset delay to zero results in no pulse essentially an infinite delay This delay is needed only when the stretcher capacitor has not had enough time to completely discharge in which case double peaking might be observed In these instances the delay should be needed only with input pulses less than 2 Us in width Consequently for systems using a 2 Us input pulse the reset delay can be set to 1 Example SET RESET DELAY 1 Add 80 ns to the reset delay so total reset delay 8 08 us SET ROI start chan number of chans Sets
30. isiles u te ehe eR o SCR efus oe oe de Che de Ren 4 SAC INSTALLATION a etel qct iab dom ee ee D b berg co i nh 5 oily Lives Time Mode sn a EIER BER WEAR dd 5 3 2 Installing the TRUMP PEI Card Cen ob ba ee Ween ee oe ves 6 3 3 Setting Up a Multiple MCB System 22 nn ata eee eee eee 6 32 Cablins a Systems zuo Se EEE HENRIETTE EN ESF EL 6 3 5 Adjusting the Lower and Upper Level Discriminators 7 Su Settins he Zero Adjustment os rore tee ient tg ne te e x dete ores 8 3 7 Enabling the Crate dues roses duse ss d en d d esu 8 3 8 Troubl sh otins seco ues Cre e nr tee vet ee eae Rs 8 4 MCA BASICS DPI een ee 9 4 1 MCB Operation aaa dag sr en es bn ee Howe Mesa eee 9 4 2 Dead Time in MCA and Amplifier 2 504 I re ie ES 10 COMMANDS AND RESPONSES 21 5 RO dn re Ob ete 13 OMANI BeCcoldou sev isa es ees tO on tr Kos dev ees 13 5 2 Percent Response Records sede sonda iae TURNS Re WALA ce A d 14 3 3 Dollar Response Records 2302042 yE 15 SA Command Gk ose Pe 16 APPENDIX A GLOSSARY sores dir ar Er Era Ue 35 INDEK SRE A 37 iii 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 othe
31. l Upper Level Discriminators Data Ready Figure 3 TRUMP PCI Input Block Diagram Buffer The buffer is provided to properly match impedances between the input and the TRUMP PCI circuitry Linear Gate The linear gate protects the peak stretcher during conversion of an event When the linear gate is open its output is identical to its input When the linear gate is closed its output is always zero Peak Stretcher The peak stretcher operates in one of two modes Track or Hold In Track mode the output of the peak stretcher is identical to its input In Hold mode the peak stretcher acts like a maximum function It outputs the maximum value which is applied to the input The peak stretcher also has a peak detect output which goes active when its output is greater than the value at its input TRUMP PCI 8K 2K Multichannel Buffer Card Analog to Digital Converter ADC The ADC takes an analog signal and converts it to a digital equivalent Zero Level Lower Level and Upper Level Discriminators These adjustments provide three control signals that help control the conversion process The zero level discriminator ZLD is active when the input signal is greater than half of the LLD setting The LLD is active when the input signal is greater than the LLD setting The ULD is active when the input signal is greater than the maximum possible ADC output ADC Control This circuit accept
32. nel Buffer Card SHOW_MDA Returns the uncorrected MDA in gammas s by calculating the right half of the MDA equation see SET MDA COEP and returns that value Example Responses MDA 000000000000 85 MDA 0 85 SHOW MDA COEFFICIENTS Returns the coeffficients used for the MDA calculation See SET MDA COEFFICIENTS Example Responses MDA COEF 000000000002 71 000000000000000 0000000000021 7 Coefficient a 2 71 b 2 0 and c 21 7 SHOW MDA PRESET Returns the current MDA preset setting Example Responses MDA 000000000000000 No preset MDA 0000000000008 5 Preset set to 8 5 SHOW MODE This command is for compatibility with Model 918 systems It always reports that the TRUMP PCI card operates in pulse height analysis mode Responses FPHA CR SHOW NEXT Used in conjunction with the SHOW ROI command SHOW NEXT reports the next continuous group of channels that have the ROI flag set The response is of the form Dsssssnnnnnccc CR where sssss represents an integer number that is the number of the first channel of the next group of channels that all have their ROI bit set and nnnnn represents an integer number that is the number of channels in the group If no more channels have their ROI bit set SHOW NEXT returns a first channel of 0 and a number of channels of 0 The SHOW ROI command is used to report the first group of channels that all have their ROI bit set Example Responses D0100000050078 lt CR gt
33. of counts Channel 16383 is the highest numbered channel in any device Responses C00000087 lt CR gt Maximum count was found in channel 0 or no ROI channels were found C00001088 lt CR gt Maximum count was found in channel 1 C08190105 lt CR gt Maximum count was found in channel 8190 C08191106 lt CR gt Maximum count was found in channel 8191 SHOW_PEAK_PRESET Reports the value of the ROI peak preset See SET PEAK PRESET for information about the ROI peak preset 29 TRUMP PCI 8K 2K Multichannel Buffer Card Responses G0000000000075 lt CR gt Peak preset disabled G0000000001076 lt CR gt Peak preset set to 1 count G2147483646120 lt CR gt Peak preset set to 2147483646 counts G2147483647121 lt CR gt Peak preset set to 2147483647 counts SHOW_RADIX This command is for compatibility with other ORTEC MCBs It always reports that the number base radix for the WRITE command is binary Responses FBIN lt CR gt Number base set to binary radix SHOW_RESET_DELAY Returns the current reset delay value added to the TRUMP PCT s 8 us minimum dead time Each unit of reset delay time a delaytick represents 80 ns See SET_RESET_DELAY Responses C00001088 lt CR gt Reset delay is 1 delaytick C00020088 lt CR gt Reset delay is 20 delayticks SHOW_ROI Used in conjunction with the SHOW_NEXT command SHOW ROI reports the first continuous group of channels that have the ROI flag set The response is of the form
34. ontains troubleshooting information 3 1 Live Time Mode The TRUMP PCI card has two different live time correction modes extended and simple The extended mode is the Gedcke Hale correction mode which corrects for losses caused by pile up in the shaping amplifier This is the default setting and is usually the correct setting for energy spectroscopy systems The simple live time correction mode simply stops the live time clock when the BUSY signal is active the TRUMP PCI card detects that a pulse is arriving at its input or the TRUMP PCI card is busy digitizing data The simple live time mode is appropriate only in very specialized situations and is not the correct setting for most users Figure 1 shows the location of the live time correction mode jumper J7 Remove the jumper for extended live time correction or leave it on for simple live time correction 3 v lithium backup battery 4 a Live time Mode Wi W2 Jumper off Extended A A Jumper on Simple eo D e Jumpers W1 and W2 J7 always in this position Figure 1 TRUMP PCI Jumper Settings and Backup Battery TRUMP PCI 8K 2K Multichannel Buffer Card 3 2 Installing the TRUMP PCI Card CAUTION Always turn the PC off and unplug it from the mains power supply before installing a card 1 Remove the PC cover 2 Remove the slot cover from an unused PCI slot 3 Insert the card at an angle to get the BNC connectors through the opening on the rear of the
35. orm Fmmmm vvv lt CR gt where mmmm is a 4 character model designator and vvv is a 3 character version designator Example Responses FTRMP 001 lt CR gt TRUMP PCI firmware version 1 reported SHOW WINDOW Reports the start channel and number of channels that are in the window of interest for the currently selected device in the form Dxxxxxyyyyyccc lt CR gt where Xxxxx is the start channel 0 through 8191 and yyyyy is the number of channels 1 8192 See SET_WINDOW for more information about the window of interest Example Responses D0000008192092 lt CR gt Window of interest reported as starting at channel 0 and continuing for 8192 channels START seg mask Starts the acquisition of spectral data The optional segment mask is provided for compatibility with other MCBs and may be any value from 0 to 65535 but is ignored by the TRUMP PCI card Execution Warnings 000005074 lt CR gt The acquisition is already started no changes made 000006075 lt CR gt A preset was exceeded acquisition was not started STEP_OFFSET_FINE Increases the fine offset by 1 hardware unit Returns the new setting in a C record STOP seg mask Stops the acquisition of spectral data The optional segment mask is provided for compatibility with other MCBs and may be any value from 0 to 65535 but is ignored by the TRUMP PCI card Execution Warnings 000005074 Acquisition already stopped no changes made 33 TRUMP PCI 8K 2K Multich
36. r 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 In addition the following symbols may appear on the product AN DANGER High Voltage N ATTENTION Refer to Manual Please read all safety instructions carefully and make sure you understand them fully before attempting to use this product Cleaning Instructions To clean the instrument exterior Disconnect the instrument from the power source Remove loose dust on the outside of the instrument with a lint free cloth Remove remaining dirt with a lint free cloth dampened in a general purpose detergent and water solution Do not use abrasive cleaners Allow the instrument to dry completely before reconnecting it to the power source iv 1 INTRODUCTION The ORTEC TRUMP PCI Multichannel Analyzer MCA brings our TRUMP multichannel buffer card into PCI format giving you a computer controlled multichannel pulse height analyzer for high performance data acquisition in nuclear spectroscopy applications The TRUMP PCI 8K 2K consists of a single slot PCI card and the MAESTRO 32 MCA Emulation Software for Microsoft Windows 95 Windows 98 and Windows Up to eight
37. s all of the various status signals and provides the control signals required to complete a conversion Microprocessor The microprocessor accepts the digital data and adds it to the spectrum When an input pulse arrives the sequence of events is as follows 1 ZLD goes active when the input reaches half of the LLD setting 2 When ZLD goes active the peak stretcher is switched to Hold mode 3 When peak detect goes active LLD PUR GATE and ULD are sampled If any of these signals rejects the pulse the peak stretcher is returned to Track mode If the pulse is accepted the linear gate is closed and the ADC is given the convert signal 4 When the ADC is finished converting the data is transferred to the microprocessor for histogramming the linear gate is opened and the peak stretcher is returned to Track mode 4 2 Dead Time in MCA and Amplifier When a detector preamplifier spectroscopy amplifier and MCA are combined to form a spectroscopy system the dead times of the amplifier and the MCA are in series The combination of the amplifier extending dead time followed by the MCA non extending dead time yields a throughput described by r The rate of events arriving at the detector is r and r is the rate of analyzed events in the MCA spectrum Tw is the width of the amplifier pulse at the noise discriminator threshold Fig 4 Tp is the time from the start of the amplifier pulse to the point at which the MCA detect
38. s available 0 6 MCS mode functions available 0 7 List mode functions available 0 8 Sample mode functions 0 9 Digital offset i e 920 1 10 Software selectable analog offset 0 11 HV power supply 0 12 Enhanced HV SH_HV_POL SH_HV_ACT etc 0 13 Software selectable HV range ENA NAI DIS NAT 23 TRUMP PCI 8K 2K Multichannel Buffer Card 24 TRUMP PCI 0 oO c O O O oo Bit 14 15 16 17 18 19 20 21 22 23 24 29 26 27 28 29 30 31 Beginning of 2nd word 1 oO m 32 33 34 35 36 37 38 39 40 Auto PZ Software selectable manual PZ Battery backed real time clock Sample changer support One button acqquisition via ENAB_TRIG_SPEC and MOVE commands Nomadic likely to move between opens Local app data SET DATA APP SHOW APP Software retrievable serial number SHOW SNUM Power management features CONSERVE ON OFF etc Battery status support SH STAT Software selectable AMP polarity Flattop optimization START OPTI cmd Stoppable Auto PZ STOP PZ AUTO cmd Network support i e DSPEC Multi drop serial support 1 MicroNOMAD Software selectable DPM address SET_DPM_ADDR Multiple devices i e 919 Software selectable ADC gate mode SET Software downloadable firmware Time histogramming functions available i e 9308 Software selectable LLD Software selectable ULD MCS mo
39. s not in warranty should 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 TABLE OF CONTENTS Safety Instructions and Symbols ee iv Gleanins ES UC HORS oc ow oU oed t EOS Ves HE EIN ERDE le iv 1 INTRODUCTION rn steht d to Ud dent hy heat iar ee ade see Ue a an 1 Pals Sime the Manual s dass cuneo en Dep cuu sb brad ua sta dcn 1 2 SPECIFICATIONS ra Viet oy RUP C PR arl OY RR RP QUA DE 3 221 GC PATE ED ue AR ti NEE 3 222 db he code ee Ne Cu rd 4 PAS PR APUS i A 4 2 4 Electrical and Mechanical 42 enel e ash sache a 4 2I2 Dolware PRetequ
40. s peak amplitude 10 4 MCA BASICS T Ty ADC Converting Tw gt Figure 4 The Sources of Dead Time with An Amplifier and MCA and closes the linear gate U T Ty T is a unit step function that changes from 0 to 1 when Ty is greater than Tw Ty is the conversion time of the ADC and includes the time required to transfer the data to the subsequent memory The TRUMP PCI card Extended Live Timer uses the Gedcke Hale method to correct for the dead time losses implied by Eq 1 When the counts in a full energy peak are divided by the live time the resulting counting rate is an accurate estimate of the true counting rate for that gamma ray energy at the detector output The Gedcke Hale method uses the amplifier analog output Busy and PUR pile up reject signals The amplifier dead time is combined with the ADC conversion and readout dead time to obtain the overall system dead time For accurate live time the PUR and BUSY signals must be connected from the amplifier to the TRUMP PCI card The Gedcke Hale live time clock works as follows Either the leading edge of the amplifier Busy signal or the crossing of the ADC LLD by the ADC Input causes the live time clock to start counting backwards The live time clock is turned off by the ADC peak detect or by the amplifier PUR signal The live time clock resumes counting forward after all of the following signal
41. t open 3 INSTALLATION OUTPUT PREAMP POWER gt gt INPUTS 8 SkV HIGH VOLTS LINEAR INHIBIT OUTPUTS PREAMP BIAS SHUTOOWN H REMOTE SHUTDOWN L TRUMP PCI REAR PANEL 659 660 OR 459 672 AMP BIAS SUPPLY REAR PANEL REAR PANEL Figure 2 HPGe System Cabling 3 5 Adjusting the Lower and Upper Level Discriminators The lower level discriminator LLD and upper level discriminator ULD are set in MAESTRO with the ADC Setup function under the Acquire menu The LLD adjustment is used to prevent small noise pulses from being converted by the ADC Converting the noise pulses causes the ADC to incur a large amount of dead time which prevents the ADC from converting the actual pulses of interest When the TRUMP PCI card is shipped from the factory the LLD is set at 40 channels and the ULD setting is 8000 channels These are adequate for most systems If the system has high noise or there is a very low energy peak in the spectrum it may be advantageous to adjust the LLD setting In the high noise system start collecting data and observe the dead time on the screen along wi
42. th the number of counts arriving at the low end of the spectrum In MAESTRO increase the LLD setting until the dead time drops or the peaks due to noise at the low end of the spectrum stop getting new counts TRUMP PCI 8K 2K Multichannel Buffer Card If there is a low energy peak in the spectrum it may be necessary to lower the LLD setting to prevent the peak from being rejected Start data acquisition and observe the low end of the spectrum while decreasing the LLD setting Continue the adjustment until the peak is in the spectrum fthe dead time goes to 100 increase the LLD setting 3 6 Setting the Zero Adjustment The zero adjustment adds or subtracts a dc level from the input signal Set the zero adjustment in MAESTRO with the ADC Setup function under the Acquire menu Usually no zero adjustment is required or recommended since most modern spectroscopy amplifiers have very little dc offset 3 7 Enabling the Gate Input The GATE connector operates in one of three modes Off the Gate Input does nothing Coincident for a pulse to be converted the Gate Input must be active 22 5 V when the pulse reaches its peak and for 0 5 Ls thereafter Anticoincident for a pulse to be converted the Gate Input must be inactive 0 8 V when the pulse reaches its peak and for 0 5 Us thereafter When the TRUMP PCI card is shipped from the factory the Gate Input is set Off To change the setting use Acquire ADC Setup
43. the ROI flags for the specified channels This command can be used multiple times to set ROI flags without affecting previously set flags ROI flags specify channels within a device that are considered for ROI integral and ROI peak presets SET ROI MDA start chans Sets the region to be used for the MDA preset calculation SET ROI UNCERTAINTY start chans Sets the region to be used for the uncertainty preset calculation See also SHOW ROI UNCERTAINTY SET TRUE ticks Sets the true time counter for the currently selected MCB to the specified number of 20 ms ticks The number represents true time in units of 20 ms 50 ticks per second Normally this value is set by the TRUMP PCI during data acquisition See also CLEAR COUNTERS and SHOW TRUE Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET TRUE PRESET ticks Sets the true time preset to the specified number of ticks 20 ms During data acquisition when the true time counter reaches the preset number of ticks the preset is complete and the acquisition is stopped Setting a true time preset to 0 ticks disables the preset See also CLEAR PRESETS and SHOW TRUE PRESET 21 TRUMP PCI 8K 2K Multichannel Buffer Card Execution Errors 131135083 lt CR gt The command was attempted while spectrum acquisition was in progress No action was taken SET_ULD i This sets the upper level discriminator to the value
44. the new device s channels are available Only device number 1 is valid for a TRUMP PCI This command has no effect in the operation of the TRUMP PCI Execution Errors 131128085 lt CR gt An invalid device number was given SET GAIN CONVERSION chans 18 Sets the conversion gain The conversion gain defines the number of channels within the device that will used for spectral data This has the effect of altering the resolution of the ADC from 13 11 bits conversion gain 8192 2048 to 9 bits conversion gain 512 for the device Legal Commands SET GAIN CONVERSION 0 CR Conv gain set to default 8192 or 2048 SET GAIN CONVERSION 512 CR Conv gain set to 512 channels SET GAIN CONVERSION 1024 CR Conv gain set to 1024 channels SET GAIN CONVERSION 2048 CR Conv gain set to 2048 channels SET GAIN CONVERSION 4096 CR Conv gain set to 4096 channels SET GAIN CONVERSION 8192 CR Conv gain set to 8192 channels 5 COMMANDS AND RESPONSES SET_GATE_ANTICOINCIDENT Causes the MCB to expect the ADC gate input signal in anticoincident mode See the section on the ADC gate input for more information See also SET_GATE_OFF SET GATE COINCIDENT and SHOW_GATE SET GATE COINCIDENT Causes the MCB to expect the ADC gate input signal in coincident mode See the section on the ADC gate input for more information See also SET GATE OFF SET GATE ANTICOINCIDENT and SHOW GATE SET GATE OFF Causes the MCB to ignore the
45. turns a record that indicates the hardware configuration of the MCB The record contains information about the number of segments in an MCB device always one for the TRUMP PCI and the current conversion gain for each segment The record is organized as follows 22 5 COMMANDS AND RESPONSES J0819200001aaaaa00000 65 zeros here for total of 75 zeros 00000ccc for 8K J0204800001aaaaa00000 65 zeros here for total of 75 zeros 00000 for 2K Where aaaaa represents the conversion gain for the one and only segment in the currently selected device and ccc represents the record checksum See the section on response records in this appendix for more information about response records and checksums SHOW CONFIGURATION MASK Returns two masks the first of which may be anded with data from the MCB to clear the ROI bit from the data When the second mask value is anded with data from the MCB the data bits are removed and only the ROI bit remains Response CONF MASK 02147483647 02147483648 SHOW FEATURES This command returns the hardware feature mask to show which features are available in the selected MCB Response FEATURES 0000000000 0000000000 0000000000 Feature mask bit definition bit number starts on right TRUMP PCI Bit Meaning 1 0 Software selectable conversion gain 0 1 Software selectable coarse gain 0 2 Software selectable fine gain 0 3 Gain stabilizer 0 4 Zero stabilizer 1 5 PHA mode function
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