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Digitizers User Manual

1. ccccescceseeeseesseeseeeseeeseesececesseeaecaecnaecaecaeecaeeeseeeseenseeneenes 58 3 19 1 Preparations before Pwer Off sessir ecer a eteesi o e ee a e paea a Ea EEE ia 58 3 19 2 Recovery atter Power Oido a a 58 3 20 Reading the Instrument Temperature oooconcninonionnonnconnconconncnnnonn nono nonn ono nonn nro nr nn nn corr nnn ron ran rana nn rra 59 4 APPENDIX A ESTIMATING DATA TRANSFER TIMES 0 cssssssssscsessesecsessesecnessesessesecsessesesnesseseenens 60 41 Principles de Formulas a het ee 60 IN A a E E ies setedgueeeveegid evtedseesleeee da EE E E EaI o EENE 61 4 3 Comparison Chart for Typical Transfers cccccecccesscesscesscesecesecenecsaecseecneeeaeeeeeseeeseeeseeeeesereneeneeeeecaeeeaes 62 Programmer s Guide Page 4 of 63 1 Introduction 1 1 Message to the User Congratulations on having purchased an Agilent Technologies Acqiris data conversion product Acqiris Instruments are high speed data acquisition modules designed for capturing high frequency electronic signals To get the most out of the products we recommend that you read the accompanying product User Manual this Programmer s Guide and the Programmers Reference manual carefully We trust that the product you have purchased as well as the accompanying software will meet with your expectations and provide you with a high quality solution to your data conversion applications 1 2 Using this Manual This guide assumes you are familiar with the
2. The digitizer sees the multiple clock bursts as a single acquisition It knows neither the sampling frequency nor the time difference between the waveforms It simply acquires a number of data points In termination mechanism 2 it also records the extraneous points and then stops When reading the data the multiple waveforms appear as a contiguous waveform The only way of distinguishing one waveform from the other is by counting samples i e the first 2000 samples belong to the 1 waveform the next 2000 to the 2 etc It is therefore imperative to exactly control the number of clocks in a burst NOTE If the time difference between 2 bursts is gt 100 ns the digitizer tends to drift into saturation from which it has to recover when the next burst resumes The first data sample of such a burst is thus invalid In many cases this first data sample is sufficiently different from the rest of the waveform that it can serve as a segment marker NOTE Digitizers that have more than one converter channel DC211 DC240 DC241 DP210 DP211 and DP214 will generate two four for theDC211 data samples for each sampling interval You must dimension your acquisition and readout for twice 4x the normal amout of data and can then either drop the extra data sample from the record or average the data values which could enhance the signal to noise ratio 3 17 ASBus Operation The ASBus and ASBus are intended to synchronize a number of si
3. amp stopDelay Comments The value of the second argument to AcqrsD1_configA vgConfig must always be 0 When in buffered mode the following digitizer parameters are ignored delayTime of the function AcqrsD1_configHorizontal is replaced by StartDelay and StopDelay nbrSamples and nbrSegments of the function AcqrsD1_configMemory are replaced by NbrSamples and NbrSegments in the function AcqrsD1_configAvgConfig The values nbrSamples startDelay and stopDelay must be integer multiples of the acquisition block size which is always 16 in the AP101 and 32 in the AP201 If the supplied value is not an integer multiple of the acquisition block size it is truncated to the next lower integer multiple Thus nbrSamples 250 will be truncated to 240 15 16 on an AP101 and to 224 7 32 on an AP201 You can query the actual value with the function AcqrsD1_getAvgConfig The value startDelay controls the time between the trigger and when the first digitized data sample is stored The stopDelay permits the addition of an extra delay to the dead time between the acquisition of subsequent waveforms Its minimum value may be zero Although not shown here a call to AcqrsD1_configControllO can be made in order to set a trigger veto time to be respected after the receipt of a Prepare for Trigger signal on a Control I O connector Also not shown is a call to the function AcqrsD1_configAvgConfig to set a timeout val
4. delayTime Time until Acquisition Stop Comments sampInterval 0 Trigger point is at the right edge of grid i e at the end of nbrSamples the nominal waveform 100 pre trigger lt 0 sampInterval nbrSamples Trigger point is at the desired point within the grid delayTime 0 sampInterval nbrSamples Trigger point is at the left edge of grid i e at the beginning of the nominal waveform 0 pre trigger gt 0 sampInterval nbrSamples Trigger point is to the left of the grid i e before the delayTime beginning of the nominal waveform post trigger Note that delayTime is not allowed to become more negative than sampInterval nbrSamples because it is impossible to stop the acquisition before the trigger occurs 3 13 Horizontal Parameters in Acquired Waveforms Triggers usually occur asynchronously with respect to the sampling clock Thus between similar events the time from the trigger to the next sampling clock varies randomly in the range 0 sampInterval The true time reference for any waveform is the trigger point not the sampling times because the trigger is attached to a given feature of the waveform e g a transition at a predetermined level For highly stable displays it is important to know the time between the trigger and the next sampling clock to within a fraction of the sampling interval and to place the displayed data points in such a way that the trigger point stays at a constant position This is
5. 5 You may now do any additional processing in your computer However you cannot read the original data at this point without perturbing the acquisition 6 Now that you have finished all work with the current data you can loop to 3 above A typical acquisition processing readout sequence in explicit buffered mode would be 7 Configure the APXO01 for appropriate channel timebase trigger and gate parameters 8 Start the first acquisition 9 Wait for the first acquisition to terminate 10 Switch the memory bank and start a new acquisition in the second bank Note that you must start the new acquisition to make the memory bank switch happen 11 Start data processing This can overlap with the data acquisition since it automatically deals with the memory bank that is not selected for acquisition 12 After processing has terminated read the processed result Note that the processing will not destroy the originally acquired data 13 You may now do any additional processing in your computer However you cannot read the original data at this point without perturbing the acquisition 14 Wait for the new acquisition to terminate 15 If you need to read the original data e g for diagnostics on the processing algorithm you may now do so 16 Loop to 4 above You need to implement a method to interrupt the infinite loop whenever required However you should make sure that you leave the acquisition in a well determined state f
6. AcgrsDl _multilnstrDefine idList nbrinList masterIndex multiInstrID status Acgrs calibrate multalnstriD The first part of the code above finds and initializes all individual digitizers as shown in section 3 2 1 PCI amp VXI Identification by Order Found Of course you could also use one of the other 2 methods of identifying individual digitizers After AcqrsD1_multilnstrDefine has executed successfully the instrumentID s in the list idList become unavailable for further operations You must use the returned multilnstrID to refer to the newly defined Multilnstrument You are responsible for making sure that e all participating digitizers are physically connected with ASBus bridges e the modules are of the same model type e the master module has no more memory than any other participating digitizer e an AcqGeo map file is available if needed by the driver If the master module has more memory than any other digitizer the combined instrument will work as long as you never request more memory than that available in the unit with the shortest memory The digitizers within the manually defined Multilnstrument are numbered from 0 to nbrinList 1 exactly as presented in the digitizer list idList For details on channel and trigger source numbering please refer to section 3 17 ASBus Operation 3 2 9 AqGeo map file positioning For ASBus Multilnstruments in some systems the driver will need additional information abou
7. AqDx Example Scope Vii tia 10 2 3 4 AqDx Accumulated Waveform Example VI ooonooniconiccioccnocconncononnncnnnonn nono nonnnonnrnnnonnnnnn rn n rn nn carr narran 11 DN CATA TES O Vi ici 12 23 6 AQT TC890 UA idas 13 2 45 Visual Basica mini A A ee ean ee ion ade cela 13 Dido SMAMIEAB s cic deitss ccc tatas e e sas E AEE AAE santa so coletas Labs ol 14 2 6 Wind River VxWorks Tornado ccccesseessesseeseeescescceccesecesecsecaeceaecsaecaeecaeeeaeeeeeseesaeeneeenseenseenaeenseensecaes 14 2 6 1 Complot ce lines doo leia llos o ala AN do chess de on oo ll 15 2 6 2 LOA MN A A A eB TEAN O AT SUA INS 15 2 6 3 Running the Brosrani s a a Cassone teo E ele ieee Ca ene ens 15 PAT N O TO RON 15 PROGRAMMING AN ACQIRIS INSTRUMENT cscccsssssssssessesessessesecnessesecnessesecnesesesnessesecesseseenesseses 16 Bal Programme Hits cita EE N EEE E 16 3 27 Device Initialization ici c 59s cn e t e E e E E eden eaten doing i 16 3 2 1 PCI amp VXI Identification by Order Found cececceseessecsseeseeeseeeseeeeeesecesecesecaecsaecaeecaaeeneeseecaeeeneenes 17 3 2 2 PCT Identification by Serial Number comi id das 17 3 2 3 PCI Identification by Bus Slot Number sssrinin 17 3 2 4 VXI Identificate a Hie eae pee ot ston he ona none neti 18 3 2 5 PXI VISA amp LabViewRT Identification eee eseseeecsseceeecseesececeeecesecaeesecaeeeeesecaeesesneeeeceaeeneeneeas 18 3 2 6 Firmware initialization AP FAMILY 12 bit FAMILY AC
8. INSTRO Select an INPUT channel and set ts level Set the level for COM IN Name Set the number CountEvent for the number of starts for each acquisition You can also set the number of intervals to be used to compute the a histogram Serial Number pm WARNING The horizontal axis is recomputed for each acquisition Number of Channels o TDC Resolution 1 00 Calibrate Mi INPUT 11 INPUT level v 01 COM IN level v 10 commstope Negative INPUT Slope Negative x Histogram CountEvent 10000 intervals 10 a z mean value 0 7 i l 7 LERS 1 9 00000 111 22n 111 25n 111 30n 111 35n 111 40n 111 45n 111 48n Hide error out This VI demonstrates how to use a TC890 Time Counter It finds and initializes an instrument sets the basic parameters according to the controls on the front panel and then acquires and accumulates data on the common and the chosen channel as the user requests Note that the front panel controls should be set to their desired values before the VI is run 2 4 Visual Basic Visual Basic support is available for Versions 5 0 or 6 0 with sample programs in the VB directory Basic NET support AcqrsD IInterface vb is also available but there are no sample programs yet The Visual Basic sample program comes in 8 bit and 12 bit versions The 12 bit programs can also be used for the 10 bit digitizers They each consist of 3 major parts 1 The AcqrsD1Interface bas fil
9. segment corresponds to the segment that was being recorded when the stop command was received The 4 segment in this example typically does not contain any useful data 3 19 Readout of Battery Backed up Memories Acqiris digitizers with the battery back up option permit retaining acquired waveforms during periods of time when the power might be interrupted 3 19 1 Preparations before Power Off A digitizer only remembers the digitized data array but not all of the parameters that are needed to interpret the waveform These parameters are normally retained in the driver but are typically lost when power is lost or when the controlling application is terminated It is therefore necessary for the application to transfer the relevant parameters before power off typically to a disk in such a way that they are again available when restarting the application after power is restored The following parameters must be transferred to persistent storage for each instrument e Parameters of AcqrsD1_configHorizontal i e sampling interval and delay e Parameters of AcqrsD1_configMemory i e number of samples and number of segments e Parameters of AcqrsD1_configVertical i e Full Scale and offset the coupling is not relevant for each channel of interest e Two calibrated delay parameters as obtained with the function calls Double delayOffset delayScale Acgrs getInstrumentInfo ID DelayOffset amp delayOffset Acqrs getInstrumentInfo
10. tmax and gt tmax respectively Sample tmax validLeft and Sample tmax validRight are the first and last valid points respectively If you need to know the segment time stamps you can read the gated data If the user or threshold gate parameters are set appropriately the amount of unwanted data can be minimized 3 10 7 3 Reading the peaks The results for all of the peaks in the current event can be read out using readMode 4 ReadModePeak The waveform descriptor structure contains the value actualDataSize giving the total number of data bytes read There may be a variable number of blocks of data with the following format Peak block 31 24 8 bits 23 19 4 16 bits 3 0 4 bits Programmer s Guide Page 41 of 63 Flag 00010000 Unused Peak amplitude with ADC resolution Interpolated fractional part of 0x10 amplitude 1 16 LSB 29 4 26 bits 3 0 4 bits Peak Position with sample rate resolution Interpolated fractional part of position 1 16 sample interval The peak position is counted relative to the beginning of the first segment of the acquisition Thus the position also gives the segment number of the peak The peak amplitude is the value acquired after baseline substraction When reading such data you should carefully check that you terminate correctly and do not read beyond the end of the transmitted data nor generate unphysical time coor
11. wait the appropriate settling time before it starts the acquisition This is done to ensure that the acquisition will occur in the desired state The program does not have to include ad hoc waits to allow the analog hardware to settle The settling times vary from none in the case of no change to 0 5 ms in the case of offset changes and to 5 ms for relay changes or changes between normal operation and External Clock Reference In the special case of switching from DC to AC coupling the settling time is 100 ms Time base setting changes also have associated settling times NOTE The special case of making transitions from low to high impedance is treated immediately to avoid the risk of damaging the front end circuitry of the digitizer When making transitions from high to low impedance you must ensure that large voltages are not applied before the change has really happened Therefore it is recommended to wait 5 ms after having asked for an impedance change and before applying any large voltages Impedance changes can also affect other devices in the signal path Unneeded calls to the AcqrsXX_config functions should be avoided because they can delay the start of the next acquisition NOTE The AcqrsXX_get functions return the configuration values to be used for the next acquisition Use the following short code fragment for a device configuration Programmer s Guide Page 21 of 63 Configure double sampInterval 1 e 9 delayTime 0
12. 0 long nbrSamples 10000 nbrSegments 1 long channel 1 coupling 1 bandwidth 0 double fullScale 2 0 offset 0 0 long trigCoupling 0 trigSlope 0 double triglevel 20 0 in of vertical Full Scale AcgrsD1_configHorizontal instrID sampInterval delayTime AcgrsD1_configMemory instrID nbrSamples nbrSegments AcgrsDl_configVertical instrID channel fullScale offset coupling bandwidth AcgrsDl_configTrigClass instrID 0 0x00000001 0 0 0 0 0 0 AcgrsDl_configlrigSource instrIiD channel trigloupling trigSlope trigLevel 0 0 Comments Channel numbers run from 1 to nbrChannels not from 0 Segment numbers however run from 0 to nbrSegments 1 If the desired sampling interval implies that multiple converters channel will be needed a call to AcqrsD1_configChannelCombination will be needed before the call to AcqrsD1_configHorizontal Specifying more than 1 segment in AcqrsD1_configMemory implies the use of Sequence mode The 10 bit FAMILY amp DP1400 instruments offer additional functionality through AcqrsD1_configMemoryEx This includes the Simultaneous Multibuffer Acquisition and Readout SMAR mode to allow a higher loss less trigger rate For 10 bit units with extended memory there is the possibility of restricting memory use to the internal memory to reduce the maximum dead time between segments of a sequence acquisition The 5 main configuration funct
13. DC271A 20 2000 14 x inputFrequency 1 x inputFrequency 2 x inputFrequency DC271AR DC282 100 2000 1 x inputFrequency 2 x inputFrequency 4 x inputFrequency DC436 100 200 4 x inputFrequency DC440 DC438 100 220 1 x inputFrequency DP 1400 10 2000 1 x inputFrequency 2 x inputFrequency DP214 20 2000 1 x inputFrequency DP235 AP235 20 1000 1 x inputFrequency 1 x inputFrequency DP240 AP240 20 2000 14 x inputFrequency 1 x inputFrequency DP306 100 200 4 x inputFrequency DP308 100 200 1 x inputFrequency DP310 100 220 1 x inputFrequency Programmer s Guide Page 51 of 63 Model Input sFmax vs nbrConvertersPerChannel Frequency range MHz 1 2 4 AC210 SC210 20 2000 4 x inputFrequency AC240 SC240 20 2000 14 x inputFrequency 1 x inputFrequency 1 generation 100 500 1 x inputFrequency Example When using a DC241 with 2 combined channels and an external clock frequency of 1800 MHz inputFrequency the possible sampling frequencies are 3 6 GS s 1 8 GS s 900 MS s and 450 MS s The ratio of sFmax to inputFrequency can also be learned at run time by using a call to Acqrs_getInstrumentInfo instrID ExtCkRatio amp ratio The system computes the required memory overhead in data samples on the basis of the current sampFrequency and nbrConvertersPerChannel Use the function AcqrsD1_bestNominalSamples to obtain the maximum available memory after setting these parameters The equivalent of de
14. ID DelayScale delayScale The functions Acqrs_getInstrumentInfo should be called just before the start of the acquisition i e before calling AcqrsD1_acquire but after all AcqrsD1_config functions 3 19 2 Recovery after Power Off In order to read a battery backed up waveform you need to execute a special sequence of initialization functions 1 Initialize the digitizer with the following function call Acqrs InitWithOptions resourceName false false CAL FALSE amp instrID It is important to specify CAL FALSE to prevent any calibration in the digitizer which would destroy any retained data 2 Call the functions AcqrsD1_configHorizontal AcqrsD1_configMemory AcqrsD1_configVertical for each channel with the same parameters that were used in the original acquisition Programmer s Guide Page 58 of 63 3 Call the function AcqrsD1_restoreInternalRegisters with the parameters delayOffset and delayScale In case these parameters are not available e g due to earlier software versions you should use the values 20 0e 9 for delayOffset and 5 0e 12 for delayScale 4 Call the function AcqrsD1_readData to read the battery backed up data Failing to restore the originally used digitizer parameters may result in erroneous data After data recovery and before using the digitizer for any new acquisitions don t forget to calibrate the instrument with the function Acqrs_calibrate 3 20 Reading the Instrum
15. ReadModePeakPic The waveform descriptor structure contains the value actualDataSize giving the total number of data bytes read There will be a variable number of blocks of data with the following format Peak region block 8 points 31 24 8 bits 23 16 8 bits 15 8 8 bits 7 0 8 bits Flag 00010010 0x00 Valid Left Valid Right 31 0 32 bits Peak Position tmax 31 24 8 bits 23 16 8 bits 15 8 8 bits 7 0 8 bits Sample tmax Sample tmax 1 Sample tmax 2 Sample tmax 3 Sample tmax 4 Sample tmax 3 Sample tmax 2 Sample tmax 1 Peak region block 16 points 31 24 8 bits 23 16 8 bits 15 8 8 bits 7 0 8 bits Flag 00010001 0x00 Valid Left Valid Right 31 0 32 bits Peak Position tmax 31 24 8 bits 23 16 8 bits 15 8 8 bits 7 0 8 bits Sample tmax 4 Sample tmax 5 Sample tmax 6 Sample tmax 7 Sample tmax Sample tmax 1 Sample tmax 2 Sample tmax 3 Sample tmax 4 Sample tmax 3 Sample tmax 2 hb Sample tmax Sample tmax 8 Sample tmax 7 Sample tmax 6 Sample tmax 5 The peak position is counted relative to the beginning of the first segment of the acquisition Thus the position also gives the segment number of the peak The sample data value is the raw data value Valid Left and Valid Right give the number of valid data points lt
16. SC Time Counters 0 0 0 cceseeseeeeneees 18 3 2 7 Automatic Definition of Multilnstrument cc ceecccescessceeeceseceeceseceecseeeseecaecaeecaeeeseeeeeeeeeeeeeeereerees 18 3 2 8 Manual Definition of MultiInstrument 0 ccecceccesseesseesceeeceeecesecesececnseeseesaeceaecaaecaeeeaeeeneeeeeeeneees 19 32 9 AqGeo map file positioniti E ii Ai 20 3 2 10 Simulated DEVICES conil ne A a ne e deed eo wT aes 21 32 11 Termninating an Applicatiof iaon a id iebc a 21 3 32 Device Configuration A sek ca eco cn ee ee Rie edge ces RRL on else OR 21 3 4 Config ring AVerageTSs ida 23 3 4 1 Basie Configuration A A a dida ts 23 3 4 2 Di oa 24 3 4 3 Fixed Pattern Background Subtraction sseseeessseeeesseserseesersessteresststseesersessteresstsesresstsesseenessreressese 24 3 4 4 Configuring Noise Suppressed Accumulation NSA ccscccssessseeseeeseeeseeseeeseeesecaecseecaeeeneeeseeeeeeneeees 25 3 5 Configuring SSR Analyzers ia E 26 35 1 Acquisition Parameters iii innan n i e i ti ieii 26 3 5 2 Readout configurations iii E E E A iii 27 3 5 3 Time stamps da ibas 28 3 6 Configuring PCa ge Analyzers ens te i et i ete ttet sste tel a Wich hana ede ae 28 3 7 Configuring AP101 AP201 Analyzers 0 eccececeesseesseeseeeseeeseeeceescenseenseensecnaecaaecseecaeseseeeaeseeeeeeesseeneeeeeaees 29 3 8 Configuring TC8xx Time Counters iese renent enie p nae ei i a irie inie iie 29 392 R DT Wea TETI To al tas r
17. XP environment the operation of AP_SSRDemo and in the following chapter APx01Demo applications that enable basic operation of Acqiris analyzers in a Windows 2000 XP environment the operation of DemoTC the demonstration program that enables basic operation of Acqiris Time Counters in a Windows 2000 XP environment the operation of AcqirisAnalyzers the demonstration program for the SC240 AC240 SC210 AC210 from a PC running a Windows 2000 XP operating system This Programmer s Guide is divided into 3 separate sections Chapter 1 INTRODUCTION describes what can be found where in the documentation and how to use it Chapter 2 PROGRAMMING ENVIRONMENTS amp GETTING STARTED provides a description for programming applications using a variety of software products and development environments Chapter 3 PROGRAMMING AN ACQIRIS INSTRUMENT provides information on using the device driver functions to operate an Acqiris instrument The accompanying Programmer s Reference manual is divided into 2 sections Chapter 1 INTRODUCTION describes what can be found where in the documentation and how to use it Chapter 2 DEVICE DRIVER FUNCTION REFERENCE contains a full device driver function reference This documents the traditional Application Program Interface API as it can be used in the following environments LabWindowsCVI Visual C LabVIEW MATLAB Visual Basic Visual Basic NET Programmer s Guide Page 5 of 63 1 3 Conventions Use
18. acquired averaged waveform should result in more precise data In order to facilitate the acquisition of the fixed pattern background the Averager modules offer the following possibilities e disconnection of the input with the value coupling 0 in the function AcqrsD1_configVertical e acquisition of an averaged waveform without a trigger signal with the value TrigResync 2 free run in the function AcqrsD1_configAvgConfig However you get a better measurement of the fixed pattern background if you acquire with the same trigger conditions as the averaged waveforms that will be corrected Typically it is better to continue using an external trigger signal rather than TrigResync 2 The fixed pattern background should be acquired in the same conditions as the averaged waveforms that will be corrected In particular the dithering range and the number of waveforms should be the same Use the following code fragment to acquire a fixed pattern background with a free running trigger const long channelNbr 0 double fsr offset long coupl bwidth reSync freeRun 2 Make an acquisition at the current conditions but with Grnd coupling and free running trigger AcgrsD1_getVertical instrID 1 amp fsr Soffset amp coupl amp bwidth AegraDl contigvertical instrib 1 fsr offset D bwidth AcqrsD1_getAvgConfig instrID channelNbr TrigResync amp reSync AcqrsD1_confi
19. acquiring some additional data depending on the delayTime and the data acquisition time that were initially configured Thus the application should again wait for the acquisition to terminate Forcing a trigger does not make sense for averagers and analyzers and should not be done AcqrsD1_forceTrigEx allows you to generate a trigger out signal which can be synchronized with the sampling clock if desired Use the following code fragment to replace STOP ACQUISITION in the previous section AcgrsD1_forceTrig instrID if AcqrsD1 waitForEndOfAcquisition instrID timeOut ACOIRI 5 ERROR ACO T IMEOUT AcgrsDl_stopAcquisition instriD SCREAM because a major error occurred Note that no timeout should ever occur when waiting for a forceTrig to terminate provided that the timeOut value was made large enough If a timeout does occur this would indicate a failure in the digitizer or the entire system For users generating triggers under software control it may be desirable to do the data readout in a way that just gives the acquired data points and ignores the correction of the data gotten from the horPos measurement of the time from the trigger to the next data sample This can be done using the flags parameter of the AqReadParameters structure 3 9 5 Analyzer and Peak Autoswitch mode If with the Peak P mode the TdcHistogramMode parameter has been used to enable histogramming the desired number of acquisitions
20. after the event has occurred then the Sequence Wrap mode is applicable While this mode even works for nbrSegments 1 in practice the value of nbrSegments should be at least 2 It is important to note that after the acquisition of a segment the digitizer automatically advances to the next memory section and immediately with a dead time of 1 us starts recording into it Thus the very last memory segment will necessarily contain uninteresting data since it will not be stopped with a trigger but be terminated with the software command AcqrsD1_stopAcquisition Use this code to use the Sequence Wrap mode Programmer s Guide Page 57 of 63 AcgrsD1_configXXX configure other parameters AcgrsDl_configMode instrID 0 0 2 Acgrsbl_acquire iistriD AcqrsDl_stopAacquisition instribD The time at which the sequence is terminated with the function AcqrsD1_stopAcquisition depends on an external event e g operator intervention When reading the segments the segment number should take on the values 0 nbrSegments 1 They correspond to the memory section numbers in the digitizer not the time order of the acquired segments Example if nbrSegments 8 the time order of the acquired segments might be depending on when the sequence was stopped 5 6 7 0 1 2 3 4 Here the oldest good segment is the qe segment followed by the A A etc The youngest useful segment is the 3 one while the 4
21. be activated using the defined base value The order of the calls to AcqrsD1_configAvgConfig is not important since the final decision is taken when the acquisition is started Here is an example Programmer s Guide Page 25 of 63 const long channelNbr 0 double fsr offset threshold base threshold offset place the threshold at the middle of the screen base threshold fsr 10 place the base one division below the threshold set the base and threshold voltage values AcqrsD1_configAvgConfig instrID channelNbr Threshold amp threshold AcqrsD1_configAvgConfig instrID channelNbr NoiseBase amp base enable the NSA functionality AcqrsD1_configAvgConfig instrID channelNbr ThresholdEnable 1 AcqrsD1_ configAvgConfig instriD channelNbr NoiseBaseEnable 1 3 5 Configuring SSR Analyzers 3 5 1 Acquisition Parameters The AP235 AP240 SSR analyzers have 2 operational modes normal and AutoSwitch controlled with the function AcgqrsDl_configMode instrID mode 0 0 The value mode can be set to 0 normal or 7 AutoSwitch The AutoSwitch mode requires a number of additional configuration parameters that describe the requested acquisition and readout conditions Use the following short code fragment to configure a buffered acquisition sequence of 800 waveforms of 5000 data points with a start delay of 128 samples Common Configure long nbrSamples 5000 nbrSeg
22. be used in this mode A continuous clock frequency of up to 800 MHz to give 800 MS s sampling will work In this mode the horizontal control parameters sampInterval and delayTime are completely ignored as well as the value of delayNbrSamples The waveform length is as usual controlled by the number of samples in the function AcqrsD1_configMemory Careful synchronization between the function calls to the driver and the generation of the clock burst is required There are 2 ways of terminating an acquisition in the start stop mode 1 Generate a number of clock transitions that corresponds exactly to the requested number of samples and stop the acquisition with the function AcqrsD1_stopAcquisition This requires that the host computer obtain some external signal when the clock sequence is terminated 2 Generate some extra clock transitions which will fully terminate the acquisition You can then use the functions AcqrsD1_acqDone or AcqrsD1_waitForEndOfAcquisition to detect the end of acquisition Example for Termination 1 if you wanted to acquire 20 waveforms of 2000 data points each at a sampling rate of 33 3 MHz and a time distance of 5 us between the waveforms you would use AcgqrsD1_configMemory instrID 40000 1 AcgrsDl configExtClock instriD 4 threshold U 33 366 33 366 7 AcgrsD1_acquire instrID start the acquisition gt Generate 20 bursts of 2000 clock pulses at 33 3 MHz At the end you need to inform the
23. cannot ask for a reduced number of segments 3 10 6 2 Raw data The complete data should only be read out using the gated data mode described below An appropriate User Gate can be defined to access all of the data 3 10 6 3 Gated data Data can be read for both user and threshold gate operation using readMode 7 ReadModeSSRW The waveform descriptor structure contains the value actualDataSize giving the total number of data bytes read A time stamp block measuring the trigger time will mark the beginning of each segment Segment timestamps are mixed in with the data and not available through the usual segDesc array The entire time stamp is a 56 bit integer counting in units of 100 ns Here is the Time Stamp format Marker block 31 24 8 bits 23 0 24 bits Flag 00000100 0x04 Time Stamp MSB TimeStamp LSB The time stamp may be followed by a variable number of blocks of data with the following format Gate block 31 24 8 bits 23 0 24 bits Flag 00000000 Gate position from the origin of the acquisition not the segment 31 0 Gate length number of Data bytes always a multiple of 4 31 24 23 16 15 8 7 0 Data3 Data2 Datal Data0 Data4 When reading such data you should carefully check that you terminate correctly and do not read beyond the end of the transmitted data nor generate unphysical time coordinates for the data 3 10 6 4 Waveform sto
24. d i status Acgrs InitWithOptions resourceName VI FALSE VI FALSE options amp instrumentID i The calls to Acqrs_InitWithOptions are needed to obtain the instrumentID s The physical digitizers were already initialized when AcqrsD1_multilnstrumentAutoDefine was called The digitizers within a single Multilnstrument are numbered from 0 to NbrModulesInInstrument 1 In Acqiris CC10x compactPCI crates the module 0 is always closest to the controller slot i e module numbers increase with increasing front panel slot numbers This statement is also applicable to CC121 crate configurations with both an Acqiris acquisition module in one of the last 7 slots and with the PC running under Windows 2000 or XP Users of other systems or crates may need to provide AqGeo map files to give the driver needed information The GeoMapper application described in the User Manuals can create this file For details on channel and trigger source numbering please refer to section 3 17 ASBus Operation The master module is automatically chosen according to these rules ASBus e If modules of different memory lengths are combined only modules with the shortest memory length can be master modules e The master module is chosen as near as possible to the center module in order to minimize propagation delays ASBus 6U digitizers e The master module is chosen as near as possible to the center module in order to minimize propa
25. each recorded at 500 MS s T Ovhd py M Ovhd buffer M 1000 N 500 Xfr 0 012 Cpy 0 01 Ovhd py 100 Ovhdy yg 5 Extra 240 2 96 216 T M Ovhd py M N Xfr 100000 6000 106 000 us M N Extra Xfr M N Cpy 100 1000 5 1000 716 0 012 1000 500 0 01 18692 us The function AcqrsD1_readData for readMode 1 ReadModeSeqW is about 5 times faster 4 3 Comparison Chart for Typical Transfers 250 MHz Pentium 500 MHz Pentium 800 MHz Pentium T T2 R T T R T T R 0 20 0 22 1 10 0 21 0 25 1 17 0 30 0 52 1 72 120 3 22 2 68 10 2 30 2 2 96 0 10 0 12 1 13 0 11 0 13 1 20 0 20 0 31 1 56 110 2 11 1 92 10 1 20 1 1 99 0 06 0 08 41 17 0 07 0 09 1 22 0 16 0 23 1 45 1 06 1 70 1 60 10 0 163 1 62 2 02 043 0 21 2 10 0 67 0 32 3 00 3 37 1 12 12 0 304 2 53 102 300 2 94 102 0 26 0 25 110 042 0 38 2 00 2 22 1 11 110 20 2 1 84 101 200 1 98 0 65 0 19 0 30 0 73 0 32 0 45 163 1 79 1 10 10 6 164 1 54 101 163 1 62 202 247 0 12 21 0 4 87 0 23 30 0 31 9 1 06 120 302 2 52 10 2 1 67 0 16 11 0 3 27 0 30 20 0 21 3 1 06 110 202 1 83 6 45 1 37 0 21 725 2 67 0 37 16 2 173 1 06 106 164 1 54 202 229 0 11 210 46 9 0 22 300 317 1 06 102 15 8 0 16 110 31 8 0 29 200 212 1 06 64 5 13 2 0 20 72 5 26 2 0 36 163 170 1 06 Time in ms of Samples Segments Segment 1 200 1 1K 1 10K 1 100K 1 1M 10 200 10 1K 10 10K 10 100K 10 1M 1
26. for digitizer readout as a function of the number of segments number of samples CPU speed and the operating system 4 1 Principles amp Formulas The function AcqrsD1_readData for readMode 0 executes a direct waveform transfer from the digitizer memory to the user allocated buffer for a single segment at a time Since direct to memory access DMA is used this is the most time efficient method for segments of 10 000 or more samples However each segment requires its own DMA setup When segments are very short the transfer overhead starts to dominate the overall transfer time After the transfer the data in the buffer is ready to be used The function AcqrsD1_readData for readMode 1 ReadModeSeqW reduces the overhead time by transferring with a single DMA a complete digitizer memory image to the host computer memory The memory image is composed of a number of segments each of which is a circular buffer The first data point of interest in the circular buffer may be anywhere and its position usually changes randomly between acquisitions Thus after the DMA is terminated the driver must copy data from the image to the final linear buffer for each segment This method is therefore only interesting for relatively short segments However if timing is not an important consideration it offers the convenience of a single function call for the complete transfer of a waveform sequence Formulas for estimating the transfer times in us are e
27. is replaced by StartDelay and StopDelay in future software versions the parameter sampInterval of the function AcqrsD1_configHorizontal is likely to be replaced by SampInterval nbrSamples and nbrSegments of the function AcqrsD1_configMemory are replaced by NbrSamples and NbrSegments The values nbrSamples startDelay and stopDelay must be integer multiples of the averaging block size which is always 16 in the AP100 or AP240 AP235 Dual channel mode and 32 in the AP200 or AP240 AP235 Single channel mode If the supplied value is not an integer multiple of the averaging block size 1t is truncated to the next lower integer multiple Thus nbrSamples 250 will be truncated to 240 15 16 on an AP100 and to 224 7 32 on an AP200 You can query the actual value with the function AcqrsD1_getA vgConfig The value startDelay controls the time between the trigger and the first data sample that is to be added to the averager sum It is expressed in samples and must be an integer multiple of the averaging block size which is always 16 in the AP100 or AP240 AP235 Dual channel mode and 32 in the AP200 or AP240 AP235 Single channel mode The stopDelay permits the addition of an extra delay to the dead time between the averaging of subsequent waveforms Its minimum value may be zero It also is expressed in samples and must be an integer multiple of the averaging block size Programmer s G
28. not check the return value of the Acqrs_ functions In real applications you should always check the return values of functions 3 2 Device Initialization Before any real or simulated device can be used each device must be initialized with a separate call to the function Acqrs_InitWithOptions For real devices you can also use the slightly simpler function Acqrs_init Both functions return the instrumentID whose value will be different for each device which must be subsequently used in any other function call The arguments IDQuery and resetDevice are currently ignored The use of the string arguments resourceName and optionsString are explained with the initialization scenarios in the following sections If you use modules that are connected via ASBus you need to configure them as Multilnstruments This lets you treat them as normal instruments with an increased number of channels E g you can connect 3 DC270 s to form a single 12 channel 1 GS s digitizer If needed and before initializing the devices a call to either Acqrs_getNbrInstruments can be used to learn how many instruments have been found However a side effect of this call will be to select the use of single instruments This can be manually circumvented as discussed below or AcqrsD1_multilnstrumentAutoDefine can be used to automatically combine as Multilnstruments modules that are connected via ASBus and return the total number of instruments found including
29. operation of a personal computer PC running a Windows 2000 XP or other supported operating system In addition you ought to be familiar with the fundamentals of the programming environment that you will be using to control your Acqiris product It also assumes you have a basic understanding of the principles of data acquisition using either a waveform digitizer a digital oscilloscope or other similar instrument The User Manual that you also have received or have access to has important and detailed instructions concerning your Acqiris product You should consult it first You will find the following chapters there Chapter 1 OUT OF THE BOX describes what to do when you first receive your new Acqiris product Special attention should be paid to sections on safety packaging and product handling Before installing your product please ensure that your system configuration matches or exceeds the requirements specified Chapter 2 INSTALLATION covers all elements of installation and performance verification Before attempting to use your Acqiris product for actual measurements we strongly recommend that you read all sections of this chapter Chapter 3 PRODUCT DESCRIPTION provides a full description of all the functional elements of your product Chapter 4 RUNNING THE ACQIRIS DEMONSTRATION APPLICATION describes either the operation of AcqirisLive an application that enables basic operation of Acqiris digitizers or averagers in a Windows 2000
30. to step 0 in the table abov fegreDl contigkAvgContig i 3 AcgrsD1l acquire instriD 3 10 D1 style Data Readout For the reading of standard waveforms the AcqrsD1_readData routine should be used The following older routines will remain available but will no longer be discussed AcqrsD1_readCharWform AcqrsD1_readCharSequence AcqrsD1_readRealWform AcqrsD1_readRealSequence AcqrsD1_accumulateWform You should use the function AcqrsD1_readData for all new programs The older functions will not give support for new instruments or new functionality All variables of the AqReadParameters structure should be initialized 0 can be used for the reserved words For the readout of the averager data the read function AcqrsD1_readData described in 3 10 1 Reading Digitizer Waveforms with the Universal Read Function should be used with readMode 2 ReadModeAvgW For reading data from analyzers please refer to 3 10 6 Reading SSR Analyzer Waveforms or 3 10 7 Reading AP101 AP201 Analyzer Waveforms Programmer s Guide Page 34 of 63 3 10 1 Reading Digitizer Waveforms with the Universal Read Function For the general case which includes the reading of more complex waveforms we provide a universal read function AcqrsD1_readData Control of the read parameters is passed through the input structure AqReadParameters For the description of the output data an array of segment descriptors AqSegmentDescriptor and a waveform descriptor AqDataDescrip
31. will be taken automatically As usual the acquisition must be initialized with a call to AcqrsD1_acquire instrID When the acquisition has terminated the histogram data and the peak or gate data of the last acquisition will be available for readout The routines AcqrsD1_acqDone or AcqrsD1_waitForEndOfAcquisition must be used For all other cases the AP Analyzers implement an autoswitch mode that allows the dead time between acquisitions to be reduced to the minimum consistent with the readout of the data As usual the first acquisition must be initialized with a call to AcqrsD1_acquire instrID To allow the second acquisition to start as soon as possible a call to AcqrsD1_processData instrD processType 1 follows immediately Thereafter data can be read as soon as the processing is terminated and then the go ahead for the next acquisition can be given as desired Programmer s Guide Page 32 of 63 3 9 5 1 Sequence of actions for Autoswitch with event readout The AutoSwitch semaphore is set by the software and cleared by the FPGA If the readout process is longer than the acquisition process the AutoSwitch occurs directly after the software raises the AutoSwitch semaphore At the moment that the ProcessingEnd interrupt occurs the FPGA has already cleared the AutoSwitch disabled int disabled int acq Bank 0 O A A __Tdisatbied int acq Bank 1 A O J int
32. 00 200 100 1K 100 10K 100 100 K 1000 200 1000 1K 1000 10K 8000 200 1616 182 0 11 816 126 0 15 516 105 0 20 Programmer s Guide Page 62 of 63 Time in ms 250 MHz Pentium 500 MHz Pentium 800 MHz Pentium 8000 1K 1680 374 0 22 880 254 0 29 580 209 0 36 8000 2K 1760 614 0 35 960 414 0 43 660 339 0 51 Comments e We assume a 2 GS s digitizer running at the highest sampling rate direct connection of the digitizer to the host PCI bus or through the SBS Bit3 interface Acqiris model number IC200 Windows NT gt R T T If R gt 1 0 a loop over AcqrsD1_readData for readMode 0 is faster than AcqrsD1_readData for readMode 1 ReadModeSeqw Time in ms 866 MHz Pentium of Samples T T R Segments Segment 1 200 0 03 0 04 1 22 1 1K 0 04 0 05 1 21 1 10K 0 12 0 17 1 45 1 100 K 0 98 2 12 2 15 1 1M 9 85 25 5 2 59 10 200 0 3 0 14 0 46 10 1K 0 35 0 27 0 76 10 10K 1 21 1 61 1 33 10 100 K 11 6 16 2 1 40 10 500 k 454 944 2 08 100 200 3 00 0 92 0 31 100 1K 427 2 37 0 56 100 10K 16 1 15 0 0 93 100 50K 44 7 742 1 66 1000 200 47 2 13 5 0 29 1000 1K 44 3 234 0 53 1000 5K 85 9 87 8 1 02 8000 200 457 64 8 0 14 8000 500 496 202 0 41 Comments Measured under the Linux OS Programmer s Guide Page 63 of 63
33. 2 operational modes digitizer and averager controlled with the function AcgrsD1_configMode instrID mode 0 0 The value mode can be set to O digitizer or 2 averager The averager mode uses a number of additional configuration parameters which describe the requested averaging conditions Use the following short code fragment to configure an average of 1000 waveforms of 20000 data points with a dithering range of 15 ADC LSB s and a start delay of 128 samples for an AP100 Configure long channelNbr 0 nbrSamples 20000 nbrWaveForms 1000 long ditherRange 15 trigResync 1 long startDelay 128 stopDelay 0 AcgrsD1 _configAvgConfig instrID channelNbr NbrSamples amp nbrSamples AcqrsD1_configAvgConfig instrID channelNbr NbrWaveforms amp nbrWaveForms AcqrsD1_configAvgConfig instrID channelNbr DitherRange amp ditherRange AcqrsD1_configAvgConfig instrID channelNbr TrigResync amp trigResync AcqrsD1_configAvgConfig instrID channelNbr StartDelay amp startDelay AcqrsD1_configAvgConfig instrID channelNbr StopDelay amp stopDelay Comments The value channelNbr is usually 0 However for AP240 AP235 Signal Analyzer platforms it can take on the value of the desired channel for some of the parameters When in averager mode the following digitizer parameters are ignored delayTime of the function AcqrsD1_configHorizontal
34. 20 lower 3 The circular buffer analysis overhead time Ovhdpige is 2 500 us Pentium CPU speed in MHz Thus for a 250 MHz Pentium Ovhdpuffer is 10 us and for a 500 MHz Pentium 5 us Programmer s Guide Page 60 of 63 4 An Extra number of data samples must be transferred to the host computer with the memory image It depends on the sampling interval in ns and on the digitizer type Here are some rough values Extra Type 300 sampInterval 98 digitizers with lt 1 GS s maximum sampling rates 300 sampInterval 194 digitizers with 2 GS s maximum sampling rates or DC271 FAMILY instruments set for a combine channel mode allowing 2 GS s 300 sampInterval 386 DC271 FAMILY instruments set for a 4 GS s combine channel mode 5 The copying time Cpy per 8 bit sample is 5 us Pentium CPU speed in MHz Thus for a 250 MHz Pentium Cpy is 0 02 us and for a 500 MHz Pentium it is 0 01 us Benchmarks were run on 266 and 550 MHz Pentiums running under Windows 98 and NT The observed transfer times agreed with the formula within better than 20 e dataType 3 Add the conversion time T for conversion from ADC codes to Volts to T or T respectively T M N Conv where Conv is the conversion time per sample in microseconds It is 35 us Pentium CPU speed in MHz Thus for a 250 MHz Pentium Conv is 0 14 us and for a 500 MHz Pentium 0 07 us 4 2 Examples A DP210 in a 800 MHz Pentium T
35. 8 internal trigger sources 4 external trigger sources and 4 for the value of nbrModules Thus nbrIntTrigsPerModule would be 2 and nbrExtTrigsPerModule would be 1 as expected for a DC240 Internal triggers are associated to the input channels and follow the same numbering rules External triggers follow similar rules i e extTrig 1 corresponds to external trigger 1 of the first module extTrig 2 corresponds to external trigger 2 of the first module if nbrExtTrigsPerModule gt 1 or to external trigger 1 of the second module etc The externalTrigger 2 is the name used for the PXI Bus Star Trigger The functions AcqrsD1_configTrigSource and AcqrsD1_getTrigSource use the explicit trigger channel number with the internal trigger channel running from 1 to nbrIntTrigs and the external trigger running from 1 to nbrExtTrigs Note that 0 is an invalid trigger source resulting in an error code The functions AcqrsD1_configTrigClass and AcqrsD1_getTrigClass encode the trigger source in a 32 bit source pattern 31 30 20 29 16 19 5 15 4 3 2 1 0 Ext 1 Ext2 Other Ext Trigs Module Other Int Trigs In 5 In4 In3 In 2 In 1 0 IN 1 Internal trigger channel 1 1 IN2 Internal trigger channel 2 2 4 IN 3 IN 4 IN5 Internal trigger channels 3 4 5 5 15 OTHER INT Other internal trigger channels within a module up to 16 TRIGS 16 19 MODULE Module Number running from 0 to nbrModules 1 In single digit
36. ACQUISITION This method combines low CPU usage with very good response time The function enables the instrument s end of acquisition interrupt and sets up a semaphore that waits for this interrupt It then releases the thread by going to sleep thus letting other threads of the application or other applications use the CPU time The function returns as soon as the interrupt occurs or when the timeout expires The equivalent of the above for a Time Counter would be ViStatue status long timeOut 100 in ms status AcgrsT3 waitForEndOfAcquisition instrumentID timeOut if status ACQIRIS ERROR _ACQ TIMEOUT timeout stop status AcgrsT3 stopAcquisition instrumentID We recommend using AcqrsXX_waitForEndOfAcquisition since it is the most efficient method The interrupt latency is of the order of several us and no CPU time is wasted Programmer s Guide Page 31 of 63 3 9 4 Stopping Forcing a D1 style Acquisition The previous section shows a case where an ongoing acquisition must be stopped typically because there is no trigger Also in some situations you may want to use the digitizer to generate a system trigger under software control If you still would like to have a valid snapshot of the current input signal you should generate a trigger signal by software with the function AcqrsD1_forceTrig or AcqrsD1_forceTrigEx Typically the acquisition does not stop immediately since the digitizer may continue
37. AcqrsD1_readData for readMode 0 T M Ovhdpy M N Xfr e AcqrsD1_readData for readMode 1 ReadModeSeqW T Ovhd pu M Ovhd M N Extra Xfr M N Cpy with the following definitions M Number of segments N Number of samples per segment Xfr Transfer time per sample in ps typically 0 01 Ovhd py DMA overhead time per segment in us Ovhd Circular buffer analysis overhead time per segment in us Extra Number of overhead data points per segment Cpy Time to copy a sample in us The formulas above assume that M and N correspond to the number segments and samples set with the function AcqrsD1_configMemory If fewer segments or samples are transferred the timing might be somewhat less favorable than estimated by the formula 1 The transfer time Xp is typically 0 009 to 0 01 us 9 10 ns per 8 bit sample for digitizers directly inserted on the PCI bus of the host computer or connected through the SBS Bit3 interface Acqiris model number IC200 If a digitizer is connected through the National Instruments MXI 3 interface Xj is typically 0 012 us 12 ns Of course these times would get larger if there was considerable additional I O traffic on the PCI bus 2 The DMA overhead time Ovhdpma is approximately 50 000 usec Pentium CPU speed in MHz Thus for a 250 MHz Pentium Ovhdpma is 200 us and for a 500 MHz Pentium it is 100 ps With applications running under Windows 95 Ovhdpma has been observed to be
38. In many applications it can be ignored Refer to section 3 13 HORIZONTAL PARAMETERS IN ACQUIRED WAVEFORMS for a detailed explanation of horPos Return values have to be interpreted in the same way as for the other readout functions e Refer to the section 3 14 SEQUENCE ACQUISITIONS for detailed explanations on the interpretation of segDesc gt timeStampLo Hi e Itis important to zero the unused parameters at the end of the readPar structure An incorrect value of flags can be very confusing 3 10 2 Reading Sequences of Waveforms In certain situations see APPENDIX A ESTIMATING DATA TRANSFER TIMES it can be more efficient in time to read Sequence Waveforms with readMode 1 ReadModeSeqW This mode transfers all of the data from the digitizer to the local memory in a single DMA as opposed to calling AcqrsD1_readData many times thus using a transfer per segment The price to be paid is a higher memory requirement It can also be used to transfer blocks of segments in the case of very large memories For dataType 0 or 1 the amount of memory needed in bytes is Programmer s Guide Page 35 of 63 arraySize gt segmentOffset nbrSegments 1 dataType 1 with arraySize gt nbrSamplesNom currentSegmentPad nbrSegments 1 dataType 1 and segmentOffset gt nbrSamplesInSeg where e thecurrentSegmentPad depends on the acquisition configuration and can be determined using the following call Acqrs_getInstrument
39. Info instrID TbSegmentPad amp currentSegmentPad e the nbrSamplesNom is the nominal number of samples to record and may be different than what was asked for It can be determined using the following call AcqrsD1_getMemory instrID amp nbrSamplesNom amp nbrSegments e the nbrSegments can either be taken from the result given just above or it can be freely reduced to a smaller value in the case of a partial read of the data You have to make sure that you ask for this information after the acquisition configuration has been established This is the case after an acquisition has been completed with the new configuration Similarly for dataType 3 the amount of memory needed in bytes is arraySize gt 8 segmentOffset nbrSegments 1 with segmentOffset nbrSamplesInSeg and arraySize gt 8 segmentOffset nbrSamplesNom currentSegmentPad nbrSegments dataTypeADC 1 where dataTypeADC is 0 for the 8 bit instruments and 1 otherwise The following code can be used for reading a waveform sequence in 8 bit representation Programmer s Guide Page 36 of 63 long nbrSegments 10 long nbrPoints 1000 char dataArrayP long currentSegmentPad long nbrSamplesNom nbrSegmentsNom AqReadParameters readPar new AqReadParameters AqDataDescriptor dataDesc new AqDataDescriptor AqSegmentDescriptor segDesc new AqSegmentDescriptor nbrSegments readPar gt dataType 0 0 byte re
40. Point o 1 078E6 9 timeStampLo 3797121082 timeStampHi 1 SampTime 2 500E 9 VGain 7 63E 5 voffset 0 00 NbrSegments 2 Nbr vgwforms o reserved1 9 881E 324 reserved2 0 000E 0 reserved3 This VI demonstrates how to use some of the basic components of the AqDx Acqiris Digitizer Driver It finds and initializes a digitizer sets the basic parameters according to the controls on the front panel and then acquires one waveform Note that the front panel controls should be set to their desired values before the VI is run 2 3 3 AqDx Example Scope VI AqDx Example Scope vi File Edit Operate Tools Browse Window Help Digitizers Horizontal Settings Vertical Settings error out PCI INSTRI ee z a Trigger Setti x Trig Source Trig Channel Trig Slope a Positive TrigLevel1 TrigLevel2 Trig Coupling 0 000 30 000 Dc 2200 Sampling Interval 312 50E 9 Delay Time 0 00c 0 al E Internal Number of Segment Number of Samples Full Scale 95 000 Offset 0 00 Coupling SDC 1 MOhm Bandwidth Sho bandwidth limit Acquired Waveform limited to 10 segments 0 4 1 1 1 1 1 0 0E 0 2 0E 7 6 0E 7 8 0E 7 1 0E 6 1 4 0E 7 1 1 1 1 2 6 1 4E 6 1 6E 6 Gu Ea Ar FUP 3 eo Seg 0 Seg 1 Seg 2 Seg 3 Seg 4 Seg 5 Seg 6 Seg Seg 8 Seg 9 1 1 1 8E 6 2 0E 6 j This VI presents a basic interactive virtual oscill
41. ProcessingO int Processing readout AutoSwitch O S Description Software implementation 0 The software configures the mode the acquisition parameters and the readout AcqrsD1_configMode AcqrsD1_configAvgConfig 1 The software starts the first acquisition AcqrsD1_acquire instrID 2 The software sets the AutoSwitch semaphore To ensure the shortest response time this arming function should be done on the order of 10 20 us before the expected acquisition end AcqrsD1_processData instrID processType 1 processType 0 is used for SSR amp Peak 1 2 3 or 4 are for AP101 AP201 or Peak 3 When the acquisition has finish the FPGA automatically switches the banks starts a new acquisition a new processing and clears the AutoSwitch semaphore 4 Once the software receives the ProcessingEnd interrupt it can start the readout status AcqrsD1_waitForEndOfProcessing instrID timeout AcqrsD1_readData instrID channel amp readParams waveformArray amp wfDesc amp segDesc Go to 2 to continue Here is a sample bit of code showing this principle Programmer s Guide Page 33 of 63 status AcqrsDl1_acquire instrID Start the acquisition processType 0 for loop forever status AcqrsDl_ processData instriID processType 1 status AcqrsD1 waitForEndOfProcessing instrID timeout status AcqrsD1 readData in
42. Windows CVI and build the project e Note that you should insert the lines include AcqirisImport h and either include AcqirisDlImport h include AcqirisT3Import h Programmer s Guide Page 7 of 63 at the beginning of every file that will access Acqiris Device Driver functions e The project should include the AqDrv4 lib file 2 3 LabVIEW The AqXX Acqiris Digitizer driver for LabVIEW conforms to National Instruments Instrument Driver Standard If LabVIEW is installed on the target machine when the Acqiris software is installed the AqXX driver interfaces will be copied to the LabVIEW n Instr lib directory The driver function VI s can then be found on the Functions palette block diagram Instrument Drivers subpalette There is also a Getting Started VI as well as some example VI s The standard API help file is available from within LabVIEW The Revision Query VI gives information on the current version There are actually many llb files AqBx llb AqTx Ilb and AqDx llb containing the routines shown below The AqDx_obs llb has deprecated but still usable routines Under LabView8 the three families discussed above have been placed into 3 projects Each project contains Examples Private and Public Folders The project folder also contains an Acqiris Xx Readme html giving version information As an example the Tx project looks as shown below File Edit View Project Operate Tools Window Help lS x AA FR elo
43. XZ130 AGILENT ACOIRIS PROGRAMMER S GUIDE E Agilent Technologies Programmer s Guide ZM020150E Rev E June 2007 The information in this document is subject to change without notice and may not be construed in any way as a commitment by Agilent Technologies Inc While Agilent Technologies makes every effort to ensure the accuracy and contents of the document it assumes no responsibility for any errors that may appear All software described in the document is furnished under license The software may only be used and copied in accordance with the terms of license Instrumentation firmware is thoroughly tested and thought to be functional but it is supplied as is with no warranty for specified performance No responsibility is assumed for the use or the reliability of software firmware or any equipment that is not supplied by Agilent Technologies Inc or its affiliated companies Any versions of this manual which are supplied with a purchased product will be replaced at your request with the latest revision in electronic format At Agilent Technologies we appreciate and encourage customer input If you have a suggestion related to the content of this manual or the presentation of information please contact your local Acqiris representative or Acqiris Technical Support support acqiris com or come visit our web site at http www acgiris com Trademarks product and company names listed are trademarks or trade names of their respect
44. adPar gt readMode 1 1 sequence waveform readPar gt nbrSegments nbrSegments readPar gt firstSampleInSeg 0 readPar gt segmentOffset nbrPoints readPar gt firstSegment 0 readPar gt nbrSamplesInSeg nbrPoints readPar gt flags 0 readPar gt reserved 0 readPar gt reserved2 ll O a sa a Ss 5 readPar gt reserved3 status Acqrs_getInstrumentInfo instrID TbSegmentPad amp currentSegmentPad in this case the next call doesn t have any surprises status AcgrsDl getMemory instriID nbrSamplesNom nbrSegmentsNom readPar gt dataArraySize nbrSamplesNom currentSegmentPad l nbrSegments here we show the malloc explicitly dataArrayP char malloc readPar gt dataArraySize readPar gt segDescArraySize sizeof AqSegmentDescriptor nbrSegments status AcgrsDl readData instrID channel readPar dataArrayP dataDesc segDesc Comments The explicit malloc call will normally not be repeated for every acquisition Obviously a larger than needed allocation is perfectly acceptable Also any space allocated this way ought to be returned to the heap at some point 3 10 3 Averaging Waveforms in a Digitizer The driver includes 4 functions provided to improve performance when averaging waveforms The first pair of functions AcqrsD1_averagedData for any digitizer and the older AcqrsD1_averagedWform for 8 bit digitizers only are meant only for sin
45. alues for the gates can be defined during the acquisition process They will become effective after the next call to AcqrsD1_processData or AcqrsD1_acquire Here is some sample code long g_gateLengthSum 3 long g_lastGate 3 long channel 1 gate 1 AcqrsD1_configAvgConfig instrID channel GateType amp gate you can define up to 4095 gates GatePos and GateLength must both be multiples of 4 AqGateParameters configSetupData 100 long configObj SSR Default long gateSize 1000 this will be the size we want to read g_gateLengthSum channel 0 g_lastGate channel 1 a very simple example for int g 0 g lt g lastGate channel g the first gate starts with the first point configSetupData g GatePos g gateSize configSetupData g GateLength gateSize g_gateLengthSum channel configSetupData g GateLength 8 status AcqrsDl_ configSetupArray instrID channel configObj g_lastGate channel configSetupData For threshold gate readout you have to define the threshold value in volts Data values greater than this will be selected for readout If desired you can use AcqrsD1_configAvgConfig with the InvertData parameter to choose data values less than the threshold In addition you can define the number of data values before and after each selected value that you always want to see This number is in the range 0 to 16 However the value will always be rounded up to the next h
46. ame will be referred to as the deviceIndex The API contains a function Acqrs_getDevTypeByIndex to allow you to determine the family of an instrument before actually initializing it If there are several instruments in the system the order in which they are found is not obvious It depends on the Windows 2000 XP Configuration Manager implementation on the PCI bus topology in your computer and possibly on the BIOS 3 2 2 PCI Identification by Serial Number All Acqiris instruments are labeled with a unique serial number For PCI digitizers you will find it on the front panel and for CompactPCI instruments it is on the right injector ejector handle This same serial number is coded into an on board EEPROM that is read by the Device Driver upon initialization You can therefore ask to initialize a specific instrument by specifying its serial number ViSession instrumentID Acgrs InitWithOptions PCI SER10047 VI_FALSE VI_FALSE o amp instrumentID Note that the serial number must be contiguous to the keyword SER leading zeros are accepted 3 2 3 PCI Identification by Bus Slot Number While initialization by serial number is easy to implement it has the drawback that anytime an instrument is replaced by another one e g if a failure occurred the program has to be modified The Acqiris API offers the possibility of specifying the logical position of the device at initialization ViSession instrumentID Acgrs InitWwith
47. arams nbrSegments 1 readParams firstSamplelnSeg 0 readParams segmentOffset nbrSamples readParams firstSegment 0 Read first segment readParams nbrSamplesInSeg nbrSamples readParams dataArraySize sizeof waveformArray readParams segDescArraySize sizeof AqSegmentDescriptorAvg readParams flags 0 readParams reserved 0 readParams reserved2 0 0 readParams reserved3 0 0 AcqrsD1_readData instrID channel amp readParams waveformArray amp wfDesc amp segDesc Note If you call a readout function while the acquisition mode is set to digitizer it will return the last acquired single waveform possibly with some unpredictable results Note The raw sums can be read directly with a different function call see next section The relationship between Volts and the raw sum is expressed by the following formula sum i volts i offset FS 2 0 256 nbrWforms FS with the following definitions sum i 32 bit integer sum at position i unipolar i e 0 or positive volts i floating point voltage at position i as returned by the code fragments above offset offset in Volts as set with AcqrsD1_configVertical Programmer s Guide Page 38 of 63 FS full scale range in Volts as set with AcqrsD1_configVertical nbrWforms number of summed waveforms The value of nbrWforms must be known i e if the averaging process was interrupted before reaching the requested number of wavefo
48. ativePeakPos amp waveformArray 4 8 i Programmer s Guide Page 46 of 63 3 11 T3 style Data Readout For the reading of timer data the AcqrsT3_readData routine should be used Control of the read parameters is passed through the input structure AqT3ReadParameters The output format is determined by these values as well as the type of module in use TC890 TOF modules use a direct read out of the modules data for maximum throughput The PC does not have to analyze the data coming from the module The data are packed into 4 byte timer hits for each signal TC840 modules have a two phase readout The Acqiris driver software in the PC analyzes the raw data as read from the modules to derive the final timer results These are presented in double floating point format or an integer count of the time in the specified time granularity of the module The TC890 data are coded on 32 bits as described below This includes 31 Event on the channel to 6 time relative to the common channel event Event on the common input each common event are numbered even the common event that are lost if the internal Buffer is Full Aux IO Event Marker Switch marker Overflow Indicates the time value is not good because the real time counter reached its maximum value When the data is a marker this bit is also set 1 if 30 28 0 to 6 gt channel overflow if 30 28 7 gt marker 30 28 DataType Type of the current data Com
49. ature a timestamp in order to measure the time between the triggers of consecutive segments in the same acquisition In fact the timestamp counter is started when the Sequence acquisition is started and keeps counting during the entire sequence The difference between the timestamps of any pair of not necessarily adjacent segments is the time between their respective triggers The timestamp value is returned as a 64 bit integer in units of picoseconds with a resolution identical to that of the trigger time interpolator see the appropriate product User manual The waveform readout function AcqrsD1_readData returns the timestamp value as 2 32 bit values In order to do time differences you should transform them into a 64 bit integer e In Visual C C use the 64 integer __int64 as follows _ int64 timeStamp timeStampHi timeStamp timeStamp lt lt 32 unsigned long timeStampLo Arithmetic operations between such integers can be done as with shorter integers You also can convert a timestamp difference to an extended floating point number and do arithmetic operations as with other variables double deltaTime double timeStamp previousStamp e In Visual Basic use a decimal Variant variable as follows Const Twol6 As Variant 65536 Const Two32 As Variant Twol6 Twol6 Dim timeStamp As Variant previousStamp as Variant Dim timeDiff as Variant xStampLo as Variant If tStamplo lt 0 Then xStampLo Two32 Ab
50. ber of visible ones The helper functions take such memory overheads into account when advising you on the recommended sampling interval and number of samples You are free to ignore the advice but the system is likely to adapt your setup values if the requested number of samples does not fit the available memory Specifying the value 0 for delayTime sets the trigger point to the beginning of the waveform A negative value corresponds to pre trigger a positive one to post trigger Refer to the section3 12 TRIGGER DELAY AND HORIZONTAL WAVEFORM POSITIONfor a detailed explanation of the use of delayTime For DC coupling the trigger levels in FS as needed by AcqrsD1_configTrigSource can be calculated as follows TriggerLevelPercent 100 TriggerLevelVolts vOffset Fsrange The granularity of a trigger value setting is limited by the hardware that uses an 8 bit DAC covering somewhat more than the desired range To set the external trigger range for a DC271 FAMILY a 10 bit FAMILY module or an AP240 AP235 signal analyzer platform add a call to AcqrsD1_configVertical with channel 1 before the call to AcqrsD1_configTrigSource Programmer s Guide Page 22 of 63 e The DP1400 dual source pattern triggers can be activated by calling the function AcqrsD1_configTrigClass with an appropriate TrigClass and a sourcePattern indicating the two desired sources 3 4 Configuring Averagers 3 4 1 Basic configuration The averagers have
51. c needed to efficiently execute several crucial functions For Windows and Linux users they will be automatically programmed at startup before calibration The standard initialization using Acqrs_init can be used The name for the FPGA program file is a synthesis of model FPGA destination and option information The file name suffix is always bit The automatic initialization mentioned above will load the FPGA files as follows e For the first time inititalization of a module needing an FPGA file the desired file will be searched for in the working directory of the application e Then the working directory will be searched for a file AqDrv4 ini e Finally the directory pointed to by the environment variable AcqirisDxDir will be searched for a file AqDrv4 ini e The AqDrv4 ini file should contain the name of a directory which will also be searched for the appropriate FPGA files Here is a typical example of its contents Acqiris fpgaPath C Program Files Acqiris firmware GeoMapPath C Program Files Acqiris bin The GeoMapPath entry will be described later in this chapter e The final path used will be remembered and used for all subsequent demands for this module In particular this applies if AcqrsD1_configMode is used to change functionality Additional VxWorks Instructions For VxWorks users the normal mechanism for finding the FPGA bit files will not work the driver has to be told explicitly where to find them This p
52. cording but waits until a trigger signal is received Due to some circuit delays the waveform recording starts approximately 20ns after the receipt of the trigger signal Furthermore the first data points may be invalid For the DC271 family this means that the first 8 ns worth of data should be ignored for sampling rates 4 GS s gt SR gt 500 MS s and the first 4 ns 16 points for SR 4 GS s 3 18 3 Sequence Wrap The normal operation of the digitizer requires that it stop recording waveforms when the pre defined number of segments has been acquired Thus nbrSegments triggers are needed to acquire the requested number of segments into the same number of different memory sections After the acquisition has terminated all of the waveform segments are finally available for readout The Sequence Wrap mode also pre defines the desired number of different memory sections but it permits a larger number of triggers After the first nbrSegments waveform segments are acquired the digitizer wraps around to the first memory segment and keeps on recording waveforms This sequence can go on indefinitely since no hardware condition will stop it The only way to terminate this infinite loop is to stop it with the function AcqrsD1_stopAcquisition This mode is useful when only the last N out of many occurrences of a signal are of interest E g if you search for a rare event out of many occurrences and you only can determine its interest
53. cqrsD1_readData instrID channel amp readParams waveformArray amp wfDesc amp segDesc The returned data values in waveformArray are unipolar i e the raw ADC values are coded as values between 0 and 255 so that the summed data values may run between 0 and 255 N N number of waveforms in the sum 3 10 5 Reading a RT Add Subtract Averaged Waveform from an Averager This case is significantly different than the normal averager case described above The raw sums now have to be considered as signed values The relationship between Volts and the raw sum is expressed by the following formula sum i volts i 256 nbrWforms FS with the same definitions as before However the user has to understand if the final result corresponds to the desired signal or just half of it Programmer s Guide Page 39 of 63 3 10 6 Reading SSR Analyzer Waveforms 3 10 6 1 SSR Mode Readout Data Format In all cases data values are returned in the range 128 127 The relationship between Volts and the raw data is expressed by the following formula data i volts i offset 256 FS with the following definitions data i 8 bit signed ADC value at position i volts i floating point voltage at position i as returned by the code fragments above offset offset in Volts as set with AcqrsD1_configVertical FS full scale range in Volts as set with AcqrsD1_configVertical In all cases you must readout the entire acquisition You
54. d in This Manual The following conventions are used in this manual This icon to the left of text warns that an important point must be observed WARNING Denotes a warning which advises you of precautions to take to avoid being electrically shocked CAUTION Denotes a caution which advises you of precautions to take to avoid electrical mechanical or operational damages NOTE Denotes a note which alerts you to important information Italic text denotes a warning caution or note Bold Italic text is used to emphasize an important point in the text or a note mono text is used for sections of code programming examples and operating system commands Certain features are common to several different modules For increased readability we have defined the following families DC271 FAMILY DC135 DC140 DC211 DC211A DC241 DC241A DC271 DC271A DC271AR DP214 DP235 DP240 AP FAMILY AP240 AP235 AP100 AP101 AP200 AP201 12 bit FAMILY DC440 DC438 DC436 DP310 DP308 DP306 10 bit FAMILY DC122 DC152 DC222 DC252 DC282 1 4 Warning Regarding Medical Use The Agilent Technologies Acqiris cards are not designed with components and testing procedures that would ensure a level of reliability suitable for use in treatment and diagnosis of humans Applications of these cards involving medical or clinical treatment can create a potential for accidental injury caused by product failure or by errors on the part of the user These cards are not intended to be a subs
55. dinates for the data If you need to know the segment time stamps you can read the gated data If the user or threshold gate parameters are set appropriately the amount of unwanted data can be minimized 3 10 7 4 Reading the histogram The accumulated histogram can be read out using readMode 9 ReadModeHistogram The dataType and dataArraySize must be selected to correspond to the size of the histogram and its bins The waveform descriptor structure contains the value actualDataSize giving the total number of data bytes read The individual histogram bins will be able to contains accumulated sums of either 2 32 as ViUInt32 or 2 16 as ViUInt16 Histogram bin is 32 bits wide 31 0 Bin0 Histogram bin is 16 bits wide 31 16 15 0 Bin 1 Bin 0 3 10 8 Reading AP101 AP201 Analyzer Waveforms 3 10 8 1 Reading a Buffered Waveform Sequence This section concerns AP101 AP201 Analyzers ONLY In normal mode you may read the acquired waveform s in the same way as with any other digitizer as described in the section 5 14 Data Readout in the Standard Manual In buffered mode you must use the functions AcqrsD1_readData to read out the accumulated waveform sequence as a single data record E g if you configured nbrSamples 5000 and nbrSegments 800 you should specify segmentNumber 0 and nbrSamples 40007000 Before reading the buffered data you must switch to the other memory bank Typica
56. ding to the expected acquisition time but the loop time depends on the CPU speed B More Efficient Polling use this code fragment to release the polling thread for short periods ViBoolean done 0 long timeoutCounter 100 while done amp amp timeoutCounter gt 0 AcqrsD1_acqDone instrID done poll for status or AcqrsT3_acqDone instrID amp done the Time Counter equivalent Sleep 1 if timeoutCounter lt 0 timeout stop acquisition STOP ACQUISITION This code puts the polling thread to sleep for periods of 1 ms at a time letting other threads of the application or other applications use the CPU time Setting the timeout counter to 100 means that a total timeout period of 100 ms is expected NOTE This method still has some drawbacks e depending on the operating system the Sleep method often has a granularity of 10 ms or more rounding any smaller number up to this minimum value e the response time of the application to the end of acquisition is 50 of the sleep time on average With a granularity of 10 ms the mean latency is therefore 5 ms Thus no more than 200 waveforms per second could be acquired because the application wastes time waiting for the acquisition to terminate C Waiting for Interrupt VisStatus statis long timeOut 100 in ms status AcgrsDl waitForEndOfAcquisition instriD timeout if status ACQIRIS ERROR_ACQ TIMEOUT timeout stop STOP
57. e second call you must specify simulate TRUE without any spaces The device driver creates a simulated device of your choice The resource name string is always of the form PCI aannn where aannn is a valid instrument module name The simulation options will apply to all subsequent calls to Acqrs_InitWithOptions until they are reset with Acqrs_setSimulationOptions 3 2 11 Terminating an Application For an orderly shut down of your application we recommend the following sequence Stop the instruments for long i 0 i lt nbrInstruments itt status AcgrsDl stopAcquisition instrumentID i or status AcqrsT3_ stopAcquisition instrumentID i Acgrs closeAll Stopping the acquisition of all instruments ensures that there is no further activity that could for example generate an interrupt The function Acqrs_closeAll shuts down the driver components in the correct order and thus helps avoid crashes of the application during closing 3 3 Device Configuration As a general rule it should be remembered that new values to be used by the modules as set with the AcqrsXX_config functions are remembered by the driver software but not immediately acted upon They will only really be loaded into the instrument s registers at the beginning of an acquisition when AcqrsXX_acquire is called At that time all necessary changes will be made and depending on the type of changes the driver will force itself to
58. e that contains the Visual Basic version of the interface to the Acqiris driver dll s installed in the System directory This file is needed for all Visual Basic projects involving Acqiris digitizers Programmer s Guide Page 13 of 63 2 The AcqirisShow8 frm or AcqirisShow12 frm file that contains all the basic functionality of the sample program such as initialization acquisition control and display 3 The DevCtrlForm8 frm or DevCtrlForm12 frm file with the code for a dialog box for the control of a complete digitizer The Visual Basic sample program is capable of managing several Acqiris digitizers attached to the computer and of displaying one channel of one digitizer at a time If no digitizer exists on the computer it initializes 3 simulated digitizers in Sub Form_Initialize While it has enough functionality to permit a fairly complete operation of a digitizer many possible features were left out in order to keep the program simple to understand In order to run the Visual Basic sample program you must have installed the Visual Basic Version 5 0 or 6 0 but not NET e Start Visual Basic e Use the menu File gt Open Project to point to the AcqirisShow1 vbp project file in the AcqirisLive VB directory and choose Open e After the project is loaded use the menu Run gt Start or F5 to start executing the project A waveform display window should pop up displaying a real or simulated waveform e Use the button D
59. eecaeeeneeeeeeeeeeeeneeeseeeseenaees 42 3 11 T3 style Data ReadoUt iii de EE 47 3 12 Trigger Delay and Horizontal Waveform Position ccccccceessesscessceeeceseceseesecesecaecaecaeecaeeeaeenseenseeneeees 47 3 13 Horizontal Parameters in Acquired Waveforims ccccccsccssecsseesseeseeesceeseesecesecesecsaecaecaeecaeeeseeeseenseeerenes 48 3 14 Sequence Acquisitions 2 aci 49 3 15 PMI SEATINPS 50 25 Shot cease SE Sods wens ce fdea Sedat Poa Stic Se eSSe oSeedees da dabede Boa seag ud tice tontbs owes dhceds tet ts Soatiee cs oe 49 3 16 Extemal Clock amd Reference 43 fi ies feet a hie elect hha E EREA 50 FLO External Reference ii it Aaa eat 50 3 16 2 External Clock ComtinuouS ccccccssesssesscessceseesseeeeceecesecnsecsaecsaecnaecaaecaeecaeeeaeseseseeeeeeseneeeneseneeeseeaees 51 3 16 3 External Clock Start Stop ccccesccssecseesseeseeeseesseeeeeeeessccneecaeceaecnecaeceaeceaecaaecaeecaeeeneseneeeeeseneenaeenaees 53 3 17 ASBUS Op leet hank sis Ge CHRON RL eee AER o o a a eee 54 3 17 1 Channel Numbering with ASBUS ennist ee E e e as E e e R E 54 3 17 2 Trigger Source Numbering with ASBUS s sesessssessssresessesersreseesessteresseserseestestssteessestesteseesesseeeessesees 54 3 18 Special Operating Mods ia AERO di isa 56 SSI Frequency Countin dengena e wath nase Stes ever tanned Manan Aiea A TEN 56 3 18 24 Start on TEES O e O 57 3 837 Seguente Wrap dat a 57 3 19 Readout of Battery Backed up Memories
60. ent Temperature The temperature of an instrument can be obtained with the following code long temperature will be in degrees C Acara getIinstrumentinfo instrIib Temperature amp temperature When multiple digitizers are combined via ASBus to a Multilnstrument use the strings Temperature 0 Temperature 1 to refer to the individual modules NOTE The returned temperature value corresponds to the ambient temperature on the main printed circuit board typically near the timebase circuit It cannot represent all possible temperature values that are present on the circuit Values gt 60 C indicate that the circuit is near its operational limit and a cooling failure occurred or better cooling should be installed We recommend keeping the temperature as low as possible since a 10 C reduction in circuit temperature is expected to improve the mean time between failures MTBF by a factor of 2 We also recommend reading the temperature when the instrument is stopped The read operation may generate small signal perturbations through cross talk if it is executed while an acquisition is in progress Programmer s Guide Page 59 of 63 4 Appendix A Estimating Data Transfer Times The time to transfer a waveform may be a significant part of the execution time of a program and thus becomes an important design consideration for new applications We present here a simple timing model with the aim of predicting the transfer time
61. first data point will be dataArray readPar indexFirstPoint and that this is not necessarily the first point given e The exact position of the first data point with respect to the time origin is a negative number horPos It is by definition in the range sampInterval 0 e The time between the trigger and the first data point hOffset need not be recorded since it can always be computed as delayTime horPos Note delayTime horPos lt delayTime by definition e In order to obtain a very stable image even in a highly zoomed display the user only needs to position the acquired data points with the aid of horPos by using the following formula for the x position of point i with respect to the left edge of the display x i horPos i sampInterval 3 14 Sequence Acquisitions For digitizers in Sequence acquisition mode multiple waveforms are acquired autonomously with a single start command AcqrsD1_acquire Whenever a trigger is received the current acquisition segment is normally terminated The digitizer then automatically initializes another acquisition into the next memory segment until all requested segments are filled 3 15 Timestamps The 10 bit Family of digitizers implements a timestamp to measure the time of the trigger for each acquisition segment These timestamps can be used to calculate the time between any two triggers for any pair of triggers over multiple acquisitions The other older Acqiris digitizers fe
62. gAvgConfig instrID channelNbr TrigResync amp freeRun AcgrsD1_acquire instrID long timeOut 1000 depends on conditions AcgrsD1_waitForEndOfAcquisition instrID timeOut Programmer s Guide Page 24 of 63 long nbrPoints Should be the current number of points long timeStampLo timeStampHi nbrReturnedSamples double horPos sampTime Read the Waveform directly to the Background buffer double bckGndWform nbrPoints AcgrsD1_readRealWform instrID 1 0 0 nbrPoints bckGndWform nbrReturnedSamples amp horPos amp sampTime amp timeStampLo amp timeStampHi Restore the settings of the averager AcgrsD1 configvertical instrib 1 fer offset coupl bwidth AcqrsD1_configAvgConfig instrID channelNbr TrigResync amp reSync Use the following code fragment to acquire a fixed pattern background assuming that the external trigger can be used and is already set const long channelNbr 0 double fsr offset long coupl bwidth reSync freeRun 2 AcgrsD1_acquire instrID long timeOut 1000 depends on conditions AcgrsD1_waitForEndOfAcquisition instrID timeOut long nbrPoints Should be the current number of points long timeStampLo timeStampHi nbrReturnedSamples double horPos sampTime Read the Waveform directly to the Background buffer double bckGndWform nbrPoints AcgrsD1_readRealWform instrID 1 0 0 nb
63. gate definition in section 3 5 2 Readout configuration Similarly you initiate an averaging operation by configuring the instrument parameters including those that control the averaging and then starting the combined acquisition averaging sequence The Averager module resets the accumulation buffers and then acquires the requested number of waveforms each preceded by a front panel trigger signal without any software intervention The AcqrsD1_acquireEx function allows an AP100 AP200 Averager to acquire additional data without resetting the accumulation Until the operation is terminated your application is free to execute other tasks There are several methods of detecting when the acquisition averaging operation has ended Finally you read the averaged waveform with the function AcqrsD1_readData as described below If you want to acquire several averaged waveforms under the same conditions there is no need to call the AcqrsXX_config functions again It is sufficient to execute a loop over the start wait read functions In principle a subsequent start will happen considerably faster than the first one that was required to load the full configuration 3 9 1 Starting an Acquisition Use the following line of code for starting an acquisition in a D1 style instrument AcqrsDl acquire instrID start the acquisition or the following line of code for starting an acquisition on a Time Counter AcqrsT3 acquire instrumentID sta
64. gation delays There can be at most 5 modules in the Multilnstrument ASBus 3U digitizers e The master module will be the rightmost of up to 3 modules The function Acqrs_getInstrumentData will return the information about the master module If you want control over which module is the master and in which order they should appear use the manual definition described in the next section 3 2 8 Manual Definition of Multilnstruments The function AcqrsD1_multilnstrDefine permits a manual definition of how to combine multiple digitizers with the ASBus It cannot be used for ASBus instruments Use a code fragment like the following one for the manual combination of digitizers ViSession instrumentID 10 idList 6 long nbriInstruments vistatus status ViString options cal 0 since calibration will be performed explicitly later status Acqrs_getNbrinstruments nbrinstruments Programmer s Guide Page 19 of 63 Initialize the digitizers for long 1 0 1 lt nbrinstruments i char resourceName 20 sprintf resourceName PCI INSTR d i status Acgrs InitWithOptions resourceName VI_FALSE VI FALSE options amp instrumentID i Now combine the first 3 digitizers in inverse order idList 0 instrumentID 2 idList 1 instrumentID 1 idList 2 instrumentID 0 ViSession multilInstrID ViSession masterIndex instrumentID 1 long nbriInList 3 status
65. ge of trigChan and or inputNbr 3 18 Special Operating Modes Some Acqiris digitizers offer alternative operating modes which are controlled with the function AcqrsD1_configMode The default state of any digitizer is mode 0 and flags 0 corresponding to the normal digitizer operation as described in the other sections of this manual 3 18 1 Frequency Counter This is an option available for the DC140 and DC135 digitizers It is implemented with a signal counter that counts trigger signals from the user requested channel A time counter generates the user programmed aperture time during which the measurement is performed The user requested signal channel has to be programmed for the expected signal characteristics the standard config functions should be used to set the full scale coupling offset and trigger threshold The HF trigger mode may be set by the driver software on the basis of the user supplied target frequency value In order to obtain the best results it is recommended to adjust the full scale and offset so that they span the expected input signal In addition the trigger threshold should be set to approximately the center of the signal voltage range Calls to AcqrsD1_configVertical and AcqrsD1_configTrigClass are needed If an external time base reference is desired AcqrsD1_configExtClock should be called If the totalize in gate functionality is desired the source of the gate must be set with the function AcqrsD1_configCont
66. gle channel single segment operation They average a predefined number of waveforms taking care of the acquisition loop internally The client must supply a working array dataArray or waveformArray for internal use and an accumulation array sumArray The accumulation array is reset automatically inside the function at the beginning of each call When the function returns successfully the accumulation array contains the sample by sample sum of the waveforms To get the average values the array elements must be divided by the number of acquisitions nbrAcq If for each acquisition the trigger does not arrive within the requested timeout after the beginning of the acquisition the function returns with an error code The second pair of functions AcqrsD1_accumulateData for any digitizer and the older AcqrsD1_accumulateWform for 8 bit digitizers only can be used for multi channel operation and can be called for each acquisition the user wants to accumulate It reads the waveform in the module and performs a sample by Programmer s Guide Page 37 of 63 sample accumulation in the client array Here again the client must supply a working array dataArray or waveformArray for internal use and an accumulation array sumArray The client controls the acquisition and must reset the accumulation array appropriately In both cases the allocation of the memory for the working array dataArray or waveformArray has been left to the client for perfo
67. guring the instrument parameters the measurement sequence is started with the function AcqrsD1_acquire This function returns before the measurement is terminated The user must wait until it is terminated with the functions AcqrsD1_acqDone or AcqrsD1_waitForEndOfAcquisition For the case of Totalize by Gate the program must stop the acquisition by making a call to the function AcqrsD1_stopAcquisition FC results can be readout with the function AcqrsD1_readFCounter The result is always a single double precision number whose units are those appropriate for the type of measurement chosen Programmer s Guide Page 56 of 63 3 18 2 Start on Trigger The Start on Trigger mode begins data recording only upon receipt of a trigger signal and stops after nbrSamples data points are acquired Not all digitizers are capable of this mode those that never have it are the DC110 DC240 DC265 DC270 and the 12 bit digitzers others DP105 DP106 DP110 DP111 DP210 DP211 DP212 can have it as an option only It is useful in the special case where the sampling rate is less than the maximum possible and where an optimum time correlation between the trigger and the sampling clock is required typically when averaging waveforms This mode also requires that the trigger is available before the waveform of interest In the Normal mode data recording begins at the time of arming with the function AcqrsD1_acquire The trigger occurs asynch
68. he DC135 DC140 DC211A DC241A DC271A DC271AR and 10 bit FAMILY e 1 V for the other DC271 Family digitizers the 12 bit Family the AC SC Analyzers the DP1400 and the AP Averagers and Analyzers e 2 V peak to peak for all other models The inputThreshold value should be set to the center of the signal 3 16 1 External Reference This external reference mode clockType 2 simply replaces the internal 10 MHz reference clock with an external one at the same or a similar frequency Alternatively for the DC135 DC140 DC211 DC211A DC241 DC241A DC271 DC271A DC271AR the AC SC and the 10 bit FAMILY the PXI 10 MHz System Clock can be used as the reference If you need a more precise timebase or want to ensure that the timebases of several modules are at exactly the same frequency you should use clockType 2 in the function and apply an external 10 MHz signal All other settings of the digitizer are exactly the same as with an internal reference clock If you need to sample at a rate that deviates from the nominal values you may apply an external reference signal with a constant frequency in the range of e 9 97 10 03 MHz for the DP1400 and the 10 bit FAMILY e 9 0 11 0 MHz for the 12 bit FAMILY e 9 0 10 2 MHz for all other modules You need to correct for the reference frequency difference in your application since the digitizer and the driver do not take the deviations into account NOTE A square wave with better than 5 ns r
69. he time stamps for the same segment are not necessarily the same for the two channels The command above works with the stamp of Channel 2 In this release if the function is called before the first acquisition has been started the value returned will be 0 It is possible to reset the time stamp using a hardware signal on the P1 or P2 connectors This can be done with a call like Long TSReset 1 Plcontrol eTSkesst status AcgrsD1 configAvgConfig instriID channel 3 6 Configuring Peak Analyzers Since Peak processing can be viewed as an additional form of processing after SSR acquisition please refer to the discussion in 3 5 Configuring SSR Analyzers for that part of process In addition you will have to Configure peak detection long numberOfTriggersPerSeg 50 numberOfSegments 1 double startDelta 0 1 validDelta 0 2 AcqrsD1_ configMode instrID 5 0 0 NbrRoundRobins NbrSegments snumberOfSegments StartDeltaPosPeakV ValidDeltaPosPeakV AcqrsD1_configAvgConfig instrID amp numberOfTriggersPerSeg AcqrsD1_configAvgConfig instrID AcqrsD1_configAvgConfig instrID amp startDelta SO Oo O AcqrsD1_configAvgConfig instrID amp validDelta Configure histogram long tdcMode 1 tdcDepth 1 tdcIncr 2 0 TdcHistogramMode amp tdcMode tdcType 1 AcqrsD1_configAvgConfig instrID AcqrsD1_configAvgConfig instrID AcqrsD1_configAvgConfig ins
70. host computer to terminate the acquisition and AcgqrsDl stopAcquisi tion inst rip AcgrsD1_readXXXWform instrID E E Note that the sampling rate and the time between bursts have no incidence on the configuration parameters of the digitizer 1 e they appear nowhere Example for Termination 2 if you wanted to acquire 5000 waveforms of 200 data points each you would write AcgqrsDl_configMemory instrIDb 100000 1 AcqrsDl_configExtClock tinstriD 4 threshold 0 0 0 0 0 AcgrsD1l_acquire instrID start the acquisition gt Generate 5000 bursts of 200 clock pulses at the required frequency At the end you need to generate 2 160 320 640 additional clock pulses AcqrsD1_waitForEndOfAcquisition instrID timeOut AcgrsD1_readXXXWform instrID 4 w y The 320 640 on 2 GS s or 1280 on 4 GS s digitizers extra clocks could be generated by 1 or more extra bursts of 200 clock cycles or a special burst There is no risk of overwriting the earliest data since the memory is not circular in this mode Comments valid for both termination mechanisms Programmer s Guide Page 53 of 63 gt Bb Although the function AcqrsD1_acquire sets it to the ready state the digitizer cannot actually record data while the external clock is idle The clock burst must start after the digitizer has been started and it must start in a very clean way i e the first pulse must be already well over the threshold and its width must be 1 ns
71. hrough module 0 then through modules 1 2 etc For Acqiris CC10x crates when a Multilnstrument is defined with AcqrsD1_multilnstrAutoDefine module 0 is always closest to the controller slot whereas with AcqrsD1_multiInstrDefine it corresponds to the first module in the initializing list The Acqiris CC121 crates have a different ordering please refer to the Acqiris CC121 CompactPCI Crate User Manual E g when combining 3 DC270 4 channel digitizers you would use channel number 10 in the function calls config get_MultiInput config get_Vertical and readChar RealWform if you wanted to refer to Input 2 of the third DC270 Channel numbering does not depend on which module is the actual clock or trigger master 3 17 2 Trigger Source Numbering with ASBus Acqiris digitizers do not necessarily have as many internal triggers as channel inputs nor exactly one external trigger You should retrieve for every MultiInstrument additional information with the following calls Programmer s Guide Page 54 of 63 Acqrs getInstrumentInfo instrID NbrinternalTriggers nbriIntTrigs Acqrs getInstrumentInfo instrID NbrExternalTriggers amp nbrExtTrigs Acqrs getInstrumentInfo instrID NbrModulesInInstrument amp nbrModules nbrintTrigsPerModule nbrIntTrigs nbrModules nbrExtTrigsPerModule nbrExtTrigs nbrModules In a Multilnstrument composed of 4 DC240 2 channel 2 GS s digitizers you would get
72. ighest multiple of 4 If two consecutive selected values are 32 or more samples apart a new gate block will be generated Otherwise the current block will be continued In all cases the data transferred will always be a multiple of 4 samples and it will start on a sample whose time position is a multiple of 4 Alternatively the number of data values before and the total number of values can be selected Furthermore a limit on the maximum number of gates per segment can be set Programmer s Guide Page 27 of 63 long channel 1 gate 2 AcqrsD1_configAvgConfig instrID channel GateType amp gate long preSamples 0 postSamples 0 maxGates 1 double threshold 0 0 in Volts long thresEnable 1 status AcgrsD1 configAvgConfig instrID channel PreSamples preSamples status AcgrsD1 configAvgConfig instriID channel PostSamples amp postSamples status AcqrsDl_ configAvgConfig instrID channel Threshold amp threshold status AcgrsDI configAvgConfig instrID channel NbrMaxGates amp maxGates 3 5 3 Time stamps The On board 10 MHz reference clock is used to increment a counter The value of the counter is stored after the trigger of each new segment The value of the counter can be read by the software as shown here double SSRtimeStamp Acqrs_getInstrumentInfo instrID SSRTimeStamp amp SSRtimeStamp Since each channel is controlled by its own FPGA t
73. igitizer Control to make a dialog box appear The top most control Digitizer permits the choice of one of several digitizers and to check how many were found If no physical digitizer was found the program initializes 3 simulated digitizers a DP110 DC240 and a DC110 with the 2MB option You can change the simulated digitizers in Sub Form_Initialize e The program is stopped by clicking on the Close button x on the upper right hand side of the waveform display window The waveform display window can be resized but the dialog box cannot The acquisition mode Norm really is another Auto mode with a slightly longer timeout period A real Norm mode without timeout would require a way for the user to regain control in situations where there is no trigger Simulated digitizers have fixed simulated input signals sine waves triangle waves or square waves that cannot be modified through the supplied API Note The programming advice in the rest of this manual is given for the C language interface However it is equally valid for Visual Basic Refer to the file AcqrsD1Interface bas for the correspondence between the Visual Basic and C language names of the Acqiris driver functions Note There is no VB support for Time Counter modules 2 5 MATLAB MATLAB is a very powerful environment to analyse and display data The interface from it to the Acqiris products offers simple direct access to the Acqiris driver An example is in the directo
74. ility O lt ata E f Star JO a MO la Q Q fay pan ed N onfig Config Config Queers uery ery Ltucry Close dy Eom pe en BESS y y 4 M Ro ES onfig Acq y LE 2 3 1 LabView 7 x 8 with old LabView programs If you have an existing LabView program you can still use it or develop futher under LabView 8 You can continue to use the VI s and libraries of the LabView 7 1 environment If you are still using the AqDx versions under LabView 7 x they will not immediately be found when you load your vi LabView will ask you which library should be used you should enter the name of the library of obsolete functions AqDx_obs llb Programmer s Guide Page 9 of 63 2 3 2 AqDx Getting Started VI ile Edit Operate Tools Browse Window Help gt Sjn 13pt Application Font 1 tor Tar 2 r i Channel BEBE y gi Trigger Settings Trigger Source Trigger Coupling TrigLevel1 TrigLevel2 Trigger Slope poo 0 000 FPositve Resouce Name PCI INSTRO Horizontal Settings Vertical Settings x2 l Number of Samples 200 Sampling Interval aso Delay Time a Internal Read Mode poc Acquired Waveform limited to 10 segments i error out dataDesc status code 2 source a0 1 ADF 1 12 sen Seg O Seg 1 Seg 2 Seg 3 Seg Seg5 Seg 6 Seg Seg 8 Seg 9 returnedSamplesPerSeg i 0 000E 0 200 AddrFirst
75. individual modules without ASBus connections It automatically searches for all sets of modules that are connected with ASBus and configures each such block as a single Multilnstrument As an alternative to automatic Multilnstrument definition you can initialize each module individually with the function Acqrs_InitWithOptions and then combine some of them with the function AcqrsD1_multiInstrDefine This method provides better control over which modules are combined and in what order at the expense of careful book keeping of which instrumentID s are available For details please refer to the section 3 2 8 Manual Definition of MultiInstruments Programmer s Guide Page 16 of 63 3 2 1 PCI amp VXI Identification by Order Found If you don t know which and or how many Acqiris instruments are present on the machine use this code fragment ViSession instrumentID 10 long nbriInstruments ViStatus status ViString options status Acqrs_getNbrinstruments nbrinstruments Initialize the instruments for long i 0 i lt nbrInstruments itt char resourceName 20 sprintf resourceName PCI INSTR d i status Acgrs initWithOptions resourceName VI_FALSE VI_FALSE options amp instrumentID i The resource name must be of the form PCI INSTRO PCI INSTR1 etc This is true in spite of the fact that all PCI cPCI and VXI instruments will be found The integer part of the resource n
76. ing Hints When programming an Acgiris instrument it is important to remember that the Acqiris driver must be freshly loaded this is usually automatic by any process that uses the modules This means that each process starts over with a completely clean view of the system and no knowledge of any previously determined calibration constants or settings Thus a calibration ought to be done before the modules are used for any acquisitions Of course the system may have to be recalibrated later if the temperature of the modules is changing Users cannot expect to control Acqiris modules with a succession of process invocations with each one executing a single command Only one process on a machine can have loaded the Acqiris driver at any given moment Most of the Acqrs and AcqrsXX driver functions are reentrant After initialization they are protected against multiple calls from different threads The unprotected routines are Acqrs_init Acqrs_initWithOptions Acqrs_getNbrInstruments Acqrs_close Acqrs_closeAll AcqrsD1_multiInstrAutoDefine AcqrsD1_multiInstrDefine AcqrsD1_multiInstrUndefineAll Be sure to read the comments on the functions and their parameters in chapter 2 DEVICE DRIVER FUNCTION REFERENCE of the Programmer s Reference Manual Another valuable source is the header files AcgirisInterface h AcqirisD1Interface h or AcqirisT3Interface h for C like environements or the equivalent bas or vb files for Visual Basic The examples below do
77. ions are protected against illegal or incoherent values Thus the system might adapt the values you ask for There are 5 query counterparts to these functions AcqrsD1_getHorizontal AcqrsD1_getMemory AcqrsD1_getVertical AcqrsD1_getTrigClass and AcqrsD1_getTrigSource which you can interrogate The function AcqrsD1_configTrigClass configures the trigger class control parameters of the digitizer For most Acqiris products the edge trigger class is the only class available For this class the available source patterns are Channel 1 through 4 or the external triggers The AcqrsD1_configTrigSource function configures the source parameters coupling slope and level as shown in the example above Notice that the functions AcqrsD1_configTrigClass and AcqrsD1_configTrigSource must always be used together in order to complete the setup of the trigger configuration Refer to chapter 2 DEVICE DRIVER FUNCTION REFERENCE of the Programmer s Reference Manual for a detailed description of these two functions The helper functions AcqrsD1_bestSampInterval and AcqrsD1_bestNominalSamples are sometimes useful for deciding on the nominal number of data points and the sampling interval to use for a given time window to cover If you ask for a nominal number of samples the system actually needs some additional samples for reasons of data alignment acquisition stop time overhead and other reasons In some cases the additional invisible samples can exceed the num
78. irst download the Low Level kernel mode VxWorks Device Driver file VxWorksDriverPClI out to the target machine followed by the VxWorks Driver file AcqirisVxWUMode out Finally you should download the VxWorks application GetStarted VxW out 2 6 3 Running the Program It is recommended that you follow the code with the debugger since it is the only way to see the response of the function calls immediately 2 7 Linux The AcqirisDemo program can simply be run from the AcqirisLinux directory by entering Demo AcqirisDemo The library usr lib libAqDrv4 so is compiled with either gcc 3 3 3 4 or 4 1 you need to have installed the desired version The Linux GetStarted sample program is provided ready to run It can also be created without the need of an additional development application e Enter the command cd usr src e Run make to compile and link the program e Note that the include and library paths are defined in the Makefile The GetStarted cpp file contains a simple user program which e has globally allocated buffers to achieve optimal readout performance e finds the Acqiris digitizers on the target machine e initializes the first or only one e configures some acquisition parameters and rereads them for checking e loops 100 times over a cycle that starts the acquisition waits for it to terminate reads the waveform Programmer s Guide Page 15 of 63 3 Programming an Acgiris Instrument 3 1 Programm
79. isetime should be used This is needed to avoid false or multiple transitions on a slower risetime signal Alternatively a gt 2 V amplitude signal could be used NOTE When using this capability please make sure that the module is correctly synchronized on the signal This might require adjusting the threshold If this is not the case the data will be useless and calibration can fail in rather obscure ways Programmer s Guide Page 50 of 63 3 16 2 External Clock Continuous The continuous external clock mode clockType 1 permits the application to the digitizer of a continuous constant frequency external clock in order to sample at an arbitrary frequency This mode uses normal triggering from the input signal or through the external trigger input We need to distinguish between first generation digitizers models DP105 DP106 DP110 DP111 DP210 DP211 DP212 DC110 DC240 DC265 DC270 second generation digitizers of the DC271 FAMILY models DC135 DC140 DC211 DC211A DC241 DC241A DC271 DC271A DC271AR DP214 DP235 DP240 the AP240 AP235 signal analyzer platforms the AC210 AC240 SC210 SC240 analyzers and the 12 bit FAMILY DC440 DC438 DC436 DP310 DP308 DP306 and third generation digitizers models DC122 DC152 DC222 DC252 DC282 DP1400 since their behavior in this mode is quite different AP200 AP201 AP100 AP101 Averagers and Analyzers are considered to be first generation modules The horizontal control paramete
80. ive companies Acqiris Headquarters Acgiris USA Acgiris Asia Pacific Agilent Technologies SA Agilent Technologies Inc Agilent Technologies 12 chemin des Aulx P O Box 2203 Australia Pty Ltd CH 1228 Plan les Ouates Monroe NY 10949 347 Burwood Highway Geneva USA Forest Hill VIC 3131 Switzerland Australia Tel 41 22 884 32 90 Tel 845 782 6544 Tel 61 3 9210 2890 Fax 41 22 884 32 99 Fax 845 782 4745 Fax 61 3 9210 5929 Copyright Agilent Technologies Inc June 2007 Programmer s Guide Page 2 of 63 CONTENTS 1 N INTRODUCTION curian aisin RE S E NNN REEE E N E ENERE 5 Ish Messageto TORS E E A E A T EA o dd E ne aloes 5 12 CW sing this ETTU E I dr E E E AA 5 1 3 Conventions Used in This Manual ec ccesccsssscsseescesceesecsseeeessccaeesecnevsecsasecesaecaessecneseccnaseneeaeeaseneeaeeatease 6 14 Warning Regarding Medical Usuarias Ge 6 NEO 6 1 6 Warranty and Repair Return Procedure Assistance and Suppott ccccceseeceeeceseceeceseceeceeenseeneeneeeereees 6 LIe System AMA cases aa a a a E EE A Era E ER 6 PROGRAMMING ENVIRONMENTS GETTING STARTED sesesesesesesesssesesessssseseseeessssosesosssesesesesesesesee 7 21 MA cit 7 22i LabWindows CV licita ee eee ds ede ed 7 DB LAD NN NANO 8 2 3 1 LabView 7 x 8 with old LabView programs ooooccccionnonnconnnoncconcnnnonnnonn nono non cnn nnnnn non n nn nn corn nnn ran nran ninia ninos 9 2 32 gt AQDx Getting Started Vai ida 10 2 33
81. izers this field must be zero In Multilnstruments the trigger source number must be broken into a module number and a trigger channel number within the module 20 29 OTHER EXT Other external trigger channels within a module up to 12 TRIGS 30 EXT 2 External trigger channel 2 31 EXT 1 External trigger channel 1 In future digitizers with trigger pattern capabilities several trigger bits could be set simultaneously However no trigger pattern capabilities between different modules can be coded i e only a single module in a MultiInstrument can be the trigger source although the source in the single module might be a pattern For these reasons the module number must be coded explicitly To translate a trigger channel number trigChan into a trigger source pattern use the following code a PESACH a gt 0 Internal Trigger long moduleNbr trigChan 1 nbrIntTrigsPerModule long inputNbr trigChan 1 nbrIntTrigsPerModule srcPattern moduleNbr lt lt 16 0x1 lt lt inputNbr else if trigChan lt 0 External Trigger trigchan trig chan long moduleNbr trigChan 1 nbrExtTrigsPerModule long inputNbr trigChan 1 nbrExtTrigsPerModule srcPattern moduleNbr lt lt 16 0x80000000 gt gt inputNbr Programmer s Guide Page 55 of 63 else PROBLEM Note that moduleNbr and inputNbr start from 0 An industrial strength implementation should contain some checks on the ran
82. layTime is defined with the value delayNbrSamples which only applies to external clock operation The actual delay value is easily computed as follows delay delayNbrSamples nbrSamples sampFrequency Example In a 1 generation module with an external clock running at 200 MHz if you wanted to acquire 2000 data points at 50 MS s with the trigger point at the end of the first quarter of the time window you would use the code AcqrsD1_configMemory instrID 2000 1 AcgrsD1 _configExtClock instriD 1 threshold 1500 2 0e 8 3 0e 7 7 AcgrsD1l_acquire instrID start the acquisition AcqrsD1_waitForEndOfAcquisition instrID timeOut The value of delayNbrSamples is 1500 because 500 points need to be acquired before and 1500 points after the trigger in order to position the trigger point at the 1 quarter of the time window Equivalently you could have computed the time window to be 2000 x 20 ns 40 us The delay would therefore have to be 10 us to get the trigger point to the 1 quarter of the time window Since nbrSamples 2000 and sampFrequency 5 0e 7 you would obtain delayNbrSamples 1500 Since the sampling frequency is known in this clock mode through the variable sampFrequency any read functions correctly return the value of the sampling interval In addition if the user supplied clock frequency inputFrequency is gt 800 MHz on DC271 FAMILY digitizers or in all cases for 10 bit and 12 bit digitizers the syste
83. lect an INPUT channel and set its level Name Set the level For COM IN You can also set the number of samples and the intervals used to compute the histogram Serial Number p Number of Channels p Use the vertical scrollbar to see how data arrays and data descriptors INPUT 1 are filled We added the read data in 132 Read Data Int32 vi to show you how to INPUT level Y 10 1 implement it Click the Read Int32 switch to activate the read process COM IN level v 10 Histogram 50 Num samples 100 gt intervals faio A mean value 1 i 1 1 1 1 0 00000 124 40n 124 43n 124 45mn 124 48n 124 50n 124 54 Time DataDesc Real64 Read Int32 dataPtr TDC Resolution ti t aan po Yi lo nbrsamples lo dataPtr sampleSize a fo 0 j nbrSamples sampleType lo 0 sampleSize oc i0 Int32 s DataDesc Int32 sampleType This VI demonstrates how to use a TC840 Time Counter It finds and initializes an instrument sets the basic parameters according to the controls on the front panel and then acquires and accumulates data as the user requests Note that the front panel controls should be set to their desired values before the VI is run Programmer s Guide Page 12 of 63 2 3 6 AqTx TC890 VI gt Acqiris Tx TCB90 vi Front Panel ce EK aa eee eae Kee tt t C S S oo A Resource Name PCI INSTRO Edit the resource name of the time counter module PCI
84. lly you also would start a new acquisition before readout but it is not required This is done automatically in the autoswitch mode as a consequence of the call to AcqrsD1_processData with a non zero flag value It can also be done with a call to AcqrsD1_configMode The read function returns zero into the dataDesc variables horPos tStampLo and tStampHi since they are unavailable in the context of a buffered waveform sequence With the function AcqrsD1_readData use this code fragment Programmer s Guide Page 42 of 63 AqReadParameters readParams Read Definitions AqDataDescriptor dataDesc Returned waveform values AqSegmentDescriptor segDesc Returned segment values long channel 1 nbrSamples 4000000 char waveformArray 4000000 readParams dataType ReadInt8 readParams readMode ReadModeStdw readParams nbrSegments 1 readParams firstSampleInSeg 0 readParams segmentOffset nbrSamples readParams firstSegment 0 Read first segment readParams nbrSamplesInSeg nbrSamples readParams flags 0 readParams reserved 0 readParams reserved2 0 0 readParams reserved3 0 0 memoryBank memoryBank 1 amp 0x1 switch to other bank AcqrsD1_configMode instrID 3 0 memoryBank AcqrsD1_acquire instrID essential AcgrsD1_readData instrID channel amp readParams waveformArray amp dataDesc amp segDesc The returned data array contains the acquired wavef
85. m correctly measures the value horPos and returns it with any waveform read function such as AcqrsD1_readData Thus the time position of the sampled data points can be known to within a small fraction of the sampling interval permitting very precise timing measurements as with the internal clock However the digitizer must be calibrated at the external clock frequency in use whenever inputFrequency or sampFrequency are changed Use this code We assume that a normal calibration has been done either during initialization or explicitly AcgrsD1_configExtClk Set to cont Ext Clk Make sure to apply the same external frequency as the value inputFrequency set in the function call above Acgrs calibrateEx instriD 2 0 0 The function Acqrs_calibrateEx with calType 2 readjusts some timing calibration constants but does not modify any vertical adjustment values such as gain or offset In first generation digitizers or when inputFrequency is lt 800 MHz in the second generation digitizers or AP AC SC analyzers in the digitizer mode the data read functions will return horPos 0 0 equivalent to a timing uncertainty of 0 5 samples For implementation reasons the acquired waveform in fact has a timing uncertainty that is twice as large i e 1 samples In this case the trigger timestamps of the sequence acquisition mode are not available Depending on the ratio of sampFrequency inputFre
86. ments 800 long startDelay 128 stopDelay 0 AcqrsD1_configMode instrID 7 0 0 AcqrsD1 _configAvgConfig instrID 0 NbrSamples amp nbrSamples AcqrsD1 _configAvgConfig instrID 0 NbrSegments amp nbrSegments AcqrsD1_ configAvgConfig instrID 0 StartDelay amp startDelay AcqrsD1_configAvgConfig instrID 0 StopDelay amp stopDelay Comments The value of the third and fourth argumenta to AcqrsD1_configMode must always be 0 When in AutoSwitch mode the following digitizer parameters are ignored e delayTime of the function AcqrsD1_configHorizontal is replaced by StartDelay and StopDelay e nbrSamples and nbrSegments of the function AcqrsD1_configMemory are replaced by NbrSamples and NbrSegments in the function AcqrsD1_configAvgConfig The values nbrSamples startDelay and stopDelay must be integer multiples of the block size which is always 16 in the AP240 AP235 Dual channel mode and 32 AP240 AP235 Single channel mode If the supplied value is not an integer multiple of the averaging block size it is truncated to the next lower integer multiple Thus nbrSamples 250 will be truncated to 240 15 16 for a Dual channel acquisition and to 224 7 32 for a Single channel acquisition You can query the actual value with the function AcqrsD1_getA vgConfig The value startDelay controls the time between the trigger and when the first digitized data sa
87. milar CompactPCI modules in order to make them appear as a single instrument with more channels After a number of digitizers have been combined with the functions AcqrsD1_multilnstrAutoDefine or AcqrsD1_multilnstrDefine for ASBus only each combined instrument can be controlled when using its instrumentID with the same functions as single digitizers We recommend the use of the automatic function unless you need special control over the order in which the digitizers are numbered within the MultiInstrument Please refer to the function AcqrsD1_multiInstrAutoDefine for details If you mix modules of the same model number with different memory lengths you must make sure that you never use more than the shortest memory length available Otherwise you will get invalid data on the short memory modules Under ASBus the automatic function always assigns the clock master role to a module with the shortest memory with the result that the function AcqrsD1_configMemory refuses to accept memory lengths beyond the shortest When configuring manually you might want to do the same Otherwise you need to explicitly check your requested memory lengths 3 17 1 Channel Numbering with ASBus In a Multilnstrument input channels are numbered from 1 to nbrChannels The number of channels can be retrieved with the function call Acgrs getNbrChannels instrID amp nbrChannels Channel 1 corresponds to channel 1 of module 0 Channel numbers increase first t
88. mon channel Channel number or Marker 0 for common or channel 0 1 6 for channel 1 6 7 denote the data is a Marker 27 0 Time Channel 0 The value plus one is the number of hit of the common channel Channel 1 to 6 The value is the time between the channel and the common Marker Value 0 Switch marker Switch from Auxiliary input A Value 1 Switch marker Common channel Event count Value 2 Switch marker Memory Full Value 16 Marker Auxiliary input B marker 3 12 Trigger Delay and Horizontal Waveform Position When using a digitizer the user has 3 instrument setup variables with which to position the acquired waveform in time e sampInterval the sampling interval inverse of the sampling frequency e nbrSamples the number of samples to acquire e delayTime the nominal trigger delay sampInterval Trigger delayTime nbrSamples Programmer s Guide Page 47 of 63 By convention the nominal trigger delay is taken relative to the beginning of the trace i e relative to the left edge of a real or virtual display grid It can be interpreted as the time from the trigger to the start of waveform recording If this number is positive recording starts after the trigger post trigger acquisition If it is negative recording starts before the trigger pre trigger acquisition In reality the acquisition always runs before any trigger occurs and delayTime controls the time between the trigger and the stopping of the acquisition
89. mple is stored It should also be noted that when startDelay is 0 the first few data points 5 in the case of Dual channel mode and 10 in the Single channel mode will always be 0 The stopDelay permits the addition of an extra delay to the dead time between the acquisition of subsequent waveforms Its minimum value may be zero Programmer s Guide Page 26 of 63 e Although not shown here a call to AcqrsD1_configControllO can be made in order to set a trigger veto time to be respected after the receipt of a Prepare for Trigger signal on a Control I O connector This feature is for AP101 AP201 analyzers only e Also not shown is a call to the function AcqrsD1_configAvgConfig to set a timeout value for the automatic completion of a segment in case the real trigger never arrives This feature is for AP101 AP201 analyzers only 3 5 2 Readout configuration There are two possible ways of reading the data when in the SSR mode user gates and threshold gates In all cases the entire acquisition must be read you cannot ask for fewer segments or points If you want to read all of the data you should define the appropriate gate These setting are also controlled through the AcqrsD1_configAvgConfig routine and therefore must be prepared before the acquisition is started They can be set independently for each channel if desired For user gate readout you have to define the groups of data samples that you want to read for each segment If needed new v
90. ms flags 0 readParams reserved 0 readParams reserved2 Ss Ss Ss 3 Ss Ss readParams nbrSamplesInSeg 2 nbrPeaks pos and neg peak a 3 B S S S ll So i sx a a readParams reserved3 AcgrsD1_readData instrID channel amp readParams waveformArray amp dataDesc NULL analyse and store data AcqrsD1_waitForEndOfAcquisition instrID timeout read original data if desired check on loop termination conditions and set finished The returned waveformArray contains exactly 2 nbrGates peaks each of which is described by 2 double precision floating point values The first pair of doubles contains the positive peak position within the gate in units of samples and the amplitude in codes The second pair of doubles contains the negative peak position and its amplitude The peak amplitude is a signed number in the range 128 0 127 0 with the two extreme values indicating underflow overflow conditions The peak position is normally positive Negative values are used for warnings In particular the value DBL_ MAX indicates that no peak was found The define of DBL_MAX can be found in the float h include file Each peak contains the following two words 0 63 Peak Position in samples from start of gate 0 63 Peak Amplitude in ADC units Use the following code to obtain the peak positions for the i th gate double positivePeakPos amp waveformArray 0 8 i double neg
91. o e de e o E A 30 3 9 1 Starting an Acquisition sennen ie 30 Programmer s Guide Page 3 of 63 3 9 2 Checkingif Ready for rigger ii dt RA in REA eee 30 3 9 3 Waiting for End of Acg isiioni ita eos 30 3 9 4 Stopping Forcing a D1 style Acquisition ceccesceeseesecesecesecscecseeeseeeseeseeeseesseenseensecaeeaecseessenseenaes 32 3 9 5 Analyzer and Peak P Autoswitch mode c ccscsscsssssssssessessesscssesseesessessessessessessesssesesseesesseesesseesesseeseeass 32 3 10 Di style Data Readout oi A A BAA en E ERR 34 3 10 1 Reading Digitizer Waveforms with the Universal Read Function cceccesesccescsseeeceseeeeeseeeereneees 35 3 10 2 Reading Sequences of Waveforms aniei E E AA EE ER AEEA 35 3 10 3 Averaging Waveforms in a Digitizer ooooconnccnnonoonnoonconnconnonnnonncon ccoo e e i E E rn nn nn nannnros 37 3 10 4 Reading an Averaged Waveform from an AVeraget sessssseeseresssresessrsresresetstestenessteressesresresersessrene 38 3 10 5 Reading a RT Add Subtract Averaged Waveform from an Averager seseseseeeesersersresereessreessseeees 39 3 10 6 Reading SSR Analyzer Waveforms esesesessseeseseeessseeeessesestsstesesstsesreseesteseesesststessestesteseesesseeesssesets 40 3 10 7 Reading Peak Analyzer Data and Histograms c ccccssssssesssssessessesseesesseesesseeseesscscssssessnssceseesveass 41 3 10 8 Reading AP101 AP201 Analyzer Waveforms c ceccceescessceseceeceseccecseeca
92. options PCI BUS0Z2 SLOTOG VI FALSE VI FALSE 7 amp instrumentID Again the bus and slot numbers must be contiguous to the keywords BUS and SLOT leading zeros are accepted Unfortunately it is not obvious at all by simple inspection which bus and slot number a given PCI device occupies One way to find out is to use AcqirisLive and to observe the bus slot numbers that can be found under the Help menu selection in Instrument Information Another way is to use the auto identification initialization method and then to interrogate each device with ViSession instrumentID char name 20 long serialNbr busNbr slotNbr Acqrs_getInstrumentData instrumentID name amp serialNbr amp busNbr amp SlotNbr Programmer s Guide Page 17 of 63 3 2 4 VXI Identification Instruments in IX20x VXI Carrier modules will also be found by the driver The resource name will be in the form VXI board logical_addr INSTR like VXTIO 1 INSTR 3 2 5 PXI VISA amp LabViewRT Identification The driver can also be used in the VISA environment In this case the resource name has the following allowed forms PXI lt bus gt lt device gt INSTR PXIO lt bus gt lt device gt INSTR PXI0 CHASSIS lt chassis gt SLOT lt slot gt INSTR 3 2 6 Firmware initialization AP FAMILY 12 bit FAMILY AC SC Time Counters In these modules the on board FPGA s field programmable gate arrays contain processor logi
93. or future operation The explicit acquisition processing readout sequence described above is shown in the following code AqReadParameters readParams Read Definitions AqDataDescriptor dataDesc Returned waveform values long channel 1 segmentNumber 0 long nbrPeaks 2 nbrGates nbrGates is defined by user long waveformArray 2 nbrPeaks long memoryBank 0 timeout 5000 timeout 5 seconds Insert whatever is required for Vertical and Trigger configuration AcqrsD1_configMode instrID 3 0 memoryBank AcqrsD1_acquire instrID Acquire into bank 0 AcqrsD1_waitForEndOfAcquisition instrID timeout At this point you should check the return value Programmer s Guide Page 45 of 63 bool finished false while finished memoryBank memoryBank 1 0x1 switch to other bank AcgrsD1_configMode instrID 3 0 memoryBank AcgqrsD1l_acquire instrID start new acquisition AcgqrsDl processData instrID 0 005 start processing AcqrsD1_waitForEndOfProcessing instrID timeout At this point you should check the return value readParams dataType ReadReal64 readMode ReadModePeak readParam readParams nbrSegments 1 readParams firstSamplelnSeg 0 readParams segmentOffset 0 readParams firstSegment 0 Read first segment readParams dataArraySize 2 sizeof double nbrPeaks readParams segDescArraySize 0 readPara
94. orms as a contiguous array E g if you configured nbrSamples 5000 the data points waveformArray 0 4999 correspond to the first waveform the data points waveformArray 5000 9999 correspond to the second waveform etc 3 10 8 2 Reading Gated Waveforms For reading gated waveforms the actual desired gates should be set with the setup function AcqrsD1_configSetupArray This function should be called before AcqrsD1_acquire is invoked to acquire any data that needs to be read using these gates To read back the gate values AcqrsD1_getSetupArray has to be used An example for the two routines is shown in the following code const int NbrGates 64 long channelNbr 0 long configObj AvgGate long lastGate NbrGates AgGateParameters gatePara NbrGates for int 1 0 i lt NbrGates i gatePara i GateLength 256 gatePara i GatePos i gatePara i GateLength AcqrsD1_configSetupArray instrID channelNbr configObj NbrGates gatePara The condition GateLength gt 4 is required Both GateLength and GatePos must be multiples of 4 You can read the gate parameters back with this code Programmer s Guide Page 43 of 63 const int NbrGates 64 long channelNbr 0 long configObj AvgGate long lastGate AgGateParameters gatePara NbrGates AcqrsD1_getSetupArray instrID channelNbr configObj NbrGates gatePara amp lastGate Make sure to use a pointer to the last argument since it re
95. oscope using the AqDx Digitizer Driver Not all the functionality of the Acqiris digitizers is supported in this program but most of the most commonly used functions are demonstrated in it Programmer s Guide Page 10 of 63 2 3 4 AqDx Accumulated Waveform Example VI gt AqDx Accumulated Waveform Example vi File Edit Operate Tools Browse Window Help aen Resouce Name Channel Horizontal Settings Vertical Settings its a PCI INSTRO yl Number of Samples Full Scale gt ae 4 1000 45 000 Trigger Source Trigger Coupling Sampling Interval Offset Finternal bc an 0 000 TrigLevel1 TrigLevel2 Trigger Slope Delay Time Coupling Spoo p o Positive So ce 0 c 1 MOhm TUE Qe Accumulated Waveform Press to Accumulate another waveform Ji Number of Accumulations IY vy 4 1 5 7 This VI demonstrates how to use the Accumulate Waveform function of the Acqiris Digitizer Driver It finds and initializes a digitizer sets the basic parameters according to the controls on the front panel and then acquires and accumulates waveforms as the user requests Note that the front panel controls should be set to their desired values before the VI is run Programmer s Guide Page 11 of 63 2 3 5 AqTx TC890 VI b Acqiris Tx 1CB40 vi Front Panel Eile Edit Yiew Project Operate Tools Window Help oN Resource Name PCI INSTRO PCI INSTRO Edit the resource name of the time counter module Se
96. particularly important for persistence displays or highly zoomed random interleaved displays as generated from overlaid segments where a single waveform or waveform segment contributes only a few data points to the display Acqiris digitizers feature a Trigger Time Interpolator TTI which measures the time between the trigger event and the next sampling clock to a fraction of the sampling interval It permits very precise positioning of the acquired trace in highly zoomed displays particularly when multiple acquisitions of the same signal are used In many other applications this value can be ignored The following drawing completes the description of a real life waveform yer Origin sampInterval First data point e Trigger hOffset delayTime nbrSamples Programmer s Guide Page 48 of 63 e The value of delayTime positions exactly the left edge of the display or the exact nominal beginning of the waveform with respect to the stable trigger time which is the real reference point We define the time trigger time delayTime as the time origin for the waveform which is equivalent to saying that the trigger always occurs exactly at the time delayTime e The first data point of the waveform is defined as the last acquired data point before the time origin It is indexed with i 0 in the formula below A NOTE It is important to realize that if a single segment is read e g with AcqrsD1_readData the
97. quency a waveform is sampled either on negative going transitions of the external clock signal through the user defined threshold or when the ratio is gt 1 on both of the transitions Programmer s Guide Page 52 of 63 NOTE First generation digitizers that have more than one converter channel DC240 DP210 and DP211 will generate two data samples for each sampling interval You must dimension your acquisition and readout for twice the normal amout of data and can then either drop every other data sample from the record or average the two data values which could enhance the signal to noise ratio 3 16 3 External Clock Start Stop The start stop external clock mode clockType 4 permits the application of a variable external clock It should not be used for the DP1400 10 bit or 12 bit digitizers The clock can be setup to give bursts during which the frequency is between 10 MHz and 500 MHz The first sample of each burst may have to be ignored The waveform is sampled on positive going transitions of the external clock signal through the user defined threshold Thus the sampling rate is equal to the input frequency For digitizers and Averagers Analyzers in the digitzer mode there is no concept of trigger when a Start Stop clock is used Therefore all trigger parameters will be ignored This also means that there is no concept of sequence acquisition Operation in a channel combined mode is not possible The AC SC Analyzers can
98. rPoints bckGndWform nbrReturnedSamples amp horPos sampTime amp timeStampLo amp timeStampHi The examples above assume that the background and the averaged waveforms are read in Volts In this case the background data points are simply subtracted from the averaged waveform However if you read the background and the averaged waveforms as 32 bit sums with the function long bckGndWform nbrPoints Background as 32 bit sum AcqrsD1_readData instrID channel amp readParams waveformArray amp wfDesc amp segDesc you must correct the average as follows corrWform i waveformArray i bckGndWform i 128 nbrAvgWforms The last term corrects for the fact that the 32 bit data are unipolar and that for display purposes the corrected waveform should be in the middle of the vertical range if the averaged waveform is the same as the background 3 4 4 Configuring Noise Suppressed Accumulation NSA As discussed in the User Manual Family of Averagers the module can be configured to only accept data above a fixed threshold and if desired to shift the data in that case Since these two values are expressed in Volts and used as ADC counts they have to be converted before use The User Manual describes this transformation that depends on whether Data Inversion has been enabled The NSA threshold functionality must be enabled and a threshold defined If this has been done the NSA base subtraction can also be enabled and will
99. rage requirements When using the routine AcqrsD1_readData you must allocate waveform storage and inform the driver about the number of bytes available Raw data readout requires exactly the number of bytes corresponding to the number of segments times the number of data points per segment User gate readout for each segment requires 8 bytes for the time stamp and an overhead of 8 bytes for each gate This must be added to the total number of samples in all of the gates to get the required length for each segment and multiplied by the number of segments to get the waveform array length Programmer s Guide Page 40 of 63 For threshold gate readout the program should allocate the space needed for the worst case This means 8 bytes for the time stamp 8 bytes for a gate block header and space for the total number of samples segment This must be multiplied by the number of segments to get the waveform array length It should be noted that the FPGA will generate a single gate block if there are less than 32 data points below threshold between two desired data points 3 10 7 Reading Peak Analyzer Data and Histograms 3 10 7 1 Reading the gated data The gated data of the current event can be read out as described in 3 10 6 3 Gated data This is the only output format that gives access to the segment time stamps 3 10 7 2 Reading the data in the peak regions The data of the peak regions in the current event can be read out using readMode 10
100. ransferring single records of 100 000 samples recorded at 2 GS s M 1 N 100000 Xfr 0 01 Cpy 0 00625 Ovhd pu 62 5 Ovhd yg 3 125 Extra 480 192 672 T M Ovhd yy M N Xfr 62 5 1000 1063s T Ovhd pu M OVA p M N Extra Xfr M N Cpy 62 5 3 125 100672 0 01 100000 0 00625 1698 us It is therefore more favorable to use the function AcqrsD1_readData for readMode 0 Transferring 100 segments of 1000 samples recorded at 2 GS s M 100 N 1000 Xfr 0 01 Cpy 0 00625 Ovhd py 62 5 Ovhd yg 3 125 Extra 480 192 672 T M Ovhd yy M N Xfr 100 62 5 100 1000 0 01 7250 us T Ovhd pu M Ovhd y M N Extra Xfr M N Cpy 62 5 100 3 125 100 1672 0 01 100 1000 0 00625 2672 us The function AcqrsD1_readData for readMode 1 ReadModeSeqW is about 2 7 times faster Programmer s Guide Page 61 of 63 B DC270 connected to a 500 MHz Pentium with a MXI 3 interface Transferring single records of 100 000 samples recorded at 100 MS s M 1 N 100000 Xfr 0 012 Ovhd py 100 Ovhd T Ovhd pu M Ovhd 100 5 100120 0 012 100000 0 01 2306 us buffer buffer Cpy 0 01 5 Extra 240 10 96 120 T M Ovhd yy M N Xfr 100 1200 130045 M N Extra Xfr M N Cpy It is therefore more favorable to use the function AcqrsD1_readData for readMode 0 Transferring 1000 segments of 500 samples
101. rmance reasons Its size must be at least the requested number of samples nbrSamples 32 for reasons of data alignment The content of this working array is not meant to be used by the client Please note that in both cases sub sample timing information i e horPos see section 3 13 Horizontal Parameters in Acquired Waveforms is not taken into account 3 10 4 Reading an Averaged Waveform from an Averager Averaged waveforms can be read out either in Volts or as 32 bit accumulated sums In either case we recommend the use of the general purpose read function AcqrsD1_readData rather than the obsolete function AcqrsD1_readRealWform 3 10 4 1 Averaged Waveforms in Volts You should use the general purpose function AcqrsD1_readData As long as the mode is still set to averager either function automatically divides the accumulated waveform sum by the number of acquired waveforms and returns the result in Volts They also return zero into the variables horPos tStampLo and tStampHi since they are irrelevant in the context of an averaged waveform Use this code fragment for the general purpose function AqReadParameters readParams Read Definitions AqDataDescriptor wfDesc Returned common waveform values AqSegmentDescriptorAvg segDesc Returned segment values long channel 1 nbrSamples 20000 double waveformArray 20000 readParams dataType ReadReal64 Request Volts readParams readMode ReadModeAvgw readP
102. rms the formula above yields wrong results As a check that the correct value of nbrWforms was used the value of sum i before conversion to an integer must already be very close to an integer Use this code fragment for the legacy function long channel 1 segmentNumber 0 nbrSamples 20000 long returnedSamples tStampLo tStampHi double waveformArray 20000 horPos sampTime AcgrsD1_readRealWform instrID channel segmentNumber 0 nbrSamples waveformArray amp returnedSamples amp horPos sampTime amp tStampLo amp tStampHi 3 10 4 2 Averaged Waveforms as 32 bit Sums You must use the general purpose function AcqrsD1_readData Use this code fragment AqReadParameters readParams Read Definitions AqDataDescriptor wfDesc Returned common waveform values AqSegmentDescriptorAvg segDesc Returned segment values long channel 1 nbrSamples 20000 long waveformArray 20000 readParams dataType ReadInt32 Request 32 bit sums readParams readMode ReadModeAvgw readParams nbrSegments 1 readParams firstSamplelnSeg 0 readParams segmentOffset nbrSamples readParams firstSegment 0 Read first segment readParams nbrSamplesInSeg nbrSamples readParams dataArraySize sizeof waveformArray readParams segDescArraySize sizeof segDesc readParams flags 0 readParams reserved 0 readParams reserved2 0 0 readParams reserved3 0 0 A
103. rocedure is also shown in the GetStarted cpp VxWorks sample program Thus Acqrs_InitWithOptions has to be called with ViString options cal 0 status Acgrs InitWithOptions resourceName VI_FALSE VI_FALSE options amp instrumentID i Then before using the desired module in any mode you should execute code like that shown below ViString FPGADirectoryName C firmware or C for ETS Acgrs configlogicDevice instrumentID NULL FPGADirectoryName 2 As a final step you should now calibrate the instrument which will cause the FPGA files to be loaded Status Acgrs calibrate instrumentID 3 2 7 Automatic Definition of MultiInstruments The function AcqrsD1_multiInstrumentAutoDefine automatically searches for all sets of modules that are connected with ASBus and configures each such block as a single MultiInstrument It then reports the total number Programmer s Guide Page 18 of 63 of instruments found including individual modules without ASBus connections You still need to retrieve the instrumentID for each instrument by calling the function Acqrs_InitWithOptions afterwards as shown below ViSession instrumentID 10 long nbriInstruments ViStatus status vistring options Tr status AcgrsD1 multilnstrAutoDefine amp nbrinstruments Retrieve the instrument identifiers for long 2 Us 1 lt nbrinstriments 1 char resourceName 20 sprintf resourceName PCI INSTR
104. rollO with the parameters connector 1 I O A or 2 I O B and signal 9 Note that when this mode is in use the Enable trigger input signal 6 functionality of AcqrsD1_configControlIO cannot be used The function AcqrsD1_configFCounter sets the parameters specific to the frequency measurements AcgqrsD1 configFCounter instrID channel type targetValue apertureTime 0 0 UY Comments e Channel numbers run from 1 to the available number of signal channels in the digitizer e The value type is 0 for Frequency 1 for Period 2 for Totalize by Time and 3 for Totalize by Gate e The targetValue is an estimator of the expected result If no estimate is possible use the value 0 0 This value is only used to activate the HF trigger mode which extends the useable frequency range By default the frequency range is extended except type Measurement Divide by 1 0 Frequency if targetValue is smaller than 1 kHz 1000 0 and larger than 0 0 1 Period if targetValue is larger than 1ms 0 001 2 Totalize by Time always the HF mode is never used 3 Totalize by Gate always the HF mode is never used e The apertureTime defines the minimum time for a frequency measurement it may be longer if the frequency is very low In the Totalize by Time mode the value of apertureTime determines the time window during which the input pulses are counted The frequency counter mode is set with the function AcqrsD1_configMode with mode 6 After confi
105. ronously to the sampling clock and thus will fall randomly anywhere within a sampling interval When averaging waveforms this will result in an effective bandwidth reduction since the waveforms are randomly shifted with respect to each other by up to Y sampling interval In Start on Trigger mode the trigger occurs before recording starts It still occurs asynchronously with respect to the internal VCO which is always running However if the requested sampling rate is less than the VCO frequency e g 100 MS s while the clock runs at 500 MHz then the time correlation between the trigger and the effective sampling clock is within VCO time interval not Y sampling interval Therefore when averaging the bandwidth reduction will be less than in the normal mode The value delayTime in the function AcqrsD1_configHorizontal is ignored As usual the digitizer requires some memory overhead for additional samples The function AcqrsD1_bestNominalSamples returns the maximum number of available samples Use this code to use the Start on Trigger mode AcgrsD1_configXXX configure other parameters AcqrsD1 configMode instrID 0 0 1 AcgrsDl_acquiretinstriD AcqrsD1_waitForEndOfAcquisition instrID timeout Read out data etc before calling again AcqrsDl_ acquire Note that the function AcqrsD1_acquire is still needed However it behaves somewhat differently in that is does not start data re
106. rs sampInterval and delayTime as defined by AcqrsD1_configHorizontal are ignored You need to give the driver the current input frequency and the requested sampling frequency with the variables inputFrequency and sampFrequency of the function AcqrsD1_configExtClock The input frequency inputFrequency must be between 10 MHz and 500 MHz in the first generation models while it must be between 20 MHz and 2000 MHz for the second generation DC271 FAMILY or AP240 AP235 signal analysis platforms or for the 12 bit FAMILY between 100 MHz and the value for the maximum allowed sampling frequency Note that for normal operation of the 12 bit FAMILY digitizers the sFmax for each converter should be kept above 50 MHz The acceptable values for sampFrequency are dividers sFmax n of the maximum allowed sampling frequency sFmax where n 1 2 4 8 20 40 80 200 The sFmax depends on the model and on the number of combined channels nbrConvertersPerChannel of AcqrsD1_configChannelCombination Model Input sFmax vs nbrConvertersPerChannel Frequency range MHz 1 2 4 DC122 100 2000 2 x inputFrequency DC135 20 2000 x inputFrequency x inputFrequency DC140 20 2000 1 x inputFrequency 1 x inputFrequency DC152 100 2000 1 x inputFrequency 2 x inputFrequency DC211 DC211A 20 2000 2 x inputFrequency DC222 100 2000 4 x inputFrequency DC241 DC241A 20 2000 1 x inputFrequency 2 x inputFrequency DC252 100 2000 2xinputFrequency 4 x inputFrequency DC271
107. rt the acquisition One such command is required for each module in use However if several digitizers are combined to a single Multilnstrument with ASBus only a single command is needed for the combined instrument 3 9 2 Checking if Ready for Trigger If many modules are being used it may be useful to know when they are all ready to accept a trigger This can be done by verifying that they are all finished with their pre trigger phase PreTrigger 0 by using the call below to all instruments or the last instrument started Acgqrs getInstrumentInio instrib lsPrelTriggerRunning amp Pretrigger 3 9 3 Waiting for End of Acquisition Usually data cannot be read from the instrument until the acquisition is terminated The application may wait for an acquisition to end either by polling or by waiting for interrupt A Simple Polling use the following code fragment for polling the interrupt status Programmer s Guide Page 30 of 63 ViBoolean done 0 long timeoutCounter 100000 while done amp amp timeoutCounter gt 0 AcgrsD1_acgDone instrID amp done poll for status or AcqrsT3_acqDone instrID amp done the Time Counter equivalent if timeoutCounter lt 0 timeout stop acquisition STOP ACQUISITION NOTE The code above has the disadvantage of wasting CPU time while checking the instrument status during the entire acquisition period In addition the timeout counter value should be set accor
108. ry lt AcqirisDxRoot gt MATLAB To use it either set the MATLAB current directory cd Command to lt AcqirisDxRoot gt MATLAB or the file from that directory to the directory of your choice GetStarted Filename Aq_GetStarted m Argument No Argument This first example shows you how to perform a single acquisition The desired configuration is loaded You then start the acquisition and read and plot the acquired data 2 6 Wind River VxWorks Tornado The VxWorks sample program is written for the Tornado environment The GetStartedVxW cpp file contains a simple user program which e spawns a process with a large stack as needed by the Acqiris driver e finds the Acqiris digitizers on the target machine e initializes the first or only one Programmer s Guide Page 14 of 63 e configures some acquisition parameters and rereads them for checking e loops 100 times over a cycle that starts the acquisition waits for it to terminate reads the waveform 2 6 1 Compiling This file can be compiled as is within the GetStarted VxW wsp Tornado workspace However please make sure to run an update to the project dependencies You may need to change the directory paths for the Tornado include files and the Acqiris include files if you move the Tornado directory or use a different development environment In the latter case you must verify that the compilation flags D_VXWORKS D_ACQIRIS are present 2 6 2 Loading F
109. s fe Project Acqiris Tx lvproj E My Computer 9 Examples Lg Acqiris Tx TC840 vi eo Acqiris Tx lib E E Public ii GS Action Status ce 3 Configure d E Data teh Utility ES E dir mnu ioa VI Tree vi i ie EY Private i Acqiris Tx Readme html p ES Dependencies je Build Specifications The Example folder contains ready to use potential starting points for your own programs Individual library functions can be found at the Public level or in one of the 4 categories shown Query functions are in the Utility folder The block diagram of the VI Tree vi can be used to access individual functions It allows quick and easy access to all needed vi s The AqBx Generic functions family contains the following vi s Initialize Configuration Utility The AqBx Examples section contains three very simple cases to show some basic functionality Programmer s Guide Page 8 of 63 The AqDx Digitizer functions family contains the following vi s The diagram also shows the AqBx functions that can be used These AqBx functions are to be preferred over their AqDx equivalents Getting Started Application Example Initialize E ES Configuration Status Action Data Utility The AqTx Time Counter functions family contains the following vi s The diagram also shows the AqBx functions that need to be used Examples Initialize Configuration Status Action Data Ut
110. s tStampLo Else Programmer s Guide Page 49 of 63 gt e xStampLo tStampLo End If timeStamp CDec tStampHi Two32 xStampLo timeDiff timeStamp previousStamp Arithmetic operations between such decimal variants can be done as with other integer variables The manipulation of tStampLo is somewhat complicated because this variable is a signed 32 bit integer but must be added as an unsigned integer to the shifted tStampHi e In LabVIEW convert the timestamp to an extended floating point number and do arithmetic operations as with other variables e In LabWindows CVI the easiest way to manipulate timestamps is to convert them first to doubles ViReal64 dlow dhigh tstamp dlow ViReal64 low dhigh ViReal64 high tsamp dlow 4294967296 0 dhigh 3 16 External Clock and Reference The external reference mode replaces the internal 10 MHz reference clock with an external one at the same or a similar frequency from which the actual sampling clock is derived In the external clock mode a waveform is sampled according to a clock derived from transitions of the external clock signal through the user defined threshold We distinguish between continuous external clock operation and start stop external clock operation All external clock reference modes are configured with the function AcqrsD1_configExtClock The external clock reference signal should have a peak peak amplitude of at least e 0 5 V for t
111. s are still contained in one library called AqDrv4 The LabView interface is split into the three corresponding AqXX parts The AcqrsD1 section includes redundant copies of the generic functions so that backward calling compatibility can be maintained for existing code Preliminary remark it is assumed in the following that the hardware and Acqiris software installations see User Manual chapter 2 have already been completed NOTE Visual C C VxWorks and LabWindows CVI all rely on the standard VISA types defined by VXI plug amp play Systems Alliance VISA The visatype h include file can be found in the include directory created at installation 2 1 Visual C For digitizer users e Open either the project file GetStartedVC dsp or GetStartedAvgVC dsp in VisualC and build the project e Note that you should insert the lines include AcqirisImport h include AcqirisDlImport h at the beginning of every file that will access Acqiris D1 Driver functions e The project should link to the AqDrv4 lib file For time counter users e Open either the project file GetStartedTC840 dsp or GetStartedTC890 dsp in VisualC and build the project e Note that you should insert the lines tinclude AcqirisImport h tinclude AcqirisT3Import h at the beginning of every file that will access Acqiris Time Counter Driver functions e The project should link to the AqDrv4 lib file 2 2 LabWindows CVI e Open the project file GetStarted prj in Lab
112. strID channel amp readPar amp adcArray amp dataDesc amp segDesc To keep the same interface for the AP240 as was the case for the AP101 AP201 the processing step is kept but the dummy processing value is used Actually the software knows which processing is needed from the setup values sent to AcqrsD1_configAvgConfig Thus the software must wait for the end of processing even if the processing mode is set to NO PROCESSING 3 9 5 2 What happens when the AutoSwitch semaphore is not set After the processing of an acquisition if the semaphore is not set the FPGA waits for further instructions This feature ensures that the software has finished with the old buffer and gives full compatibility with older software implementations If you make a call to AcqrsD1_stopAcquisition you shouldn t try to read the last acquisition s data 3 9 5 3 Changing acquisition settings while acquiring and reading events If you want to change any of the acquisition settings you must o terminate the current acquisition sequence AcqrsDl1 _processData instrID processType 2 do a bank switch but do not start status AcgrsD1 waitForEndOfProcessing instrID timeout usual wait finish reading the data associated with the old settings AcgrsD1_readData instrID channel amp readParams waveformArray amp wfDesc amp segDesc o configure the instrument for the new values and start the new set of acquisitions go back
113. t the physical ordering of the modules This information is stored in a file named AqGeo map which the driver will load when an ASBus instrument is defined The driver will search for the AqGeo map file as follows e First the file will be searched for in the working directory of the application e Then the working directory will be searched for a file AqDrv4 ini e Finally the directory pointed to by the environment variable AcqirisDxDir will be searched for a file AqDrv4 ini e The AqDrv4 ini file should contain the name of a directory which will also be searched for the AqGeo map file Here is a typical example of its contents Acgiris GeoMapPath C Program Files Acqiris bin Programmer s Guide Page 20 of 63 3 2 10 Simulated Devices If you want to work with simulated devices none of the methods above are applicable Any module supported by the driver can be simulated analyzers and averagers generate data in digitizer mode Any memory option available for the module can be used for a call to Acqrs_setSimulationOptions as shown in this code fragment ViSession instrumentID ViStatus status status Acgrs setSimulationOptions M2M Initialize the instrument status Acgrs_ InitWithOptions PCI DC110 VI FALSE VI_FALSE simulate TRUE amp instrumentID The first function call sets the instrument options that you want to obtain e g M2M for the long memory option of a DC110 In th
114. tisfy that condition 3 10 8 3 Data Processing before Readout In buffered mode the AP101 offers the capability of processing the acquired data before readout This operation must be explicitly requested by the application after the data acquisition has terminated Depending on the processing algorithms used you may have to prepare the data processing by setting the appropriate parameters with the function AcqrsD1_configSetupArray In the peak detect mode the AP101 will return for each gate exactly 2 peaks first the positive and then the negative one some of which might be marked as invalid if no valid peak exists Thus you should define the gates in the same way as described in the previous section A typical acquisition processing readout sequence in autoswitch buffered mode would be 1 Configure the APXXX for appropriate channel timebase trigger and gate parameters 2 Start the first acquisition Programmer s Guide Page 44 of 63 3 Give the order to switch banks and start the next acquisition and data processing on the current acquisition as soon as possible The processing can overlap with the data acquisition since it automatically deals with the memory bank that is not selected for acquisition If you need to read the original data choose the no processing option 4 Wait for the processing to be terminated read the processed result Note that the processing will not destroy the originally acquired data
115. titute for any form of established process or equipment used to monitor or safeguard human health and safety in medical treatment WARNING The modules discussed in this manual have not been designed for making direct measurements on the human body Users who connect an Acqiris module to a human body do so at their own risk 1 5 Warranty Please refer to the appropriate User Manual 1 6 Warranty and Repair Return Procedure Assistance and Support Please refer to the appropriate User Manual 1 7 System Requirements Please refer to the appropriate User Manual Programmer s Guide Page 6 of 63 2 Programming Environments amp Getting Started Agilent Technologies supplies sample programs as a starting point for the development of user specific Acqiris applications For Windows systems there are samples for the Visual C C Visual Basic LabWindows CVI LabVIEW and MATLAB For VxWorks real time systems there are sample programs for Tornado An Application Program Interface API hlp file with a shortcut named Acqiris Instrument Driver Help is available and contains condensed descriptions of all of the interface functions The API has been split into three families Acqrs Generic functions AqBx these can be used for all Acqiris Instruments AcqrsD1 Digitizer functions AqDx to be used for Digitizers and Analyzers AcqrsT3 Time Counter functions AqTx to be used for the family of Time Counters All of these function
116. tor are returned These structures are defined in the header file AcqirisDataTypes h The following parameter setting can be used for reading a single waveform segment in 8 bit representation static long nbrSegments 1 readMode 0 requires this value const long nbrPoints 1000 char dataArray nbrPoints 32 AqReadParameters readPar new AqReadParameters AqDataDescriptor dataDesc new AqDataDescriptor AqSegmentDescriptor segDesc new AqSegmentDescriptor nbrSegments readPar gt dataType 0 0 byte readPar gt readMode 0 0 standard waveform readPar gt nbrSegments nbrSegments readPar gt firstSampleInSeg 0 readPar gt segmentOffset 0 unused parameter readPar gt firstSegment 0 readPar gt nbrSamplesInSeg nbrPoints readPar gt dataArraySize sizeof dataArray readPar gt segDescArraySize sizeof AqSegmentDescriptor nbrSegments readPar gt flags 0 readPar gt reserved 0 readPar gt reserved2 0 0 readPar gt reserved3 status AcgrsDl readData instrID channel readPar dataArray dataDesc segDesc Comments e The segment numbers run from 0 to nbrSegments 1 e The value of segDesc gt horPos is the time interval in seconds between the first data point and the nominal time origin of the trigger delay It is always in the range sampTime 0 It is useful for a very precise positioning to a fraction of the sampling interval of the waveform
117. trID AcqrsD1_configAvgConfig instrID Cf 2E long tdcOverlay 0 AcqrsD1_configAvgConfig instrID Programmer s Guide 0 TdcHistogramDepth stdcDepth 0 TdcHistogramIncrement amp tdcIncr 0 TdcProcessType amp tdcType the acquisition has segments to be histogrammed independently 0 TdcOverlaySegments tdcOverlay Page 28 of 63 3 7 Configuring AP101 AP201 Analyzers The models AP101 AP201 have 2 operational modes normal and buffered also called dual memory controlled with the function AcgrsD1_configMode instrID mode 0 flags The value mode can be set to 0 normal or 3 dual memory In mode 3 the parameter flags sets the memory bank into which to acquire 0 or 1 The buffered mode uses a number of additional configuration parameters that describe the requested buffered acquisition conditions Use the following short code fragment to configure a buffered acquisition sequence of 800 waveforms of 5000 data points with a start delay of 128 samples into memory bank 1 Configure long nbrSamples 5000 nbrSegments 800 long startDelay 128 stopDelay 0 AcqrsD1_configMode instrID 3 0 1 AcqrsD1_configAvgConfig instrID 0 NbrSamples amp nbrSamples AcqrsD1_configAvgConfig instrID 0 NbrSegments amp nbrSegments AcqrsD1_configAvgConfig instrID 0 StartDelay amp startDelay AcqrsD1_configAvgConfig instrID 0 StopDelay
118. turns the number of gates lastGate cannot exceed the number of gates being written To read the gated waveforms use the function AcqrsD1_readData AqReadParameters readParams Read Definitions AqDataDescriptor dataDesc Returned waveform values AqSegmentDescriptor segDesc Returned segment values long channel 1 nbrSamples 20000 char waveformArray 20000 readParams dataType ReadInt8 readParams readMode ReadModeGateW readParams nbrSegments 1 readParams firstSamplelnSeg 0 readParams segmentOffset nbrSamples readParams firstSegment 0 Read first segment readParams nbrSamplesInSeg nbrSamples readParams flags 0 readParams reserved 0 readParams reserved2 0 0 readParams reserved3 0 0 AcgrsD1_readData instrID channel amp readParams waveformArray amp dataDesc amp segDesc The returned data array contains the acquired waveforms as a contiguous array of dataDesc gt returnedSamples bytes Note Make sure that the waveformArray is large enough to hold the sum of all GateLength s times the nbrSegments As a rule the waveformArray has to have as a minimum size the sum of all the gate sizes times nbrSegments waveformArray gt 3 GateLength nbrSegments Note If for each gate the sum GatePos GateLength exceeds the nbrSamplesInSeg GatePos is reduced to satisfy GatePos GateLength lt nbrSamplesInSeg If this is not sufficient GateLength is shortened to sa
119. ue for the automatic completion of a segment in case the real trigger never arrives 3 8 Configuring TC8xx Time Counters Use the following short code fragment for a device configuration Configure long i chan slope 0 double trigLevel 0 2 double timout 0 1 Acqrs_getNbrChannels instrumentID amp n_chan for i 0 i lt n_chan i AcqrsT3 contigChannel instrumentID itl slope triglevel 0 AcgrsT3 configChannel anstrumentip 1 trigSlope triglevel 0 AcgrsT3 configAcgConditions instrumentID timeout 0 0 Programmer s Guide Page 29 of 63 Comments e Channel numbers run from 1 to nbrChannels not from 0 The common channel uses the number 1 e The configuration functions are protected against illegal or incoherent values Thus the system might adapt the values you ask for The query counterpart of this function AcqrsT3_getChannel can be interrogated to learn what the driver did to the values e The granularity of a threshold value setting is limited by the hardware that uses a 12 bit DAC covering the desired range e The timeout for the acquisition must be chosen to allow the maximum reasonable value 3 9 Data Acquisition Instrument operation is preceded by configuring the instrument parameters and then starting the acquisition sequence New settings are only loaded into the module when the acquisition is started there is one exception to this rule as discussed for analyzer user
120. uide Page 23 of 63 e The ditherRange value may be between 0 no dithering and 15 max dithering Please refer to the next section for further explanations 3 4 2 Dithering Dithering reduces the effect of non ideal differential non linearity of the analog to digital converter by adding or subtracting small offsets to the input signal The offset is constant during the acquisition of a single waveform and then modified to another value during the next waveform The dithering range N is programmable between 0 no dithering and 15 with the function AcqrsD1_configAvgConfig instrID channelNbr DitherRange N Dithering reduces the range of the ADC by N levels at the top and another N levels at the bottom In order to avoid any undesirable effects you should make sure that the signal range of interest is within the reduced ADC range 3 4 3 Fixed Pattern Background Subtraction If an averaging operation is executed while the input is open or no signal is applied the averaged waveform should tend to a constant value with a standard deviation Oag O VN where N is the number of waveforms in the average and o is the standard deviation of a single waveform In reality only random noise sources are averaged out while those that are coherent with the sampling clock are not reduced The open input averaged waveform thus represents the fixed pattern background of the averager Subtracting this waveform from each subsequently

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