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Digitizers User Manual

1. Models DC271 FAMILY 12 bit FAMILY Traditional API equivalent AcqrsD1_ configControllI0O id 1 AcqrsD1_ getControllO id 1 Discussion Studying the current range of the attribute may be needed to understand all of the possible values ctrILOBSignal Purpose Control the functionality of the CtrlI O B connector Prefixes Access Type Values RW string Models DC271 FAMILY 12 bit FAMILY Traditional API equivalent AcqrsD1_ configControllIO id 2 AcqrsD1_ getControllIO id 2 Discussion Studying the current range of the attribute may be needed to understand all of the possible values Programmer s Guide Page 82 of 100 acqiris ctrITOPxiRefl10MHz Purpose Control the use of the PXI Reference clock Prefixes Access Type Values RW string TOEP TOn Models DC135 DC140 DC211 DC211A DC241 DC241A DC271 DC271A Traditional API equivalent AcqrsD1_ configControllO id 11 AcqrsD1_ getControllIO id 11 Discussion The value On will set the instrument to use the PXI 10 MHz reference as the internal clock reference ctrITOPxiStar Purpose Control the use of the PXI Star trigger Prefixes Access Type Values RW string MOLE Trig in TrigOut Models DC135 DC140 DC211 DC211A DC241 DC241A DC271 DC271A Traditional API equivalent AcqrsD1_ configControllO id
2. AcqrsD1_readData instrumentID 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 1 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 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 waveforms 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 AcqrsD1_readRealWform inst
3. 19 881E 324 Acquired Waveform limited to 10 segments reserved2 10 000E 0 reserved3 10 000E 0 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 2 Example Scope VI AqDx Example Scope vi File Edit Operate Tools Browse Window Help Digitizers Horizontal Settings Vertical Settings error out Channel Es a Number of Segment Full Scale a c 25 000 Trigger Settings rid y Number of Samples Offset PCI sINSTR1 Trig Source Trig Channel Trig Slope ESET E El Finternal if Positive eoo 30 000 TrigLevel1 TrigLevel2 Trig Coupling ame Interval prea SS 0 000 0 000 25082 ADC 1 MOhm UE Delay Time Bandwidth p oo 0 Sfo bandwidth limit 7 Cad fsa 0 4 1 1 1 1 1 1 1 1 1 1 1 0 0E 0 2 0E 7 4 0E 7 6 0E 7 f 1 0E 6 1 2E 6 1 4E 6 1 6E 6 1 8E 6 2 0E 6 ENR This VI presents a basic interactive virtual oscilloscope 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
4. Since each channel is controlled by its own FPGA the 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 status AcqrsDl_ configAvgConfig InstrumentID 0 channel Picentrol 6TSResest 3 6 Configuring AP101 AP201 Analyzers The models AP101 AP201 have 2 operational modes normal and buffered also called dual memory controlled with the function Programmer s Guide Page 29 of 100 acqiris AcgrsD1 conftigMode instrumentID 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 AeqrsDl coenfigMode instrumentID 3 0 1 AcqrsD1_configAvgConfig instrumentID 0
5. 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 3 8 6 Reading SSR Analyzer Waveforms 3 8 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 ADC value at position i unipolar i e 0 or positive volts 1 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 cannot ask for a reduced number of segments Programmer s Guide Page 39 of 100 acqiris 3 8 6 2 Raw data The complete data can be read out using readMode ReadModeStdW 0 This mode can be used to read the entire acquisition which may have many segments You cannot ask for a partial range of the data Segment timestamps are not available for raw data readout 3 8 6 3 Gated
6. acqiris Acqiris GeoMapPath C Program Files Acqiris bin 3 2 8 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 in its digitizer mode Any memory option available for the module can be used for a call to AcqrsD1_setSimulationOptions as shown in this code fragment ViSession instrumentID ViStatus status status AcqrsD1l_ setSimulationOptions M2M Initialize the digitizer status AcqrsDl 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 the 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 digitizer module name The simulation options will apply to all subsequent calls to AcqrsD1_InitWithOptions until they are reset with AcqrsD1_setSimulationOptions 3 2 9 Terminating an Application For an orderly shut down of your application we recommend the following sequence Stop the digitizers for long i 0 i lt nbrInstruments itt status AcgqrsDl stopAcquisition instrumentID iy AcgrsD1l closeAll Stopping the acquisition of all d
7. acqiris 1 Introduction 1 1 Message to the User Congratulations on having purchased an Acqiris data conversion product Acqiris Digitizers 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 Programmer s 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 operation of a personal computer PC running a Windows 95 98 2000 NT4 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 or a digital oscilloscope 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 produc
8. 32 for a Single channel acquisition You can query the actual value with the function AcqrsD1_getAvgConfig e The value startDelay controls the time between the trigger and when the first digitized data sample 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 e 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 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 three possible ways of reading the data when in the SSR mode raw data user gates and threshold gates In all three cases the entire acquisition must be read you cannot ask for fewer segments or points 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
9. Control the slope or type of the transition to be used for the trigger Prefixes Access Type Values channel amp ext RW string Pos Neg WindowIn WindowOut HFDiv4 Models ALL Traditional API equivalent AcqrsD1_configTrigSource id channel trSlope AcqrsD1_getTrigSource id amp delayTime amp trSlope Discussion Studying the current range of the attribute may be needed to understand all of the possible values trSrcEnabled Purpose Control which input should be used for the trigger Prefixes Access Type Values channel amp ext RW string torr Ton Models ALL Traditional API equivalent AcqrsD1_ configTrigClass id sourcePattern AcqrsD1_ getTrigClass id amp sourcePattern Discussion The current trigger source can only be changed by turning On another source Programmer s Guide Page 93 of 100 acqiris trThres1 Purpose Control the trigger discriminator level for triggering Prefixes Access Type Values channel amp ext RW double In V Models ALL Traditional API equivalent AcqrsD1_configTrigSource id channel trigLevell AcqrsD1_getTrigSource id amp delayTime amp trigLevell Discussion For channels the trigger discriminator level can also be controlled relative to the current input range as defined by the full scale and offset This is done with trRelThres1 which
10. TrigResync amp reSync AcqrsD1_configAvgConfig instrID channelNbr TrigResync amp freeRun AeqrsDl acquire instrip long timeOut 1000 depends on conditions AcqrsD1_waitForEndOfAcquisition instriID timeOut Programmer s Guide Page 25 of 100 acqiris 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 AcqrsD1_readRealWform instrID 1 0 0 nbrPoints bckGndWform nbrReturnedSamples amp horPos amp SsampTime amp timeStampLo amp timeStampHi Restore the settings of the averager AcgrsDl conftigVertical instribD 1 fsr offset coupl bwidth AcqrsD1 conftigAvgConfig instrID channelNbr TrigResync amp reSsync 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 AcqrsDl acquire instriD long timeOut 1000 depends on conditions AcqrsD1_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 Backgroun
11. 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 AcqrsD1_config functions should be avoided because they can delay the start of the next acquisition A NOTE The AcqrsD1_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 22 of 100 acqiris Configure double sampInterval 1 e 9 delayTime 0 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 AcqrsD1_configHorizontal instrumentID sampInterval delayTime AcqrsD1_configMemory instrumentID nbrSamples nbrSegments AcgrsDl contigvertical instrumentiD channel fullScale offset coupling bandwidth AcqrsD1_configTrigClass instrumentID 0 0x00000001 0 O 0 0 DT E AcqrsD1_configTrigSource instrumentID channel trigCoupling trigSlope trigLevel 0 0 Comments Channel numbers run from to nbrChannels not from 0 Segment numbers however run from 0
12. amp enable Discussion channelUse Purpose Allows the RW client to activate de activate a channel Prefixes Access Type Values channel RW string on or oft Models ALL Traditional API equivalent NONE Discussion Deactivation of a channel can speed up clients and the server Deactivated channels do not have to have their data read out nor transmitted over the network Programmer s Guide Page 72 of 100 acqiris chAttenuation Purpose Functions as an additional multiplier for the conversion of raw ADC values to volts or other user units Prefixes Access Type Values channel RW double In dB Models ALL Traditional API equivalent NONE Discussion The raw integer data will be converted into a real value using several factors This one is in dB chBandwidthLimit Purpose Control the setting of the bandwidth limiter of a channel or external trigger input Prefixes Access Type Values channel amp ext RW double discrete In Hz 0 0 off Models ALL Traditional API equivalent AcqrsD1_ configVertical id bandwidth AcqrsD1_ getVertical id amp bandwidth Discussion The bandwidth is either given as 0 0 for no limit or a frequency value corresponding to the upper limit Programmer s Guide Page 73 of 100 acqiris chCoupling Purpose Control the coupling of a channel or exter
13. lt nbrSamplesInSeg If this is not sufficient GateLength is shortened to satisfy that condition 3 8 7 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 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
14. 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 13 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 AcqrsD1_getNbrChannels instrumentID amp nbrChannels Channel corresponds to channel 1 of module 0 Channel numbers increase first through module 0 then through modules 1 2 etc For Acqiris CC10x crates when a Multilnstrument is defined with AcqrsD1_multiInstrAutoDefine module 0 is always closest to the controller slot whereas with AcqrsD1_multilnstrDefine 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_Multilnput 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 13 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
15. so we decided to offer you the possibility to use our software to configure the settings Files created with the AcqirisLive program can be used To load a setup gt gt CallAcgiris LoadConfiguration Prompt for file gt gt CallAcqiris LoadConfiguration Filename To save a setup gt gt CallAcqiris SaveConfiguration Prompt for file gt gt CallAcqiris SaveConfiguration Filename 2 5 2 3 Calibration We added the possibility to do a calibration gt gt CallAcgiris Calibrate ID CalibrationType where ID is the module identifier 0 1 2 and CalibrationType can take one of the 3 values 0 calibrate the entire instrument calibrate only the current channel configuration 2 calibrate external clock timing Requires operation in External Clock Continuous Programmer s Guide Page 12 of 100 A acqiris 2 5 3 Process an acquisition 2 5 3 1 Create the AnalogInput object gt gt AI analoginput Aq 0 gt gt BUFFER SIZE 1000 gt gt BUFFER CNT 30 This command creates an AnalogInput object The first argument specifies that MATLAB should use the Acqiris Adaptor The second argument is the InstrumentID of the digitizer to use The two BUFFER constants are initialized for use in 2 5 3 4 below Alternatively gt gt AI analoginput Ag 0 cal false The option added tells the driver to skip the calibration A calibration is necessary wh
16. ETS and VxWorks real time systems there are sample programs for Visual Studio and Tornado respectively An Application Program Interface API hlp file with a shortcut named Acqiris Digitizer Driver Help is available and contains condensed descriptions of all of the interface functions 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 VXIplug amp play Systems Alliance VISA The visatype h include file can be found in the include directory created at installation 2 1 Visual C e Open either the project file GetStartedVC dsp or GetStartedAvgVC dsp in VisualC and build the project e Note that you should insert the line include AcqirisDlImport h at the beginning of every file that will access Acqiris Device Driver functions e The project should link to the AqDrv4 lib file 2 2 LabWindows CVI e Open the project file GetStarted prj in LabWindows CVI and build the project e Note that you should insert the line include AcqirisDlImport h 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 Getting Started Application Example Initialize Eel a Close eae Kee Configuration Status Action Data Utility ee e e rca eel Eel
17. Values RW integer 0 15 in LSB s Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcgqrsD1_configAvgConfig id channel DitherRange amp vdither Discussion The offset is dithered over the range v v in steps of 1 8 LSB axNbrRoundRobins Purpose Number of times to perform the full segment cycle during data accumulation Prefixes Access Type Values RW integer 1 to 65536 Models AP235 and AP240 with Averager option Traditional API equivalent AcqrsD1_configAvgConfig id channel NbrRoundRobins amp robin Discussion Programmer s Guide Page 62 of 100 acqiris axNbr Waveforms Purpose Number of waveforms to average before going to next segment Prefixes Access Type Values RW integer 1 to 65535 Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcqrsD1_configAvgConfig id channel NbrWaveforms amp triggers Discussion axP1Signal Purpose Define how the P1 Control signal should be used Prefixes Access Type Values RW String Disabled TIn AddSubCh1 Tn AddSubCh2 In AddSubCh1ch2 In AvgrTrigEnable In AvgrStartVetoEnable Out Average Models AP235 and AP240 with Averager option Traditional API equivalent AcgqrsD1_configAvgConfig id channel P1 Control amp function Discussio
18. be used with AcqirisMAQS the MATLAB interface and the SP201 Software Development Kit Programmer s Guide Page 6 of 100 acqiris The accompanying Programmer s Reference manual is divided into 2 sections jpanying 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 Visual Basic Visual Basic NET 1 3 Conventions Used 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 DC
19. before using the digitizer for any new acquisitions don t forget to calibrate the instrument with the function AcqrsD1_configTrigSource 3 16 Reading the Digitizer Temperature The temperature of a digitizer can be obtained with the following code long temperature will be in degrees C AcqrsD1_getInstrumentInfo ID Temperature amp temperature When multiple digitizers are combined via ASBus to a MultiInstrument 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 Acqiris recommends 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 Acqiris also recommends reading the temperature when the digitizer 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 57 of 100 acqiris 4 Attributes Module settings can be read and or changed through the use of attributes The attribute interface
20. 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 highest 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 long channel 1 gate 2 AcqrsD1_configAvgConfig instrumentID channel GateType amp gate long preSamples 0 postSamples 0 double threshold 0 0 in Volts 1 long thresEnable status AcqrsDl_ configAvgConfig InstrumentID 0 channel PreSamples amp preSamples status AcgrsD1_ configAvgConfig InstrumentID 0 channel PostSamples amp postSamples status AcgqrsDl_ configAvgConfig InstrumentID 0 channel Threshold amp threshold 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 AcqrsD1_ getInstrumentiInfo InstrumentID 0 SSRTimeStamp amp SSRtimeStamp
21. data Data can be read for both user and threshold gate operation using readMode ReadModeSSRW 7 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 8 6 4 Waveform storage 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 t
22. erni iiia ee E deiseds cnatou aus Audasind wadaial udu nutedeata hatin dae axP1Signal axP2Signal axSamples axSegments axStartDelay ARS ALE V CHOP MADE R A A otbesarscasadeausuasaveesegaxan sagaeaanies saasndessceaxdes eveobesdansssvassussnaessaas axStopDelay a cei E Gamintiaiie tinal adalat Gnd EEE O E OE AX TDA WAYS is cisvsevs canchscestnssveessuscnnasevsestecsy seas apevevsadvesons suas senesieceesstanideestussens aeab bens ay eas KEENNESS EAEE AX TTP RES VNC 4 es cds csbes Sab cseaesdastdesseiocanssusssdes te eaves Aecetes E T EE I CHAK IN VOrtD ata cisassevsds snessecs E danssvteedesd eaespsaiedaece E sxetessfownandasstdeede ia oudeen dap deeanevs cunduete stesaeee seed CHAK NOISCB ASG 23654 T sSeeceds fondesseas desde ce oast a0 EEA EOE E CHAXNOISEBASCE MAD S sinr arrer ENESE EA ERE IETS 69 CHAX TDC Histo Enable aca sessed sd 0564 cesses ccsstuds set sdeds ocessacs E E R ESS ERU RE IERTE ESTEN 70 Co 10 6 Bl 4 OES 0 61 ct eet oe 70 CHAXTDGHisto Min TOT sicsvcsiisschcssdsciiessshchsestanasi weiesh EES ESS E AETIA ESET EO EIE PEE REN EENE RETES 71 CHAX Threshold esses dssoeavdanedadscobedeassandsansssbadensaaccacsdasstesvacs seedanscaasanasoaaoes sees EA NEEN E ONI ee 71 CHAX Threshold Enable ss iscis cs sicanedasevtessasaeveedssacdsess coesness contanane s sxtiae ENEKE ENE EEEE EEEE ETEK REEERE testis 72 Channel S6 55 3 5 EE T chAttenuation chBandwidthLimit Programmer s G
23. execution with an error message 2 5 3 5 Read the Data Support for Adaptor properties is very limited The following properties are available from the Adaptor in read mode SampleRate SamplesPerTrigger NOTE Its value corresponds to samples segments segments segmentDescrIndex Using the property segmentDescrIndex you can access horPos timeStampLo timeStampHi Programmer s Guide Page 13 of 100 acqiris Refer to the section 3 10 Horizontal Parameters in Acquired Waveforms and section 3 11 Sequence Timestamps for detailed explanations on the interpretation of these values For averagers we provide nbrAveragedWaveforms from DataDescriptor The simplest way to read data for an acquisition with a single channel in a single segment is gt gt DataArray Time getdata AI gt gt set AI channel 0 segmentDescriIndex 0 gt gt trDelay CallAcgiris GetDouble ID trDelay gt gt Time Time get AI channel 0 horPos trDelay The first command returns all the data acquired together with a vector containing the time values for each sample acquired The DataArray will contain the measured values converted to the user units as follows valueInUserUnit userGain voltData userOffset voltData vGain rawData vOffset where userGain chScaleFactor chScale2ndFactor 10 Atenustion20 userOffset chScaleOffset vGain chFullScale 256 9e dataSize size in bytes of a
24. goes high after the first trigger is accepted for an average and drops back down when the last trigger s acquition is complete Programmer s Guide Page 64 of 100 acqiris axSamples Purpose Number of data samples per waveform segment in Averager mode Prefixes Access Type Values RW integer Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcqrsD1_configAvgConfig id channel NbrSamples amp samples Discussion May assume values between 16 or 32 and the available memory length in multiples of 16 32 The granularity is 16 for the AP100 AP101 and the AP240 AP235 in Dual Channel mode and 32 for the AP200 AP201 and the AP240 AP235 in Single Channel mode axSegments Programmer s Guide Purpose Number of waveform segments to acquire Prefixes Access Type Values RW integer Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcgqrsD1_configAvgConfig id channel NbrSegments amp segments Discussion May assume values between 1 and 8192 Page 65 of 100 acqiris axStartDelay Purpose Start delay in samples Prefixes Access Type Values RW integer Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcgqrsD1_configAvgConfig id channel StartDelay amp start Discussion May assume values between 0 and 33554400 16777
25. leave the acquistion in a well determined state for future operation The explicit acquisition processing readout sequence described above is shown in the following code Programmer s Guide Page 43 of 100 acqiris AqReadParameters readParams Read Definitions AqDataDescripto t dataDesc Returned waveform values long channel long nbrPeaks long waveformAr 1 segmentNumber 0 2 nbrGates nbrGates is defined by user ray 2 nbrPeaks long memoryBank 0 timeout 5000 timeout 5 seconds Insert whate and Tri ver is required for Vertical gger configuration AcqrsD1_configMode instrumentID 3 0 memoryBank AcqrsD1_acquire AcqrsD1_waitFor At this poin bool finished while finished memoryBank instrumentID Acquire into bank 0 EndOfAcquisition instrumentID timeout t you should check the return value false memoryBank 1 amp 0xl switch to other bank AcqrsD1_configMode instrumentID 3 0 memoryBank AcqrsD1_ acquire instrumentID start new acquisition AcgqrsDl_processData instrumentID 0 0 start processing AcqrsD1_waitForEndOfProcessing instrumentID timeout At this readParam readParam readParam readParam readParam readParam readParam readParam readParam readParam readParam readParam Ann HDHD HH HAHAHA HN N readParam reserved3 point you should check th
26. 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 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 gt Ins 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 Programmer s Guide Page 51 of 100 yo acqiris 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
27. of 800 waveforms of 5000 data points with a start delay of 128 samples Common Configure long nbrSamples 5000 nbrSegments 800 long startDelay 128 stopDelay 0 AcqrsD1_configMode instrumentID 7 0 0 AcqrsD1_configAvgConfig instrumentID 0 NbrSamples amp nbrSamples AcqrsD1_configAvgConfig instrumentID 0 NbrSegments amp nbrSegments AcqrsD1_configAvgConfig instrumentID 0 StartDelay amp startDelay 0 AcqrsD1_configAvgConfig instrumentID 0 StopDelay amp stopDelay Comments e The value of the third and fourth argumenta to AcqrsD1_configMode must always be 0 e When in AutoSwitch mode the following digitizer parameters are ignored e delayTime of the function AcqrsD1_configHorizontal is replaced by StartDelay and StopDelay Programmer s Guide Page 27 of 100 acqiris e nbrSamples and nbrSegments of the function AcqrsD1_configMemory are replaced by NbrSamples and NbrSegments in the function AcqrsD1_configAvgConfig e 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
28. 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 In many applications it can be ignored Refer to section 3 10 Horizontal Parameters in Acquired Waveforms for a detailed explanation of horPosReturn values have to be interpreted in the same way as for the other readout functions e Refer to the section 3 11 Sequence Timestamps for detailed explanations on the interpretation of segDesc gt timeStampLo Hi 3 8 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 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 For dataType 0 or 1 the amount of memory needed in bytes is arraySize gt segmentOffset nbrSegments 1 dataType 1 with arraySize gt nbrSamplesNom currentSegmentPad nbrSegments 1 dataType 1 and Programmer s Guide Page 35 of 100 acqiris segmentOffset nbrSamplesInSeg where e the currentSegmentPad depends on the acquisition configuration and can be determined using the following call AcqrsD1_ getInstrumentiInfo ID TbSegmentPad amp currentSegmentPad e the nb
29. p M N Extra Xfr M N Cpy 100 5 100120 0 012 100000 0 01 2306 us It is therefore more favorable to use the function AcqrsD1_readData for readMode 0 Transferring 1000 segments of 500 samples each recorded at 500 MS s M 1000 N 500 Xfr 0 012 Cpy 0 01 Ovhd yyy 100 OVA yg 5 Extra 240 2 96 216 T M Ovhd py M N Xfr 100000 6000 106000 us T Ovhd py M Ovhd pye M N Extra Xfr M N Cpy 100 1000 5 1000 716 0 012 1000 500 0 01 18 692 us The function AcqrsD1_readData for readMode 1 is about 5 times faster 5 3 Comparison Chart for Typical Transfers Time in ms 250 MHz Pentium 500 MHz Pentium 800 MHz Pentium of Samples T T R T T R T T R Segments Segment 1 200 0 20 0 22 1 10 0 10 0 12 1 13 0 06 0 08 1 17 1 1K 0 21 0 25 1 17 0 11 0 13 1 20 0 07 0 09 1 22 1 10K 0 30 0 52 1 72 0 20 0 31 1 56 0 16 0 23 1 45 1 100 K 120 3 22 2 68 1 10 2 11 1 92 1 06 1 70 1 60 1 1M 10 2 30 2 2 96 10 1 20 1 1 99 10 0 16 3 1 62 10 200 2 02 0 43 0 21 1 02 0 26 0 25 0 65 0 19 0 30 10 1K 2 10 0 67 0 32 110 0 42 0 38 0 73 0 32 0 45 10 10K 3 00 3 37 1 12 2 00 2 22 1 11 1 63 1 79 1 10 10 100 K 12 0 30 4 2 53 11 0 20 2 1 84 10 6 16 4 1 54 10 1M 102 300 2 94 101 200 1 98 101 163 1 62 100 200 20 2 2 47 0 12 10 2 1 67 0 16 6 45 1 37 0 21 100 IK 21 0 4 87 0 23 11 0 3 27 0 30 7 25 2 67 0 37 100 10K 30 0 31 9 1 0
30. should retrieve for every Multilnstrument additional information with the following calls Programmer s Guide Page 52 of 100 acqiris AcqrsD1_ getInstrumentInfo ID NbriInternalTriggers amp nbrintTrigs AcqrsD1_getInstrumentInfo ID NbrExternalTriggers amp nbrExtTrigs AcqrsDl1_ getInstrumentInfo ID NbrModulesInInstrument amp nbrModules nbrintTrigsPerModule nbriIntTrigs nbrModules nbrExtTrigsPerModule nbrExtTrigs nbrModules In a Multilnstrument composed of 4 DC240 2 channel 2 GS s digitizers you would get 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 functions AcqrsD1_configTrigSource and AcqrsD1_getTrigSource use the explicit trigger channel number with the internal trigger channel running from 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 an
31. status Vistring opticns status AcqrsDl_ getNbrPhysicaliInstruments amp nbrinstruments Initialize the digitizers for long i 0 i lt nbrInstruments itt char resourceName 20 sprintf resourceName PCI INSTR d i Ea status AcgrsDl_ InitWithOptions resourceName VI_FALSI VI_FALSE options amp instrumentID i The resource name must be of the form PCI INSTRO PCI INSTR1 etc If there are several digitizers on the system the order in which they are found is not obvious It depends on the Windows 95 98 NT4 2000 XP Configuration Manager implementation on the PCI bus topology in your computer and possibly on the BIOS 3 2 2 Identification by Serial Number All Acgiris digitizers are labeled with a unique serial number For PCI digitizers you will find it on the front panel and for CompactPCI digitizers 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 digitizer by specifying its serial number ViSession instrumentID AcgrsD1_InitWithOptions PCI SER10047 VI_FALSE VI_FALSE amp instrumentID Note that the serial number must be contiguous to the keyword SER leading zeros are accepted 3 2 3 Identification by Bus Slot Number While initialization by serial number is easy to implement it has th
32. takes values in FS and where 0 0 corresponds to the middle of the input range trThres2 Purpose Control the second trigger discriminator level for window triggering Prefixes Access Type Values RW double In V channel amp ext Models DC271 FAMILY Traditional API equivalent AcqrsD1_configTrigSource id channel trigLevel2 AcqrsD1_ getTrigSource id amp delayTime amp trigLevel2 Discussion For channels the second trigger discriminator level can also be controlled relative to the current input range as defined by the full scale and offset This is done with trRelThres2 which takes values in FS and where 0 0 corresponds to the middle of the input range Programmer s Guide Page 94 of 100 acqiris trThresUnit Purpose Control whether the relative or the absolute trigger discriminator level attributes should be conserved when changing the input range fullscale and or offset Prefixes Access Type Values channel amp ext RW double BEN OM SFS Models DC271 FAMILY Traditional API equivalent NONE Discussion When the value V is set for this attribute changing the input range of a channel i e changing the full scale and or the offset will keep the value in volts set for the trThres1 2 levels constant and adjust the corresponding relative values trRelThres1 2 On the other hand if the value FS is chosen a change in input range will im
33. than 200 waveforms Programmer s Guide Page 31 of 100 acqiris per second could be acquired because the application wastes time waiting for the acquisition to terminate C Waiting for Interrupt ViStatus status long timeOut 100 in ms status AcgqrsDl_ waitForEndOfAcquisition instrumentID timeOut if status ACQIRIS ERROR_ACQ TIMEOUT timeout stop STOP ACQUISITION This method combines low CPU usage with very good response time The function enables the digitizer 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 Acqiris recommends using AcqrsD1_waitForEndOfAcquisition since it is the most efficient method The interrupt latency is of the order of several us and no CPU time is wasted 3 7 4 Stopping Forcing an 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 acq
34. the gcc 3 2 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 sre 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 16 of 100 acqiris 3 Programming an Acqgiris Digitizer 3 1 Programming Hints When programming an Acgiris digitizer 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 o
35. 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 12 bit digitizers the system 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 frequen
36. timeoutCounter 100000 while done amp amp timeoutCounter gt 0 AcqrsDl_acqDone instrumentID amp done poll for status if timeoutCounter lt 0 timeout stop acquisition STOP ACOUISITION 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 according 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 int done 0 long timeoutCounter 100 while done amp amp timeoutCounter gt 0 AcqrsD1l_acqDone instrumentID amp done poll for status 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
37. x inputFrequency DP240 AP240 v x inputFrequency 1 x inputFrequency 1 generation 1 x inputFrequenc g p q y 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 AcqrsD1_getInstrumentInfo instrumentID ExtCkRatio amp ratio Programmer s Guide Page 49 of 100 acqiris 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 delayTime 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 AcgrsD1_ configMemory instrumentID 2000 1 AcgrsDl contigkxtClock instrumentiD 1 threshold 1500 2 0e 3 5 0e 7 AcqrsD1_acquire instrumentID start the acquisition AcqrsD1_waitForEndOfAcquisition instrumentID
38. 0 acqiris chAxNoiseBase Purpose Value in Volts of the value to be added in Noise Supressed Averaging Prefixes Access Type Values channel RW double In Volts Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcgqrsD1_configAvgConfig id channel NoiseBase amp base Discussion The value will be transformed into the ADC raw data equivalent of the voltage value chAxNoiseBaseEnable Purpose Allows the Noise Base value to be added to the data in Noise Supressed Averaging Prefixes Access Type Values channel RW string Oft ox TOn Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcqrsD1_configAvgConfig id channel NoiseBaseEnable amp enable Discussion Programmer s Guide Page 69 of 100 acqiris chAxTDCHistoEnable Purpose Enable the simple TDC mode for the channel Prefixes Access Type Values channel RW string OLE sor On Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcqrsD1_configAvgConfig id channel HistoTDCEnable amp enable Discussion chAxTDCHistoIncr Purpose Define the increment to be used in accumulating a simple TDC histogram Prefixes Access Type Values channel RW Integer Ler 2 Models AP235 and AP240 with Averager option AP100 AP200 Tradit
39. 0 idList 6 long nbriInstruments ViStetus statues ViString options cal 0 since calibration will be performed explicitly later status AcqrsDl_ getNbrPhysicaliInstruments amp nbrinstruments Programmer s Guide Page 20 of 100 acqiris Initialize the digitizers for long i 0 i lt nbriInstruments itt char resourceName 20 sprintf resourceName PCI INSTR d i le status AcgqrsD1_ InitWithOptions resourceName VI_FALSI VI FALSE options amp instrumentiID 1 i Now combine the first 3 digitizers in inverse order idList 0 instrumentip 2 idList 1 instrumentID 1 idList 2 instrumentID 0 viSession multilInstrID ViSession masterIndex instrumentID 1 lorig norinList 3 status AcqrsDl multiinstrDefine idList nbrinList masterindex email CAInSserry gt status AcgrsD1 calibrate multilInstrID The first part of the code above finds and initializes all individual digitizers as shown in section 3 2 1 Identification by Order Found Of course you could also use one of the other 2 methods of identifying individual digitizers After AcqrsD1_multiInstrDefine 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 physica
40. 12 AcqrsD1_ getControllO id 12 Discussion The value TrigOut should be chosen when the instrument is the PXI Star Trigger generator To trigger on the PXI Star signal the value TrigIn should be chosen Programmer s Guide Page 83 of 100 acqiris ctrllOTrOutLevel Purpose Control the offset of the Trigger Out signal Prefixes Access Type Values RW double In mV Models DC271 FAMILY 12 bit FAMILY Traditional API equivalent AcqrsD1 configControllO id 9 signal AcqrsD1_ getControllO id 9 amp signal Discussion Studying the current range of the attribute may be needed to understand all of the possible values ctrllOTrOutResync Purpose Control the synchronization of the trigger out signal with respect to the sampling clock Prefixes Access Type Values RW string OEE Mon Models DC271 FAMILY 12 bit FAMILY Traditional API equivalent AcqrsD1l_configControlIO id 9 qualifierl AcqrsD1 getControlIO id 9 amp qualifierl Discussion Use this attribute to control if the trigger output is resynchronized to the clock or maintains a precise timing relation to the trigger input Programmer s Guide Page 84 of 100 acqiris extCkRatio Purpose Give the ratio of the maximum external continuous clock sampling rate to the external clock input frequency Prefixes Access Typ
41. 216 in steps of 16 32 as explained below The limit is StepSize 1024 1024 1 The granularity is 16 for the AP100 AP101 and the AP240 AP235 in Dual Channel mode and 32 for the AP200 AP201 and the AP240 AP235 in Single Channel mode axStartVetoEnable Purpose Select the functionality for the Control I O Trigger enable Input Prefixes Access Type Values RW string Trigger enable Start Veto Models AP100 AP200 ONLY Traditional API equivalent AcgqrsD1_configAvgConfig id channel StartVetoEnable amp start Discussion This must be used in conjunction with ctr IOA Signal or ctrIIOBSignal being set to Trigger enable If set to Start Veto an Average Accumulation will only start after the computer starts the acquisition if the signal is high or if it goes high Programmer s Guide Page 66 of 100 acqiris axStopDelay Purpose Stop delay in samples Prefixes Access Type Values RW integer Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcgqrsD1_configAvgConfig id channel StopDelay amp stop Discussion May assume values between 0 and 2097120 1048560 in steps of of 16 32 as explained below The limit is StepSize 64 1024 1 The granularity is 16 for the AP100 AP101 and the AP240 AP235 in Dual Channel mode and 32 for the AP200 AP201 and the AP240 AP235 in Single Channel mode axTrigAlways Purpose Contr
42. 241A DC271 DC271A DP214 DP235 DP240 AP FAMILY AP240 AP235 AP100 AP101 AP200 AP201 12 bit FAMILY DC440 DC438 DC436 DP3 10 DP308 DP306 1 4 Warning Regarding Medical Use The Digitizer 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 substitute 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 Acgqiris 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 7 of 100 acqiris 2 Programming Environments amp Getting Started Acqiris supplies sample programs as a starting point for the development of user specific applications For Windows systems there are samples for the Visual C C Visual Basic LabWindows CVI LabVIEW and MATLAB For Phar Lap
43. 6 20 0 21 3 1 06 16 2 17 3 1 06 100 100 K 120 302 2 52 110 202 1 83 106 164 1 54 1000 200 202 229 0 11 102 15 8 0 16 64 5 13 2 0 20 1000 1K 210 46 9 0 22 110 31 8 0 29 72 5 26 2 0 36 1000 10K 300 317 1 06 200 212 1 06 163 170 1 06 8000 200 1616 182 0 11 816 126 0 15 516 105 0 20 8000 IK 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 Programmer s Guide Page 99 of 100 acqiris 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 If R gt 1 0 a loop over AcqrsD1_readData for readMode 0 is faster than AcqrsD1_readData for e R readMode 1 Time in ms 866 MHz Pentium of Samples T T R Segments Segment 1 200 0 03 0 04 1 22 1 IK 0 04 0 05 1 21 1 10K 0 12 0 17 1 45 1 100 K 0 98 2 12 215 1 1M 985 25 5 2 59 10 200 0 3 0 14 0 46 10 1K 0 35 0 27 0 76 10 10K 1 21 161 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 4 27 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 23 4 0 53 1000 5K 85 9 87 8 1 02 8000 200 457 648 0 14 8000 500 496 202 0 41 Comments Measured under the Linux OS Programmer s Guide Page 100 of 100
44. 78 of 100 acqiris chTimeOffset Purpose Functions as an additive constant to adjust the time of the data points of an acquisition Prefixes Access Type Values RW double In seconds Models ALL Traditional API equivalent NONE Discussion See the MATLAB discussion in the Programmer s Guide section 2 5 or section 6 2 4 of the SP201 Manual chUnits Programmer s Guide Purpose Allows the RW client to set the vertical units string for data values of a channel for the use of all clients Prefixes Access Type Values channel RW string any string Models ALL Traditional API equivalent NONE Discussion Digitizer data in volts can be subject to a linear transformation which also changes the units of the result This attribute stores the string associated with the new unit so that it is available to all client applications See the discussion in section 2 5 MATLAB or section 6 2 4 of the SP201 Manual Page 79 of 100 acqiris ckDelay Purpose Control the total number of samples digitized in a Continuous External clock acquisition Prefixes Access Type Values RW integer Models ALL Traditional API equivalent AcqrsD1_ configExtClock id delayNbrSamples AcqrsD1_ getExtClock id amp delayNbrSamples Discussion See section 3 11 of the Programmer s Reference manual ckThreshLvl Purpose Control the threshold le
45. Averager settings axDitherRange axP1Signal axSegments axStopDelay chAxInvertData chAxTDCHistoEnable chAxThreshold Not applicable chComment Programmer s Guide chBandwidthLimit chImpedance chScale2ndFactor chUnits chTime3rdOffset ckThreshLvl extInputFreq samples segments chFullScale trRelThres1 trSrcEnabled trThresUnit trTVStandard ctrlIOBSignal ctrl1OTrOutLevel channelName input axNbrRoundRobins axP2Signal axStartDelay axTrigAlways chAxNoiseBase chAxTDCHistoIncr chAxThresholdEnable chSetupName acqiris chCoupling chInput chScaleFactor chTimeOffset ckType extSamplingRate samplingFreq time Window trClass trRelThres2 trThres1 trT VField ctrllOPxiReflOMHz ctrOTrOutResync channelUse name axNbrWaveforms axSamples axStartVetoEnable axTrigResync chAxNoiseBaseEnable chAxTDCHistoMinTOT instrComment Page 59 of 100 instrSetupName tbComment mode trComment acqiris modeOption trSrcComment 4 3 Traditional API grouping of attributes Old API Uage AcqrsD 1 Attribute equivalent _configA vgConfig axDitherRange axNbrRoundRobins axNbrWaveforms axP Signal axP2Signal axSamples axSegments axStartDelay axStartVetoEnable axStopDelay axTrigAlways axTrigResync chAxInvertData chAxNoiseBase chAxNoiseBaseEnable chAxTDCHistoEnable chAxTDCHistoIncr chAxTDCHistoMinTOT chAxThreshold chAxThreshold
46. D1_ configHorizontal id delayTime AcqrsD1 getHorizontal id amp delayTime Discussion Studying the current range of the attribute may be needed to understand the current range Programmer s Guide Page 91 of 100 acqiris trRelThres1 Purpose Control the trigger discriminator level for triggering Prefixes Access Type Values channel RW double in of full scale Models ALL Traditional API equivalent AcqrsD1_ configTrigSource id channel trigLevell AcqrsD1_ getTrigSource id amp delayTime amp trigLevell Discussion The values for this attribute must be given in FS and where 0 0 corresponds to the middle of the input range The trigger discriminator level can also be set in volts This is done with trThres1 trRelThres2 Purpose Control the second trigger discriminator level for window triggering Prefixes Access Type Values channel RW double in of full scale Models DC271 FAMILY Traditional API equivalent AcqrsD1_configTrigSource id channel trigLevel2 AcqrsD1 getTrigSource id amp delayTime amp trigLevel2 Discussion The values for this attribute must be given in FS and where 0 0 corresponds to the middle of the input range The second trigger discriminator level can also be set in volts This is done with trThres2 Programmer s Guide Page 92 of 100 acqiris trSlope Purpose
47. Enable _configChannelCombination input _configControllO ctrllOA Signal ctrllOBSignal ctrlIOPxiRefl0MHz ctrIIOPxiStar ctrOTrOutLevel ctrOTrOutResync _configExtClock ckDelay ckThreshLvl ckType extInputFreq extSamplingRate _configHorizontal trDelay samplingFreq samplingIntv _configMemory samples segments _configMultInput chInput _configTrigClass trClass trSrcEnabled _configTrigSource trCoupling trRelThres1 trRelThres2 trSlope trThres1 trThres2 _configTrigTV trTVField trTV Line trTVStd _configVertical chCoupling chBandwidthLimit chFullScale chImpedance chOffset _getChannelCombination convertersPerChan input _getControllO ctrIOASignal ctrlIOBSignal ctrlIOPxiRefl0OMHz ctrIIOPxiStar ctrllOTrOutLevel ctr1OTrOutResync _getExtClock ckDelay ckThreshLvl ckType extInputFreq extSamplingRate _ getHorizontal trDelay samplingFreq samplingIntv _getMemory samples segments _getMultInput chInput _getTrigClass trClass trSrcEnabled Programmer s Guide Page 60 of 100 acqiris _getTrigSource trCoupling trRelThres1 trRelThres2 trSlope trThres1 trThres2 _getTrigTV trT VField trTVLine trT VStd _getVertical chCoupling chBandwidthLimit chFullScale chImpedance chOffset Programmer s Guide Page 61 of 100 acqiris 4 4 Detailed description of attributes Alphabetically ordered axDitherRange Purpose Defines the range of offset dithering in ADC LSB s Prefixes Access Type
48. In Acgqiris 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 NT 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 Digitizer User Manuals can create this file For details on channel and trigger source numbering please refer to section 3 13 ASBus Operation The master module is automatically chosen according to these rules 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 The function AcqrsD1_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 6 Manual Definition of MultiInstruments The function AcqrsD1_multilnstrDefine permits a manual definition of how to combine multiple digitizers with the ASBus Use a code fragment like the following one for the manual combination of digitizers ViSession instrumentID 1
49. Meg Mes ee E EA A Es Fecha eel Ea Obsolete The AqDx 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 AqDx driver 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 Programmer s Guide Page 8 of 100 acqiris 2 3 1 Getting Started VI File Edit Operate Tools Browse Window Help AE nj 13pt Application Font d tor Tarl E Resouce Name Channel Horizontal Settings Vertical Settings error out dataDesc PCT INSTRO g Number of Segments Full Scale status code BESESIPEA returnedSamplesPerSe Trigger Settings 35 000 zl a0 j EON horPos Trigger Source Trigger Coupling seas ahi Offset source AddrFirstPoint 1 078E 9 dinternal spc aenn co ms timeStampLo Trigger Slope eS dar e kis coppa r 3797121082 TrigLevel1 Trig Level 2 esa pi 4 rae P AMON eiie i on eae Read Mode i aay E a ye Gan e ADE 43 m 7 63E 5 5000 0 Seg 0 VOFFset 4000 0 A Seg 1 po 3000 0 Seg2 NbrSegments 2000 0 Seg 3 1000 0 teratom l0 0 0 reserved
50. 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 be activated using the defined base value The order of the calls to AcgqrsD1_configAvgConfig is not important since the final decision is taken when the acquisition is started Here is an example 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 AcqrsDl conftigAvgConfig instriID 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 AcqrsD1_configMode instrumentID 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
51. NbrSamples amp nbrSamples AcqrsD1_configAvgConfig instrumentID 0 NbrSegments amp nbrSegments AcqrsDl configAvgConfig instrumentID 0 StartDelay amp startDelay AcqrsD1_configAvgConfig instrumentID 0 StopDelay amp stopDelay Comments e The value of the second argument to AcqrsD1_configAvgConfig must always be 0 e When in buffered 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 e 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 e 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 e Although not shown her
52. Offset You can use these values to create a real time vector where the time of the first data point with resepect to the trigger is given by t0t horPos and the time between samples is as before The timeStamp values can be combined and used to measure the time difference between any pair of triggers in the acquisition Programmer s Guide Page 14 of 100 acqiris 2 5 3 6 Free Resources gt gt delete AI It s very important to free allocated resources when they are no longer needed 2 6 Phar Lap ETS The sample program is written for the Microsoft Visual Studio environment Open the project file GetStartedETS dsp The GetStartedETS cpp file contains a simple user program which e finds the Acqiris digitizers on the target machine e initializes the first or only one e configures some acquisition parameters and rereads some of them for checking e starts the acquisition e waits for it to terminate e reads the waveform e saves a binary disk file on the target with the data The program can be built downloaded and executed debugged from Visual Studio If FPGA bit files are required for the instruments installed they can be transferred to the target s hard disk using the pharemb monitor utility makehd The current version appears to work for Acqiris PCI modules only 2 7 VxWorks Tornado The VxWorks sample program is written for the Tornado environment The GetStartedVxW cpp file contains a simple user program wh
53. PerModule long inputNbr trigChan 1 nbriIntTrigsPerModule srcPattern moduleNbr lt lt 16 0Ox1l lt lt inputNbr else if trigChan lt 0 External Trigger trigChan trigChan long moduleNbr trigChan 1 nbrExtTrigsPerModule Q long inputNbr trigChan 1 nbrExtTrigsPerModule srcPattern moduleNbr lt lt 16 0x80000000 gt gt inputNbr else PROBLEM Note that moduleNbr and inputNbr start from 0 An industrial strength implementation should contain some checks on the range of trigChan and or inputNbr 3 14 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 14 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 su
54. Programmer s Guide Page 30 of 100 acqiris If you want to acquire several averaged waveforms under the same conditions there is no need to call the AcqrsD1_ 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 7 1 Starting an Acquisition Use the following line of code for starting an acquisition AcqrsD1_acquire instrumentID start the acquisition One such command is required for each module in use However if several digitizers are combined to a single MultiInstrument with ASBus only a single command is needed for the combined instrument 3 7 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 AcqrsDl getiInstrumentinio ID IsPreTriggerRunning amp PreTrigger 3 7 3 Waiting for End of Acquisition Waveforms cannot be read from the digitizer 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 int done 0 long
55. Programmer s Guide Page 9 of 100 acqiris 2 3 3 Accumulated Waveform Example VI gt AqDx Accumulated Waveform Example vi DER File Edit Operate Tools Browse Window Help ln R U Jame CI m pm ea foro doo 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 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 Interface vb is also available but there are no sample programs yet The Visual Basic sample program comes in 8 bit and 12 bit versions and consists of 3 major parts 1 The AcqrsD1Interface bas file that contains the Visual Basic version of the interface to the Acqiris supplied driver dll s installed in the System directory This file is needed for all Visual Basic projects involving Acqiris digitizers 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 DevCtriForm12 frm file with the code for a dialog box for the control of a complete di
56. S 22 3 4 Configuring Averagers cccceecceesseeceesceseceseesecaeceaecsaecseecaeeeseseseseeeseseaeeesecaeeaeceaeseecaeeeneees 24 3 4 1 Basic Configuration cccccccescceseceseceeecseecseeeseeseeeseesseceseeeeecaecsaecsaecsaecaeecseesaeseseseeeeereeeeeees 24 3 4 2 S11 a1 asap eeee e eee t cee per rer eee re erry se toe weer eey eerter ener see pe ater ey eeeerrer nerere reaver oar 25 3 4 3 Fixed Pattern Background Subtraction cccccscesssesseeesceeeceeeceeceaeeeseceeceeeseeeseseneeenses 25 3 4 4 Configuring Noise Suppressed Accumulation NSA ccccesccssecesecesecseeeeeeseeeseeeeeeeeeees 27 3 5 Configuring SSR Analyzers ccceccceeccessceseceeceseceeecseecseeeeeesseeeeeseeeeccaecsaecsaecaeecaeesseseneseneeenses 27 3 5 1 Acquisition Parameters cccccesccssccesscesecesecseecseecseeeseeseeseeeseeesecaecaecsaecaaecaeeeaeseneeeeesereees 27 3 5 2 Readout configuration ccccescesecssecseecseeeseesseeeeeseeeseeesecssecaecaecsaecaeecaeecaeeeeeseneeeneereees 28 3 5 3 Time SCAMS 4he2a2 5 oace AeeceslesteaMe te es esate eat ate a ede tee eae eens hae 29 3 6 Configuring AP101 AP201 Analyzers te eeeeeseeecsseeeceseeeeeceaeceessecaeesecneeeecsaeereaecateaeeaeentenes 29 3 7 Data ACQUISITION eceeccecceesceesceeeceseeseceseceseeusecnaecaeecaeeeseeeaeecesseessesaecaecsaecsaecaeecseeeseseseeeeeeereees 30 3 7 1 Starting an Acquisition ccccesccesecsseesceeseeseeeeeceecesecsse
57. Sparsing See also section 3 11 External Clock and Reference of the Programmer s Reference manual Programmer s Guide Page 86 of 100 acqiris input Purpose Control the active channels and number of converters per channel Prefixes Access Type Values RW string discrete Models DC135 DC140 DC241 DC241A DC271 DC271A DP235 DP240 AP235 AP240 Traditional API equivalent AcqrsD1_ configChannelCombination id usedChannels AcqrsD1_ getChannelCombination id amp usedChannels Discussion Studying the current range of the attribute may be needed to understand all of the possible values name Purpose Allows the RW client to set the name of the instrument for the use of all clients Prefixes Access Type Values RW string any string Models ALL Traditional API equivalent NONE Discussion The RW client can set a name that can then be known by all the other clients e g for better human identification of the instrument Programmer s Guide Page 87 of 100 acqiris samples Purpose Control the number of valid data points per segment in an acquisition Prefixes Access Type Values RW integer Models ALL Traditional API equivalent AcqrsD1_ configMemory id nbrSamples AcqrsD1_ configHorizontal id amp nbrSamples Discussion The maximum number of samples depends on the current number of segments in a sequenc
58. 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 asynchronously 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 4 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 a ways 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 2 VCO time interval not 4 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 AcgrsDl configkXX Jj configure other parameters AcqrsD1_configMode instrumentID 0 0 1 AcqrsD1_ acquire instrumentID AcqrsD1_waitForEndOfAc
59. acqiris XZ130 ACQIRIS PROGRAMMER S GUIDE Programmer s Guide ZM020130C Rev A acqiris December 2004 The information in this document is subject to change without notice and may not be construed as in any way as a commitment by Acqiris While Acqiris 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 Acgiris SA 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 Acqiris 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 acqiris com Trademarks product and company names listed are trademarks or trade names of their respective companies Acqiris Headquarters Acqiris USA Acqiris As
60. aging block size The ditherRange value may be between 0 no dithering and 15 max dithering Please refer to the next section for further explanations Page 24 of 100 acqiris 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 instrumentID 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 Oavg 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 t
61. aitForEndOfAcquisition 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 AcqrsD1_configMemory instrumentID 40000 1 AcqrsD1 conftigExtClock instrumentiID 4 threshold 0 33 366 33 366 AcqrsD1_acquire instrumentID start the acquisition gt Generate 20 bursts of 2000 clock pulses at 33 3 MHz At the end you need to inform the host computer to terminate the acquisition and AcqrsD1_ stopAcquisition instrumentID AcqrsD1 readxXXxXWform instrumentID ah ae Ne Note that the sampling rate and the time between bursts have no incidence on the configuration parameters of the digitizer i e they appear nowhere Example for Termination 2 if you wanted to acquire 5000 waveforms of 200 data points each you would write AcqrsD1_configMemory instrumentID 100000 1 xtClock instrumentip 4 threshold 0 0 0 01 AcqrsD1_acquire instrumentID start the acquisition fe AcqrsD1_configl 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 instrumentID timeOut AcqrsD1_ readxXXxXWform instrumentID ve ee US The 320 640 on 2 GS s or 1280 on 4 GS s digitizers extra clocks could be generated by 1 or
62. alled Aq ModeLive we offer the possibility to open an Instrument Settings window through which you can modify your instrument attributes The available attributes are presented in chapter 4 ATTRIBUTES Please note that not all attributes mentioned there are available for all instruments in all environments A file with the suffix AqSettings is provided together with the MATLAB examples and is used to define the format of the Instrument settings window Note that the Instrument Settings window is not a modal window so it can remain open during acquisitions Here is the code to display the Instrument Settings window gt gt CallAcqiris InstrumentSettings Attributes can also be read or modified with commands To get all instrument attribute names gt gt attributeList CallAcqiris AttributeList ID To get an attribute s range gt gt attrRanges CallAcqgiris AttributeRanges ID attrName To retrieve an attribute value gt gt value CallAcgiris GetString ID attrName gt gt value CallAcgqiris GetInteger ID attrName gt gt value CallAcgqiris GetDouble ID attrName To modify an attribute gt gt CallAcqiris SetString ID attrName value gt gt CallAcqiris SetInteger ID attrName value gt gt CallAcqiris SetDouble ID attrName value 2 5 2 2 Loading and Saving a Setup The way offered by MATLAB to set Properties Settings is not very user friendly
63. ame as with an internal reference clock Programmer s Guide Page 48 of 100 acqiris 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 9 0 10 2 MHz 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 risetime 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 3 12 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 and second generation digitizers of the DC271 FAMILY models DC135 DC140 DC211 DC211A DC241 DC241A DC271 DC271A DP214 DP235 DP240 the AP240 AP235 signal analyzer platforms and the 12 bit FAMILY DC440 DC438 DC436 DP310 DP308 DP306 since their behavior in this mode is quite different AP200 AP201 AP100 AP101 Averagers and Analyzers are considered to be first gene
64. an 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 configuring 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 3 14 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 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
65. an Gis 15 2 7 3 Running the Program ccecccesccssessseesseeseeeeceeeeeseceseceaecaecaecaecsecaecaecaeecaeecaeseseseeeeneeeneeeas 16 Dee ETE D E E A se ccesceteeuas E E E E E fetvess N alt 16 3 PROGRAMMING AN ACQIRIS DIGITIZER ccccsssessssssssscsessccssesesssssecsscesessccssesossseseessnes 17 3 1 Programming PMs x os sesa EA a e EE EAEE E ove 17 3 2 Device Initial ations x ressesie sr eies s tgs essays cand ERTE E EEEE E aieia 17 3 2 1 Identification by Order Found sseni iseina ieies reistassen 18 3 2 2 Identification by Serial Number ccecceceesseecesseeeseeeeeeeeesecesecaecaecaeecaeesaeeeseseeeeneeeneeeas 18 3 2 3 Identification by Bus Slot Number cccceecceeeesceeseeeseeeeeseceeecaecaecaeecaeecaeeeseeeeeeneeeeeeeas 18 3 2 4 Firmware initialization AP FAMILY 12 bit FAMILY sesser 19 3 2 5 Automatic Definition of Multilmstrument 00 cc ecceseeceseseeeeecseeeeceeeeecaeeeceaecateeeeneeaeenee 19 3 2 6 Manual Definition of Multilnstruments eececceseeseesecseeeeceeseecaeeeceaeceeeeceaeceeeeeeneeerenee 20 3 2 7 AqGeo map file pOSitioMiNg ce ceccecceseeceeecessceeecesecesecseceaeceaecseecaeeeseeeeeseeeeeeeeseeneeeeeeees 21 3 2 8 Simulated DeVviGes si i235 s2 20505555 G50 eeen aean ee aeea E Tea aE NEEE aS 22 3 2 9 Terminating an Applications c os cc ccccescecsssecceccacsesescacocesceecedandecdeus eKA iaus EE einate sisis 22 3 3 Device Com Quratiom sssrin Eae E EEE E EREE ETER
66. cDevice instrumentID NULL FPGADirectoryName 2 As a final step you should now calibrate the instrument which will cause the FPGA files to be loaded Status AcgrsD1 calibrate instrumentID 3 2 5 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 of instruments found including individual modules without ASBus connections You still need to retrieve the instrumentID for each instrument by calling the function AcqrsD1_InitWithOptions afterwards as shown below Programmer s Guide Page 19 of 100 acqiris viSession instrumentID 10 long nbriInstruments ViStatus statue ViString options status AcgqrsDl_ multilInstrAutoDefine amp nbrinstruments Retrieve the digitizer identifiers for long i 0 i lt nbriInstruments itt char resourceName 20 sprintf resourceName PCI INSTR d i EJ F status AcgrsD1_ InitWithOptions resourceName VI FALSI VI_FALSE options amp instrumentID i The calls to AcqrsD1_InitWithOptions are needed to obtain the instrumentID s The physical digitizers were already initialized when AcqrsD1_multiInstrumentAutoDefine was called The digitizers within a single MultiInstrument are numbered from 0 to NbrModulesInInstrument 1
67. ceaeceaeceeecaeecaeeeaeseeeeeeeeeeeseeneeneeaees 31 3 7 2 Checking if Ready for Trigger cccccccsecssesseeeseeseeeseeeecsecesecneeeaecaecaeecaeesaeeeseeeeeeeeeeeeeees 31 3 7 3 Waiting for End of Acquisition cccccccecscessseescessceseceseceaecaecseecaeesaecseecaeecaeeeseeeneeeeeeeeeees 31 Programmer s Guide Page 3 of 100 acqiris 3 7 4 Stopping Forcing an Acquisition ccceecceesceeecesecesecesecaeecseeeeeeeeeeeeeeaeeeseeeeeeereeeseeeenteenaees 32 3 7 5 Analyzer Autoswitch Mode 05 66ccccssciesceccsceacevenccacecsaceadeteedsadecdacescedeadeceecessatseteadeedscestuens 32 3 8 Data Readoutersicssc cin antici citior dati Se ik RRR adie BE Gi ee ie e 34 3 8 1 Reading Digitizer Waveforms with the Universal Read Function c ccccssesseseeeseee 34 3 8 2 Reading Sequences of Waveforms ccccceessessceseceseceecesecenecaeecaeecaeeeeeeeeeeeeeeeeeserenseeneeeas 35 3 8 3 Averaging Waveforms in a Digitizer cee ccceccceesceeeceseceseceseceeecseecaeesaecaeecaeeeaeenseeseeeneeees 37 3 8 4 Reading an Averaged Waveform from an AVeragetr c ccccseeseseeeseeeeeeeeensecesecneeeeeeneeses 37 3 8 5 Reading a RT Add Subtract Averaged Waveform from an Averager seeseeeerseeeeereeeeee 39 3 8 6 Reading SSR Analyzer Waveforims cccccceccessessseeseeesceseceecesecnaecaecsaecseeeaeeeseeeeeeneeeeeeeas 39 3 8 7 Reading AP101 AP201 Analyzer Waveforms cccccccceescessceseceseceseceeecneeeaeeeseee
68. 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 5 2 Examples A DP210 in a 800 MHz Pentium Transferring single records of 100 000 samples recorded at 2 GS s M 1 N 100000 Xfr 0 01 Cpy 0 00625 OVI pyyy 62 5 Ovhd yy 3 125 Extra 480 192 672 T M Ovhd py M N Xfr 62 5 1000 1063 us T Ovhd y4 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 pu 62 5 Ovhd yy 3 125 Extra 480 192 672 T M Ovhd py 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 is about 2 7 times faster 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 Programmer s Guide Page 98 of 100 acqiris M 1 N 100000 Xfr 0 012 Cpy 0 01 Ovhd pu 100 Ovhd q 5 Extra 240 10 96 120 T M Ovhd y4 M N Xfr 100 1200 1300 us T Ovhd pu M OVA
69. cqrsD1_configMode AcqrsD1_configAvgConfig AcqrsD1_acquire instID AcqrsD1_processData instID 0 1 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 instID timeout AcqrsD1_readData instID 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 100 acqiris status AcqrsD1 acquire InstrumentID Start the acquisition processType 0 for loop forever status AcqrsD1_ processData InstrumentID processType 1 status AcqrsD1 waitForEndOfProcessing InstrumentID timeout status AcqrsD1 readData InstrumentID channel amp readPar adcArray amp dataDesc amp segDesc 3 7 5 1 AutoSwitch mode without processing To keep the same interface with and without processing the processing step is kept but can be reduced to a dummy processing Thus the software must wait for the end of processing even if the processing mode is set to NO_PROCESSING 3 7 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 wait
70. cy as the value inputFrequency set in the function call above AcqrsD1 calibrateEx instrumentID 2 0 0 The function AcqrsD1_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 DC271 FAMILY digitizers 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 1 e Isamples In this case the trigger timestamps of the sequence acquisition mode are not available Depending on the ratio of sampFrequency inputFrequency 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 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 12 3 External Clock Start Stop The start stop external clock mode clockType 4 permits the application of a
71. d 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 IN1 Internal trigger channel 1 1 IN2 Internal trigger channel 2 2 4 IN 3 IN 4 IN 5 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 digitizers 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 Programmer s Guide Page 53 of 100 acqiris if teigchen gt 0 Internal Trigger long moduleNbr trigChan 1 nbriIntTrigs
72. d buffer double bckGndWform nbrPoints AcqrsD1_readRealWform instrID 1 0 0 nbrPoints bckGndWform nbrReturnedSamples amp horPos amp SsampTime 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 instrumentID channel amp readParams waveformArray amp wfDesc amp segDesc you must correct the average as follows corrWform i waveformArray i bckGndWform i 128 nbrAvgwWforms 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 Programmer s Guide Page 26 of 100 acqiris 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
73. d with the function AcqrsD1_configMode instrumentID mode 0 0 The value mode can be set to 0 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 20 000 data points with a dithering range of 15 ADC LSB s and a start delay of 128 samples for an AP100 Configure AcqrsD1_configAvgConfig instrumentID AcqrsD1_configAvgConfig instrumentID AcqrsD1_configAvgConfig instrum AcqrsD1_configAvgConfig instrumentID AcqrsD1_configAvgConfig instrumentID long channelNbr 0 nbrSamples 20000 nbrWaveForms 1000 long ditherRange 15 trigResync 1 long startDelay 128 stopDelay 0 AcqrsD1_configAvgConfig instrumentID channelNbr NbrSamples amp nbrSamples channelNbr NbrWaveforms amp nbrWaveForms channelNbr Range amp ditherRange entID TrigResync channelNbr amp trigResync channelNbr StartDelay amp startDelay channelNbr StopDelay amp stopDelay Comments Programmer s Guide The value channelNobr 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 delayT
74. dhigh tstamp dlow ViReal64 low dhigh ViReal64 high tsamp dlow 4294967296 0 dhigh 3 12 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 either on 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 an amplitude of at least 2 V peak to peak 1 V for the DC 271 Family the 12 bit Family and the AP Averagers and Analyzers The inputThreshold value should be set to the center of the signal 3 12 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 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 s
75. e 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 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 3 7 Data Acquisition Digitizer 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 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
76. e acquisition Studying the current range of the attribute may be needed to understand the current range samplingFreq Purpose Control the time between two data points in an acquisition Prefixes Access Type Values RW double In Hz Models ALL Traditional API equivalent AcqrsD1_ configHorizontal id delayTime sampInterval AcqrsD1_ configHorizontal id amp delayTime amp sampInterval Discussion The samplingFreq is the inverse of the sampInterval Studying the current range of the attribute may be needed to understand all of the possible values Programmer s Guide Page 88 of 100 acqiris samplingIntv Purpose Control the time between two data points in an acquisition Prefixes Access Type Values RW double In seconds Models ALL Traditional API equivalent AcqrsD1_ configHorizontal id delayTime sampInterval AcqrsD1 configHorizontal id amp delayTime amp sampInterval Discussion Studying the current range of the attribute may be needed to understand all of the possible values segments Purpose Control the number of segments in an acquisition Prefixes Access Type Values RW integer Models ALL Traditional API equivalent AcqrsD1 configMemory id nbrSegments AcqrsD1 getMemory id amp nbrSegments Discussion The number of segments chosen may coerce the number of samples per segment in the acquisition Pr
77. e Values RO double LsO 025 Models ALL Traditional API equivalent NONE Discussion This number can depend on the model and the convertersPerChan value extInputFreq Purpose Inform the driver of the external continuous clock frequency Prefixes Access Type Values RW double In Hz Models ALL Traditional API equivalent AcqrsD1 configExtClock id inputFrequency AcqrsD1_ getExtClock id amp inputFrequency Discussion See section 3 11 External Clock and Reference of the Programmer s Reference manual Programmer s Guide Page 85 of 100 acqiris extSamplingRate Purpose Control the desired sampling rate when in external continuous clock mode Prefixes Access Type Values RW double In Hz Models ALL Traditional API equivalent AcqrsD1_ configExtClock id sampFrequency AcqrsD1_ getExtClock id amp sampFrequency Discussion See section 3 11 External Clock and Reference of the Programmer s Reference manual extSparsing Purpose Alternate to control the desired sampling rate when in external continuous clock mode Prefixes Access Type Values RW double Models ALL Traditional API equivalent AcqrsD1_configExtClock id sampFrequency AcqrsD1 getExtClock id amp sampFrequency Discussion The values are such that extSamplingRate extCkRatio extInputFreq ext
78. e drawback that anytime a digitizer is replaced by another one e g if a failure occurred the program has to be modified Acqiris offers the possibility of specifying the logical position of the device at initialization ViSession instrumentID AcqrsD1_InitWithOptions PCI BUSO02 SLOT06 VI_FALSE VI_FALSE m instrumentin 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 Programmer s Guide Page 18 of 100 acqiris ViSession instrumentID char name 20 long serialNbr busNbr slotNbr AcqrsD1_getInstrumentData instrumentID name amp serialNbr amp busNbr amp SlotNbr 3 2 4 Firmware initialization AP FAMILY 12 bit FAMILY In these modules the on board FPGA s field programmable gate arrays contain processor logic 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 AcqrsD1_Init can be used The name for the FPGA program file is a synthesis of m
79. e return value dataType ReadReal64 readMode ReadModePeak nbrSegments 1 firstSampleInSeg 0 segmentOffset 0 firstSegment 0 Read first segment nbrSamplesInSeg 2 nbrPeaks pos and neg peak dataArraySize 2 sizeof double nbrPeaks segDescArraySize 0 flags 0 reserved 0 reserved2 ll oO se AcqrsD1_readData instrumentID channel amp readParams waveformArray amp dataDesc NULL analyse and store data AcqrsD1_waitForEndOfAcquisition instrumentID timeout read original data if desired o echeck 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 Programmer s Guide Page 44 of 100 acqiris 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 P
80. eak 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 negativePeakPos amp waveformArray 4 8 i Programmer s Guide Page 45 of 100 acqiris 3 9 Trigger Delay and Horizontal Waveform Position 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 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 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 nbrSamp
81. ed lect E EO ENES 87 HAE oa cnn he es A O one soins E EE A tune tussueze E A A 87 SAMPLES ieai Foss 25 e E E T OE OEE E ened as 88 sampling Ered Ss eicesscrscatactwctses dee ctcadstiescesssvetseasewceseacewassugscwances suede tau cauesseudeuesge veces syausudotwusacstocet sua sabeseeasuvetetuccwansess 88 Samp ling Unt casesetssied aacvebatancads colsseteseriseas iededs coaches doledetssa gaa aeioteds ioscaeeelasassiabaaas whole bats ETDE N Sib FSE S 89 segments timeWindow MCE LAS EENEN EER PEE AMEENAA AIAS NENE E NEEN IONES nas capa ns ae ea ae S aes ATS OUP 11D PEPENE S NE AEAEE EEE E EN ARO A E AE AREE AE EBE E A EE E A A E S te T E E saeee gates trRelThres1 za 92 tReIThres2 onosai rare Eria E AE E E SE ESE UREA Aaa ENS 92 TES LO 1E E E E T a E E E E E LE TEEN 93 ESIko mnel o l ES PA EAE E E A EEE EEE E 93 HE B nia AA E EE E E E E E E Heute A A 94 MoE I n ha EE 2s as SA O AEE E OEE EAEE NESTANE E AIEEE NEA EAEE SEE SEAE ENNE EAEE NNE AEE 94 t THreSUTit oeeie a E E NEE EE A E E A TE ed a 95 ED ATA ATE o E TE EE EEE 95 te BAYA Lit sy E E E E E E E E EA EE EE AN EEEE E 96 TE DV SUC AN AR A EENE ES E AE O E IEE E E E OEIT E ES E E sux cass sotnates eases 96 5 APPENDIX A ESTIMATING DATA TRANSFER TIMES seeeessesesssesescosssseoesesesessossssosssseese 97 Sil Principles amp Formulas isss nesnese en eeen pr a EE E EEEE EEEE EEEa 5 2 Examples 5 3 Comparison Chart for Typical Transfers Programmer s Guide Page 5 of 100
82. eeeneeeneeees 40 3 9 Trigger Delay and Horizontal Waveform Position cccccecceesseeseeeeceeeceseceseceeceeeseeeeeeneeeeeees 46 3 10 Horizontal Parameters in Acquired Waveforms ccsccesescsseseeeeeceeeeeceeeeceaeeeesseeaeeaeeneeeees 46 3 11 Sequence Timestamps cecccscecssesscescesseeeeeeeeceecesecesecaeceaecaaecaeecaeeeaeseneeeeeseeeeeeseeeeeerseeenaees 47 3 12 External Clock and Reference 0 ecccescceseeesecssecseeeseeseecaeesseeeeesseeeseceseeeseeaeeaeeaecneeceeeseeens 48 3 12 External References icc1c avec des used RG aR sic RG ee esha 48 3 12 2 External Clock Continuous cccccscecssessceesceeecesecesecesecaeceeecanecaeecaeseneeeeeeaeeeeeeeneseeeereeas 49 3 12 3 External Clock Start Stop cccccesccssesssesseesseeeseeeeeeeeceeeeseceseceaeeeaeceaecaaecaeecaeesseseneseeeeneees 50 3 13 ASSBUS Operatn On ssr Sve cieans s2cuse thee e a aaea aE aa stan e aE E SEERE iS 52 3 13 1 Channel Numbering with ASBus ssssessesessseeeseseseessessrssseesssstsessenessreressesseseeseenesseeresse 52 3 13 2 Trigger Source Numbering with ASBuUS eseessesesssesesssrserssesrssseesessrsressesseserseesesseseesse 52 3 14 Special Operating Modes ccccesccsceesseesseseeeesceseeeecesecesecaeceaecseecaeecaeeeaeeeeeeeeeeeeeeereneeneenaees 54 SAAT Freguenty Contele erreien o Teen nnie ia e e a Ca Eai riene Toa eN ea Teei e ei A cous 54 3 14 2 Starton Trigger seviscccccscssccsteesstcssccas cca
83. en first using an AnalogInput object ina MATLAB session However since the calibration settings remain in effect until the driver is unloaded e g when closing MATLAB this can be used to avoid recalibration at each execution of an m file For best measurement quality the calibration should be repeated after any significant temperature drift Note that unless calibration is deactivated all detected instruments will be calibrated 2 5 3 2 View the Instrument Information gt gt dagqhwinfo AI This call will display information about your digitizer 2 5 3 3 Configure and Add Channels gt gt AddChannel AI i where i 1 n This command is used to create a channel You can create as many channel objects as there are channels on the given instrument 2 5 3 4 Start an Acquisition gt gt set AI BufferingConfig BUFFER_SIZE BUFFER CNT gt gt start AI gt gt waittilstop AI TIME OUT NOTE Although you don t need to understand the first command be sure that this command is present for each start Al because it is needed for engine buffer allocation and it must be done if samples or segments have been changed Appropriate values should be set once and subsequently reused The number of buffers must be at least 2 The second command starts the acquisition and the third waits for the end of the acquisition You can specify a timeout If the timeout occurs MATLAB terminates the file
84. es 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 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 AcgrsD1_configXXX configure other parameters AcqrsD1_configMode instrumentID 0 0 2 AcqrsD1_ acquire instrumentID AcqrsD1_stopAcquisition instrumentID 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 segme
85. esesossesoesesescsesscssssesesese 8 2l Visual Cao exis sneen iea aena EA EEEa re teace steeds eave snes Geb EE EE EE on eae 8 2 2 LAB WANAOWS CV Lo secvscctscs ces ccseeueet sie colee seeteonsochccgeversieiceshoctees sau EREE EEEE EREE cee 8 e Gr oh 0 Sh er a N frrereter reat rrer tre isevere ertcnereteeve E ister fr rere ter vest r renters 8 2 3 1 Gethin Started Viera eases nae e ets a eee 9 2 3 2 EXAMPLE SCOPE VLassssccecss5secscpccuees Soi eiei soenseio sd ucdhsustesshollh igdesasdeveesiobaehevseveestihiets 9 2 3 3 Accumulated Waveform Example V1 cccsccesecsseesseseeeeeeeeeeeeeeseeeneeeeeeeeeeeeeeeeeeeseeeenaees 10 DA Visual Basi eee cccecsee tees eat estes eee eee sees 10 25 MAILA B ere eee ree tee ee er eee eerie eres eee ee a ree errr ee peer rye 11 2 5 1 Examples irae aieea ap EE E EE EREA cadbesd ctagievas SOENE EEEE Taa ESE 11 2 5 2 Setup and Settings sisses insons issides eip r iR rE S EES EREE EE iR EESE SEEE oiis 12 2 5 3 Process AN ACQUISITION cceeccesecesecececseecseeeseeeseeeesseesaeenseceaecsaecaaecaecaaecaeecseeeseseneeeeeeeeeas 13 2 6 Phat Lap ETS seminee e E E ar N E e EEE EEEE ENS 15 2 7 VxWorks Tornado ccccccecccesccesecesecssecscecseeeseeeeeeseceseensecesecaecaeceaecseecaesaecaeecaeseaeeeeeeeeeserseeaees 15 2 7 1 GOMPIAM Y aA casdecss cangeuse vse eds cxazuge ade T vas taces chatanescsatangeceameeadaeeniaass 15 2 7 2 Loading oine enara need ees aie das hed ain Eaa Eae ee Mai chile
86. etMemory ID amp nbrSamplesNom amp nbrSegmentsNom readPar gt dataArraySize nbrSamplesNom currentSegmentPad l nbrSegments Programmer s Guide Page 36 of 100 acqiris here we show the malloc explicitly dataArrayP char malloc readPar gt dataArraySize readPar gt segDescArraySize sizeof AqSegmentDescriptor nbrSegments status AcgqrsDl_ readData instrumentID 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 8 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 single 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 ave
87. gensscgavecsscesdevssesageaaecuass scaveesscastanssccancean ceaduassseateestcass 55 SAAB Seguence Wrap sse eonen togeier accu Sues sdavenas Sochised soda ess Denie naoa aE EE RAE Reien 55 3 15 Readout of Battery Backed up MemMores cceecceesseesceeseeesceeceseeeaecesecaeecaeeeaeeeeeeeeeenseeeeeees 56 3 15 1 Preparations before Power Off ccccccccssesscessceesceseceeceseeeseceaecaaecaeecaeeeaeeeeeeaeeeseenseseneeneeeas 56 3 15 2 Recovery after Power Off cc ccecccecccseessesseeeecessceeceseceseceaecaecsaecaecsaecaaecseecaeeeneeneeseeeeeeenes 57 3 16 Reading the Digitizer Temperature cccccccecseesceeseeesceeeeeecesecesecaecaecaeecaeeeaeeeneeneeenneeereeas 57 d ATTRIBUTES scssesieciscsncczesesisessetece sacuessvovessossaacsesie odes stcssvezeobtsescecssssasesasseede cbesvvacedtesedesuesctsteadessssesies 58 4 1 Attribute dependencies and coerced values cceeccescceseeeseeesecseeeeeeeeeeseeeeeeseenseeneeeeneeenteensees 58 4 2 Functional grouping of attributes ccc cccecsesseeceseceeeceeecesecesecaeceaecsaecaeecaeeeeeseeeseeesereeeeeneeserens 59 4 3 Traditional API grouping of attributes eceecceeceseeeeceeeceseceseceeceeecaeeeseeeeeeeeeeeeeeeenereneeenaees 60 4 4 Detailed description of attributes Alphabetically ordered ccccecseeseeseeceeeeeeeeeeeseeeeenteensees 62 RDVIT MCT RAT GS Pag Soa cas awh acca ede cane EAE N ees sarap EE A nse sites scab eau AEE R axNbrRoundRobins OX NDr Waveforms
88. gitizer 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_InitializeQ 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 AcqirisShowl vbp project file in the AcqirisLive VB directory and choose Open e After the project is loaded use the menu Run 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 Digitizer 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 Programmer s Guide Page 10 of 100 acqiris 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 wi
89. hat 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 The function AcqrsD1_multilInstrumentAutoDefine is recommended for this task It 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 of instruments found including individual modules without ASBus connections You still need to obtain the instrumentID for each instrument by calling the function AcqrsD1_InitWithOptions afterwards For details please refer to the section 3 2 5 Automatic Definition of MultiInstruments Alternatively you can initialize each module individually with the function AcqrsD1_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 6 Manual Definition of MultiInstruments Programmer s Guide Page 17 of 100 acqiris 3 2 1 Identification by Order Found If you don t know which and or how many Acqiris digitizers are present on the machine use this code fragment viSession instrumentID 10 long nbriInstruments ViStatus
90. his waveform from each subsequently 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 AcqrsD1l getVertical instriID 1 amp fsr amp offiset amp coupl amp bwidth AcgrsDl contigVertical instriD 1 fsr offset 0 bwidth AcqrsD1_getAvgConfig instrID channelNbr
91. ia Pacific Acqiris SA Acqiris LLC Acqiris Pty Ltd 18 chemin des Aulx 234 Cromwell Hill Rd Suite 7 Level 1 CH 1228 Plan les Ouates P O Box 2203 407 Canterbury Road Geneva Monroe NY 10950 1430 P O Box 13 Switzerland USA Surrey Hills 3127 Australia Tel 41 22 884 33 90 Tel 845 782 6544 Tel 61 3 9888 4586 Fax 41 22 884 33 99 Fax 845 782 4745 Fax 61 3 9849 0861 Copyright December 2004 Acqiris SA All rights reserved Programmer s Guide Page 2 of 100 acqiris CONTENTS 1 INTRODUCTION sisscsscossscsscosssvsscssosnsscososessvesonrsieesoorsecesoseseceaseestvesonnsstedoensseesoessseesosesionnsuresosnsteseeesoens 6 1 1 Message to the USer ccceccccsccsscsesecsseesecesecseecseecaeeeseeeneeeeeeesseensecaaecsaecsaecaaecaeecaeecaeeeseeeeeeeeeeerenes 6 1 2 Usmgthi Mantal csser esris eirs onies naiss aai nii 6 1 3 Conventions Used in This Manual 0 ce ceeeecsesesseceeeseceeveeceaeeeceaeceeeeecaesaecnaveeeeaeeeeeaesaeeeeeneeaeed 7 1 4 Warning Regarding Medical Use s essesessseeeesseseessesersssseeessstsetssesetstsstenessreressesesstsressesesesseese T l5 Warranty kossisssesmiii ere iiri e er E EE EENE EEE BEKEA EEEE EEEE EEEE ER 7 1 6 Warranty and Repair Return Procedure Assistance and Support eseeeeeseeeerersererersrsrrerererser 7 L7 System Req ifements ssssssssi irisse snenia ie ianea aranna tgs Dov EEN EEEE EEEE EEA E aE EERE 7 2 PROGRAMMING ENVIRONMENTS amp GETTING STARTED osssssesseses
92. ich 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 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 7 1 Compiling This file can be compiled as is within the GetStartedVxW 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 debug flags D_VXWORKS D_ACQIRIS are present 2 7 2 Loading First download the Low Level kernel mode VxWorks Device Driver file VxWorksDriverPCI out to the target machine followed by the VxWorks Digitizer Driver file AcqirisVxWUMode out Finally you should download the VxWorks application GetStarted VxW out Programmer s Guide Page 15 of 100 acqiris 2 7 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 8 Linux The AcqirisDemo program can simply be run from the AcqirisLinux directory by entering Demo AcqirisDemo The library usr lib libAnDBSLib a is compiled with
93. igitizers ensures that there is no further activity that could for example generate an interrupt The function AcqrsD1_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 AcqrsD1_ 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 AcqrsD1_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 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 digitizer 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 AN 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
94. ime of the function AcqrsD1_configHorizontal is replaced by StartDelay and StopDelay in future software versions the parameter samplnterval 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 it 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_getAvgConfig 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 aver
95. ime 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 for digitizer readout as a function of the number of segments number of samples CPU speed and the operating system 5 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 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 sho
96. imes 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 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 8 7 Reading AP101 AP201 Analyzer Waveforms 3 8 7 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 Programmer s Guide Page 40 of 100 acqiris 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 4 000 000 Before reading the buffered data you
97. ional API equivalent AcgqrsD1_configAvgConfig id channel TdcHistogramIncrement amp style Discussion 1 means increment by 1 2 means increment by the ADCvalue NoiseBase equivalent Programmer s Guide Page 70 of 100 acqiris chAxTDCHistoMinTOT Purpose Controls the desired minimum width of a peak in the waveform Prefixes Access Type Values channel RW integer 1 2 3 or 4 Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcqrsD1_configAvgConfig id channel TdcMinTOT amp width Discussion A peak is accepted if there are at least n consecutive data samples above the Threshold For SimpleTDC mode ONLY chAxThreshold Purpose Value in Volts of the threshold for Noise Supressed Averaging Prefixes Access Type Values channel RW double In Volts Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcqrsD1_configAvgConfig id channel Threshold amp thresh Discussion Programmer s Guide Page 71 of 100 acqiris chAxThresholdEnable Purpose Control whether the threshold test will be applied to the data of the channel before accumulation Prefixes Access Type Values channel RW string OLEY or TOn Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcgqrsD1_configAvgConfig id channel ThresholdEnable
98. iris recommends to use the general purpose read function AcqrsD1_readData rather than the legacy function AcqrsD1_readRealWform 3 8 4 1 Averaged Waveforms in Volts You should use the general purpose function AcqrsD1_readData or the legacy function AcqrsD1_readRealWform 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 Programmer s Guide Page 37 of 100 acqiris 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 readParams nbrSegments 1 readParams firstSampleInSeg 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
99. 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 13 ASBus Operation The ASBus is intended to synchronize a number of similar 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_multiInstrAutoDefine or AcqrsD1_multilnstrDefine each combined instrument can be controlled when using its instrumentID with the same functions as single digitizers Acqiris recommends the use of the automatic function unless you need special control over the order in which the digitizers are numbered within the Multilnstrument 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 The automatic function always assigns the clock master role to a module with the
100. isDxRoot gt MATLAB or copy all of the files from that directory to the directory of your choice 2 5 1 1 Single Acquisition Filename Aq_SingleAcquisition m Argument No Argument This first example shows you how to perform a single acquisition The desired setup file is loaded You then create your AnalogInput object start the acquisition and then get and plot the acquired data 2 5 1 2 Multiple Acquisition Filename Aq_MultipleAcquisition m Argument No Argument In this m file the main difference with the Single Acquisition example is that we put the acquisition sequence into a loop In that way you can manage multiple acquisitions and store data in the MATLAB Workspace 2 5 1 3 Mode Live Filename Aq_ModeLive m Argument InstrumentID Default 0 Use gt gt Aq ModeLive Select default digitizer ID 0 gt gt Aq ModeLive 2 Select digitizer with InstrumentID 2 This MATLAB program displays your signal in a live mode Programmer s Guide Page 11 of 100 acqiris An Instrument Settings module that can be used during acquisition has been added There is also a menu that gives the possibility to load an existing setup file or to save to a new setup file You can modify the function applied to the selected channel You should look for the function named ProcessFen and modify it You can also add arguments if necessary 2 5 2 Setup and Settings 2 5 2 1 Manipulating Attributes In the example c
101. les 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 10 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 Programmer s Guide Page 46 of 100 acqiris 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 particularly important for persistence displays or highly zoomed random interleaved displays as generated from overlaid segments where a single waveform or wavefo
102. lls Programmer s Guide Page 56 of 100 acqiris Double delayOffset delayScale AcqrsD1_ getInstrumentiInfo ID DelayOffset amp delayOffset AcqrsD1_getInstrumentiInfo ID DelayScale amp delayScale The functions AcqrsD1_getInstrumentInfo should be called just before the start of the acquisition i e before calling AcqrsD1_acquire but after all AcqrsD1_config functions 3 15 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 AcqrsD1_InitWithOptions resourceName false false CAL FALSE amp instrumentID 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 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
103. lly 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 MultiInstrument 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 13 ASBus Operation 3 2 7 AqGeo map file positioning For ASBus MultiInstruments in some systems the driver will need additional information about 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 AgDrv4 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 Programmer s Guide Page 21 of 100
104. lows 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 instrumentID To allow the second acquisition to start as soon as possible a call to AcqrsD1_processData instrumentID processType 1 follows immediately After this start up procedure 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 100 acqiris 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 pa disabled int acq Bank 1 x i int ProcessingO int Processing readout y AutoSwitch S Description Software implementation 0 The software configures the mode the acquisition parameters and the readout 1 The software starts the first acquisition 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 A
105. ly 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 or 98 Ovhdpy has been observed to be 20 lower Programmer s Guide Page 97 of 100 acqiris 3 The circular buffer analysis overhead time Ovhdpuffer is 2 500 us Pentium CPU speed in MHz Thus for a 250 MHz Pentium Ovhdpyge is 10 us and for a 500 MHz Pentium 5 ys 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
106. me horPos Note delayTime horPos lt delayTime by definition e Jn 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 11 Sequence Timestamps 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 Acqiris digitizers feature a timestamp in order to measure the time between the triggers of consecutive segments 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 functions AcqrsD1_readCharWform and AcqrsD1_readRealWform return the timestamp value as 2 32 bit values In order to do time differences you
107. must switch to the other memory bank Typically 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 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 instrumentID 3 0 memoryBank AcqrsD1_acquire instrumentID essential AcgrsD1 readData instrumentID channel amp readParams waveformArray amp dataDesc amp segDesc The returned data array contains the ac
108. n The In AddSub choices allow the control of real time add subtract functionality for either or both of the channels The In AvgrStartVetoEnable configures the signal as a trigger enable If P1Signal and or P2 Signal are enabled for the Add Subtract mode then the data will be added if the signal or the or of both signals is in the high state The same rule holds if they are used for trigger enable The Out Average signal goes high after the first trigger is accepted for an average and drops back down when the last trigger s acquition is complete Programmer s Guide Page 63 of 100 acqiris axP2Signal Purpose Define how the P2 Control signal should be used Prefixes Access Type Values RW string Disabled In AddSubChi In AddSubCh2 In AddSubCh1ich2 In AvgrTrigEnable In AvgrStartVetoEnable Out Average Models AP235 and AP240 with Averager option Traditional API equivalent AcqrsD1_configAvgConfig id channel P2Control amp function Discussion The In AddSub choices allow the control of real time add subtract functionality for either or both of the channels The In Average configures the signal as a trigger enable If P1Signal and or P2 Signal are enabled for the Add Subtract mode then the data will be added if the signal or the or of both signals is in the high state The same rule holds if they are used for trigger enable The Out Average signal
109. n of raw ADC values to volts or other user units Prefixes Access Type Values channel RW double Models ALL Traditional API equivalent NONE Discussion See the MATLAB discussion in the Programmer s Guide section 2 5 or section 6 2 4 of the SP201 Manual chScaleOffset Programmer s Guide Purpose Functions as an additive constant for the conversion of raw ADC values to volts or other user units Prefixes Access Type Values channel RW double Models ALL Traditional API equivalent NONE Discussion See the MATLAB discussion in the Programmer s Guide section 2 5 or section 6 2 4 of the SP201 Manual Page 77 of 100 acqiris chTime2ndOffset Purpose Functions as an additive constant to adjust the time of the data points of an acquisition Prefixes Access Type Values RW double In seconds Models ALL Traditional API equivalent NONE Discussion See the MATLAB discussion in the Programmer s Guide section 2 5 or section 6 2 4 of the SP201 Manual chTime3rdOffset Programmer s Guide Purpose Functions as an additive constant to adjust the time of the data points of an acquisition Prefixes Access Type Values RW double In seconds Models ALL Traditional API equivalent NONE Discussion See the MATLAB discussion in the Programmer s Guide section 2 5 or section 6 2 4 of the SP201 Manual Page
110. nal trigger Prefixes Access Type Values channel amp ext RW string TAC DE Models ALL Traditional API equivalent AcqrsD1_configVertical id coupling AcqrsD1 getVertical id amp coupling Discussion The chCoupling is only part of the coupling of the old API chImpedance is also needed chFullScale Purpose Control the full scale of a channel Prefixes Access Type Values channel amp ext RW double discrete In V Models ALL Traditional API equivalent AcqrsD1 configVertical id channel fullScale AcqrsD1_ getVertical id channel amp fullScale Discussion For a channel the gain LSB is the full scale divided by the number of bits in the output data representation This is not always the same as the ADC gain that is calculated using the actual number of bits of the ADC For an external trigger this attribute is used to control the full scale range of the allowed trigger level Studying the current range of the attribute may be needed to understand all of the possible values Programmer s Guide Page 74 of 100 acqiris chImpedance Purpose Control the input impedance of a channel Prefixes Access Type Values channel amp ext RW string 50 1M Gnd Models ALL Traditional API equivalent AcqrsD1_ configVertical id coupling AcqrsD1_ getVertical id amp coupling Discussion Studying the current range of
111. ndicates whether the range of values will be described as discrete or not If the range is discrete the allowed values will be enumerated explicitly otherwise the full range will be described as a collection of triplets low value high value increment In the case where the increment is non zero a triplet defines allowed values of the attribute as follows low value low value increment low value 2 increment high value If the increment is 0 all values between the low and high values are allowed 4 1 Attribute dependencies and coerced values Changing certain attribute values can affect the ranges of other attributes This can cause the value of the dependent attribute to change For example changing the chFullScale of a channel can change the ranges for chOffset and trThres1 Similarly requested attribute values will not always be available In order to verify that all changes are consistent with your expectations you can always check final attribute values with the GetAttributeValue method Programmer s Guide Page 58 of 100 4 2 Functional grouping of attributes Channel vertical settings chAttenuation chFullScale chOffset chScaleOffset Horizontal timebase settings chTime2ndOffset ckDelay extCkRatio extSparsing samplingIntv trDelay Trigger settings chBandwidthLimit trCoupling trSlope TrThres2 trTVLine Control IO settings ctrIOASignal ctrlLOPxiStar Others channelEnable convertersPerChan
112. ndow 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 2 5 MATLAB MATLAB is a very powerful environment to analyse and display data The MathWorks Inc have developed a Data Acquisition Toolbox that can acquire data from digitizer cards The Acqiris Adaptor exchanges messages between the MATLAB Engine and the Acqiris instrument driver The Acqiris Adaptor lets you acquire data directly from the hardware without additional software It offers the possibility to start and stop the acquisition as well as to get data Windows based modules and command line shortcuts are used to configure the instruments 2 5 1 Examples These examples are in the directory lt AcqirisDxRoot gt MATLAB When you execute these examples either set the MATLAB current directory cd Command to lt Acqir
113. ne executing a single command Only one process on a machine can have loaded the Acqiris driver at any given moment Most of the AcqrsD1 driver functions are reentrant After initialization they are protected against multiple calls from different threads The unprotected routines are AcqirisD1_init AcqirisD1_initWithOptions AcqirisD1_getNbrPhysicalInstruments AcqirisD1_ closeAll AcqirisD1_multiInstrAutoDefine AcqirisD1_multilnstrDefine AcqirisD1_multiInstrUndefineAll Be sure to read the comments in the header file AcqirisD1Interface h or AcqrsD1Interface bas or the function parameter discussions in chapter 2 DEVICE DRIVER FUNCTION REFERENCE of the Programmer s Reference Manual The examples below do not check the return value of the AcqrsD1_ 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 AcqrsD1_InitWithOptions For real devices you can also use the slightly simpler function AcqrsD1_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 t
114. not destroy the originally acquired data 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 APXO1 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 6 Loop to 4 above You need to implement a method to interrupt the infinite loop whenever required However you should make sure that you
115. nt is the 5th segment followed by the 6 7 8 1 etc The youngest useful segment is the 3 one while the 4 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 15 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 15 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 ca
116. odel 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 First the desired files 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 AgDrv4 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 Additional Phar Lap ETS VxWorks Instructions For ETS and 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 procedure is also shown in the GetStartedETS cpp ETS sample program and the GetStarted cpp VxWorks sample program Thus AcqrsD1_InitWithOptions has to be called with ViString options cal 0 status AcgrsD1_ 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 AcqrsD1_configLogi
117. ogrammer s Guide Page 89 of 100 timeWindow Purpose acqiris Control the total time spanned by a segment in an acquisition Prefixes Access Type Values RW double In seconds Models ALL Traditional API equivalent NONE Discussion timeWindow samples samplingIntv trClass Purpose Control the type of trigger Prefixes Access Type Values RW string Edge TV Models ALL Traditional API equivalent AcqrsD1_ configTrigClass id trigClass AcqrsD1_getTrigClass id Discussion amp trigClass Studying the current range of the attribute may be needed to understand the current range Programmer s Guide Page 90 of 100 acqiris trCoupling Purpose Control the trigger coupling of a trigger source signal Prefixes Access Type Values channel RW string Dc AC HFRej Models ALL Traditional API equivalent AcqrsD1_ configTrigSource id channel trigCoupling AcqrsD1_ getTrigSource id channel amp trigCoupling Discussion This attribute controls the coupling of the trigger source signal to the trigger discriminator Studying the current range of the attribute may be needed to understand the current range trDelay Purpose Control the pre or post trigger delay time for an acquisition Prefixes Access Type Values RW double In seconds Models ALL Traditional API equivalent Acqrs
118. ol whether the trigger out signal should be generated only for accepted triggers or for all of them Prefixes Access Type Values RW string Off or On Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcgqrsD1_configAvgConfig id channel TrigAlways amp always Discussion Programmer s Guide Page 67 of 100 axTrigResync Purpose acqiris Controls whether the trigger should be used to resynchronize the sampling clock Prefixes Access Type Values RW string NoResync Resync or FreeRun Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcgqrsD1_configAvgConfig id channel TrigResync amp sync Discussion The TrigResync values NoResync and Resync require a valid trigger while FreeRun requires no trigger useful for background acquisition chAxInvertData Purpose Indicate whether the data of the channel should be inverted Prefixes Access Type Values channel RW string OLE or On Models AP235 and AP240 with Averager option AP100 AP200 Traditional API equivalent AcgqrsD1_configAvgConfig id channel InvertData amp invert Discussion If the data is inverted the most significant bit of the raw data will be flipped the threshold will select data values with voltages below the desired value Programmer s Guide Page 68 of 10
119. output data an array of segment descriptors AqSegmentDescriptor and a waveform descriptor AqDataDescriptor 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 Programmer s Guide Page 34 of 100 acqiris static long nbrSegments 1 readMode 0 requires this value long nbrPoints 1000 char dataArray nbrPoints 32 AqReadParameters readPar new AqReadParameters AqDataDescriptor dataDesc new AqDataDescriptor AqSegmentDescriptor segDesc new AqSegmentDescriptor nbrSegments 0 0 byte readPar gt readMode 0 0 standard waveform readPar gt dataType 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 0 0 status AcqrsDl readData instrumentiID 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
120. ply a change in the value in volts set for the trThres1 2 levels trT VField Purpose Control the field choice for the TV trigger Prefixes Access Type Values ext RW string Odd Even Models 12 bit FAMILY Traditional API equivalent AcqrsD1 configTrigTV id channel field AcqrsD1_ getTrigTV id channel amp field Discussion Studying the current range of the attribute may be needed to understand all of the possible values Programmer s Guide Page 95 of 100 acqiris trTVLine Purpose Control the line choice for the TV trigger Prefixes Access Type Values ext RW long Models 12 bit FAMILY Traditional API equivalent AcqrsD1_ configTrigTV id channel line AcqrsD1_ getTrigTV id channel amp line Discussion Studying the current range of the attribute may be needed to understand all of the possible values trT VStd Purpose Control the standard to be used for the TV trigger Prefixes Access Type Values ext RW string 650 50Hz 525 60Hz Models 12 bit FAMILY Traditional API equivalent AcqrsD1 configTrigTV id channel standard AcqrsD1 getTrigTV id channel amp standard Discussion Studying the current range of the attribute may be needed to understand all of the possible values Programmer s Guide Page 96 of 100 acqiris 5 Appendix A Estimating Data Transfer Times The t
121. pplied 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_configControllO with the parameters connector 1 I O A or 2 I O B and signal 9 The function AcqrsD1_configFCounter sets the parameters specific to the frequency measurements AcqrsD1_ configFCounter instrumentID channel type targetValue apertureTime 0 0 0 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 Programmer s Guide Page 54 of 100 acqiris 1 Period if targetValue is larger th
122. quired waveforms 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 8 7 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 Programmer s Guide Page 41 of 100 acqiris const int NbrGates 64 long channelNbr 0 long configObj AvgGate long lastGate NbrGates AqGateParameters gatePara NbrGates for int i 0 i lt NbrGates itt gatePara i GateLength 256 gatePara i GatePos i gatePara i GateLength AcqrsD1_configSetupArray instrumentID channelNbr configObj gatePara lastGate 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 const int NbrGates 64 long channelNbr 0 long configObj AvgGate long lastGate AqGateParameters gatePara NbrGates AcqrsD1_getSetupArray instrumentID channelNbr configObj gatePara amp lastGate Make sure to use a pointer to the last argumen
123. quisition instrumentID timeout Read out data etc before calling again AcqrsD1_ acquire Note that the function AcqrsD1_acquire is still needed However it behaves somewhat differently in that is does not start data recording 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 Start on Trigger mode is not operational for the 12 bit digitizers 3 14 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 Programmer s Guide Page 55 of 100 acqiris 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 occurrenc
124. r reasons of data alignment acquisition stop time overhead and other reasons In some cases the additional invisible samples can exceed the number 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 section 3 9 Trigger Delay and Horizontal Waveform Position for 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 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 23 of 100 acqiris 3 4 Configuring Averagers 3 4 1 Basic configuration The averagers have 2 operational modes digitizer and averager controlle
125. rSamplesNom 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 ID nbrSamplesNom amp nbrSegments You have to make sure that you ask for this information after the acquisition configuration has been established Similarly for dataType 3 the amount of memory needed in bytes is arraySize gt 8 segmentOffset nbrSegments 1 and with the other two conditions as above The following code can be used for reading a waveform sequence in 8 bit representation 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 0 0 byte readPar gt readMode 1 1 sequence waveform readPar gt dataType 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 Ne O O readPar gt reserved3 e status AcqrsDl getInstrumentinfo ID TbSegmentPad amp currentSegmentPad in this case the next call doesn t have any surprises status AcqrsD1_ g
126. rage 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 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 performance 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 10 Horizontal Parameters in Acquired Waveforms is not taken into account 3 8 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 Acq
127. ration modules The horizontal control parameters 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 sFmax vs nbrConvertersPerChannel 1 2 4 DC135 Y x inputFrequency x inputFrequency DC140 Y x inputFrequency 2 x inputFrequency DC211 DC211A 2 x inputFrequency DC241 DC241A 1 x inputFrequency 2 x inputFrequency DC271 DC271A 2 x inputFrequency 1 x inputFrequency 2 x inputFrequency DC440 DC438 1 x inputFrequency DP310 DP308 DC436 DP306 4 x inputFrequency DP214 1 x inputFrequency DP235 AP235 x inputFrequency 1
128. raw data readout you should set long channel 1 gate 0 AcqrsD1_configAvgConfig instrumentID channel GateType amp gate For user gate readout you have to define the groups of data samples that you want to read for each segment If needed new values 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 instrumentID 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 Programmer s Guide Page 28 of 100 acqiris 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 AcqrsD1_configSetupArray InstrumentID 0 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
129. rawData sample 1 or 2 depending on the instrument vO ffset chOffset The original Time vector starts at 0 and increases in steps of 1 SampleRate The last line above shows the horPos and trDelay corrections to the Time vector so that the time of the trigger is 0 For segmented acquisition we decided to concatenate all segments in the same vector returned by the method getData For multichannel instruments the getData method returns a vector for each channel activated So if you have chosen to acquire on n channels m segments of p samples you will get a matrix with size m p n Using MATLAB commands you can easily extract only one segment from the matrix For example if you would like to extract the segment j on the channel k you can write gt gt vectorSeg DataAcquired j 1 p 1 3 p K The Time vector shown in the simple case above is not appropriate because the adaptor has no information about horPos correction and t0 value Note that t0 value is different for each channel and horPos is different for each segment So if you want to access information for segment j on channel k gt gt set AI channel k segmentDescriIndex j gt gt horPos get AI channel k horPos gt gt timeStampLo get AI channel k timeStampLo gt gt timeStampHi get AI channel k timeStampHi Similarly for the t0 value gt gt t0 get AI channel k t0 where t0 trDelay chTimeOffset chTime2ndOffset chTime3rd
130. rm 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 Yai Origin samplnterval First data point N horPos Trigger hOffset delayTime nbrSamples 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 delay Time e The first data point of the waveform is defined as the ast acquired data point before the time origin It is indexed with i 0 in the formula below 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 delayTi
131. rt 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 AcqrsD1_readData for readMode 0 T M Ovhdpy M N Xfr e AcqrsD1_readData for readMode 1 T Ovhd pu M OVA e 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 us typically 0 01 Ovhd pua DMA overhead time per segment in us Ovhd pf 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 X 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 Xp 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 Ovhdpyy is approximate
132. rumentID channel segmentNumber 0 nbrSamples waveformArray amp returnedSamples amp horPos amp sampTime amp tStampLo amp tStampHi 3 8 4 2 Averaged Waveforms as 32 bit Sums You must use the general purpose function AcqrsD1_readData Programmer s Guide Page 38 of 100 acqiris 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 firstSampleInSeg 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 AcqrsD1_readData instrumentID 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 8 5 Reading a RT Add Subtract Averaged Waveform from an Averager
133. s 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 8 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 8 1 Reading Digitizer Waveforms with the Universal Read Function should be used with readMode 2 For reading data from analyzers please refer to 3 8 6 Reading SSR Analyzer Waveforms or 3 8 7 Reading AP101 AP201 Analyzer Waveforms 3 8 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
134. should transform them into a 64 bit integer e In Visual C C use the 64 integer __int64 as follows Programmer s Guide Page 47 of 100 acqiris __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 Abs tStampLo Else 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
135. t 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 2 13 an application that enables basic operation of Acgiris digitizers or averagers in a Windows 95 98 2000 NT4 XP environment the operation of AP_SSRDemo and in the following chapter APx01Demo applications that enable basic operation of Acqiris analyzers in a Windows 95 98 2000 NT4 XP environment This Programmer s Guide is divided into 4 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 DIGITIZER provides information on using the device driver functions to operate an Acqiris digitizer Chapter 4 ATTRIBUTES contains reference information about attributes The attribute interface to the driver can
136. t since it returns the number of gates astGate 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 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 AcqrsD1_readData instrumentID 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 X GateLength nbrSegments Programmer s Guide Page 42 of 100 acqiris Note If for each gate the sum GatePos GateLength exceeds the nbrSamplesInSeg GatePos is reduced to satisfy GatePos GateLength
137. the attribute may be needed to understand all of the possible values chInput Purpose Control the choice of input BNC for some single channel units Prefixes Access Type Values channel RW string AY cor TB Models DP111 DP211 Traditional API equivalent AcqrsD1_ configMultInput id channel input AcqrsD1_ getMultInput id channel amp input Discussion This command is only of interest for single channel units allowing the choice of A or B inputs Programmer s Guide Page 75 of 100 acqiris chOffset Purpose Control the DC offset of a channel Prefixes Access Type Values channel RW double In V Models ALL Traditional API equivalent AcqrsD1_ configVertical id channel offset AcqrsD1_ getVertical id channel amp offset Discussion The mid range ADC value corresponds to the offset This is the opposite of the convention in the traditional API chScale2ndFactor Purpose Functions as an additional multiplier for the conversion of raw ADC values to volts or other user units Prefixes Access Type Values channel RW double Models ALL Traditional API equivalent NONE Discussion See the MATLAB discussion in the Programmer s Guide section 2 5 or section 6 2 4 of the SP201 Manual Programmer s Guide Page 76 of 100 acqiris chScaleFactor Purpose Functions as an additional multiplier for the conversio
138. to nbrSegments 1 Specifying more than segment in AcqrsD1_configMemory implies the use of Sequence mode The 5 main configuration functions 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 On current 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 trigger 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 fo
139. to the driver can be used with AcqirisMAQS the MATLAB interface and the SP201 Software Development Kit This section of the manual will give details on all of the available attributes The full name of an attribute is often composed of a prefix before the name of the simple attribute itself In other words full_attribute_name lt prefix gt attribute prefix channel prefix external prefix channel prefix ch1 ch2 ch3 ch4 ch5 a chnn where nn is the last channel number of the instrument external prefix ext1l ext2 extm where m is the last external trigger channel of the instrument The number of channels can be found from the channels keyword of the instrument identity Similarly the number of external triggers can be found from the confExtTr keyword Examples Full scale for channel 2 lt ch2 gt chFullScale Number of samples samples External trigger slope for single module noASBUs lt extl gt trSlope Attributes can either be modifiable or read only This is shown by the Access characteristic that is either RW read write or RO read only respectively Only the RW client of an instrument can actually write modify an RW attribute The type of an attribute shows what kind of value will be employed when an attribute is queried or modified Although the argument is always a string the string will be a representation of an integer a double precision real or a string It also i
140. uide Page 4 of 100 acqiris ChCoupliNGsss A Balin Bahia AN ance lata esa eel RNG ne leer estes 74 CHF US Cale E A E E E caboose E st castasaucvessiecvatectecueeseays 74 CMS Cal C2NG AGEL Ss casccessscvesstscesvivsxentxeue E E O EO EES 76 CHS CBCP ACORN E T A A E EE E acedseisecsaena ssa cagenace ASCOSE henee a TA ENE ENRE NEE EE E chTime2ndOffset chTime3rdOffset CI TAMEOTSE E E E E E E E Col ol I ane ee revere E E E ER E A AE A A ENS OAT EDA NENAS NOE EN EEEN A OEN OE N ON EAN EN ckThreshLvl CT Gis cases isd Sen E coed Seale dates ic E E S E doe tod E AE N Aida road saa ec aout ee aceaep teats convertersPerChan CHITOAS 1 Sal APEN OEE T N EE CHMOBSigtial EEEE EEE E E EE EEEE ott TOPXHRefILOMHZ sacdan da dese bassdcecdis ded eaS LEEA ELENE eE E O EAEEREN 83 AOPA ISTAE e aa TE AATE AET AEEA O AET EOE EAS 83 ctt OTrOutLeyel nencen ssia e E EEE EEEE NEEESE REES NTON 84 CHITOTPOUPRES YING oiiaii sia E EE EE te ee de ose AA ST A T E E 84 OX ECKR AIO sess alse sisus casts EEE PAE AEE A E E EE E E AE I E A E E E E E 85 XMMP reg eoster aa a a aE eaa E ERE aE saeara ara E ESE 85 EXCSAMP MGR ALS ss fcaneds svete consnsds succeeded edions eika Eoee sede bo ESETRE ran svieocapeds sxednede Gasaness ouddbdsdacanateasutgoasdoeinedhseis 86 EXAS PALS 6 55 seiirt ledapiveceedsceedessnsesdte s toadesspavatenss eea eE Sataa Ee SEa are ETE O soales suse cganasssuayctewlsdendesanseedeesn sata 86 TENE E E es cet EE a E ex eee cee cats etc eee eee E ne
141. uisition does not stop immediately since the digitizer may continue 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 AegqrsDl forcerrig instrumentiD if AcgrsD1l_ waitForEndOfAcquisition instrumentID timeOut ACQIRI S_ERROR ACO T IMEOUT AcqrsD1_stopAcquisition instrumentID 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 7 5 Analyzer Autoswitch mode The AP Analyzers implement an autoswitch mode that al
142. variable external clock This 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 Programmer s Guide Page 50 of 100 acqiris the external clock signal through the user defined threshold Thus the sampling rate is equal to the input frequency There is no concept of trigger for this mode and 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 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_w
143. vel for External clock or Reference operation Prefixes Access Type Values RW double Models ALL Traditional API equivalent AcqrsD1 configExtClock id inputThreshold AcqrsD1 getExtClock id amp inputThreshold Discussion See section 3 11 of the Programmer s Reference manual Programmer s Guide Page 80 of 100 acqiris ckType Purpose Control the type of External clock or Reference operation Prefixes Access Type Values RW string Internal ExtCkContinuous ExtRef1l0MHz ExtCkStartStop Models ALL Traditional API equivalent AcqrsD1_configExtClock id clockType AcqrsD1_ getExtClock id amp clockType Discussion See section 3 11 External Clock and Reference of the Programmer s Reference manual convertersPerChan Purpose Returns the number of ADC converters used for each channel Prefixes Access Type Values RO integer 1 2 4 Models DC135 DC140 DC241 DC241A DC271 DC271A DP235 DP240 AP235 AP240 Traditional API equivalent AcqrsD1_ getChannelCombination id amp nbrConvertersPerChannel Discussion Use input to control both this number and the choice of active channels Programmer s Guide Page 81 of 100 acqiris ctrILOASignal Purpose Control the functionality of the CtrlI O A connector Prefixes Access Type Values RW string

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