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DM7420 Data Acquisition Driver for Windows 95/98/NT User`s Manual

1. Description Remove all samples from the High Speed Digital Input FIFO NOTE Reading from an empty FIFO e g with ReadDinFifo7420 results in undeterministic data Parameters hBoard device handle ClearDIO7420 Syntax void ClearDI07420 RTDHANDLE hBoard Description Reset the Digital I O chip It programs all UO lines for input and programs the Advanced Digital Trigger for Event Mode NOTE It does not clear a pending interrupt You must make a call to ClearDIO0IrqStatus7420 explicitly Parameters hBoard device handle ClearDIOOIrqStatus7420 Syntax void ClearDIOO0OIrgStatus7420 RTDHANDLE hBoard Description Clears the Digital IRQ status flag You must acknowledge Digital Interrupts by calling this function Failing to do this no more Digital Interrupts will be generated by the Digital I O chip Parameters hBoard device handle See Also Advanced Digital Trigger 28 90 DM7420 Data Acquisition Driver for Windows 95 98 NT ClearlTMask7420 Syntax void ClearITMask7420 RTDHANDLE hBoard uint16 mask Description Acknowledge interrupts from the specified interrupt sources NOTE Usually there is no need to call this function because it is automatically called when you install an interrupt handler However if you do not install a handler for an interrupt source but interrupts are enabled from that source see SetITMask7420 you may need this function to acknowledge in
2. NOTE For lines programmed for output the current value of the line is returned Parameters hBoard device handle Return Value 8 bit port value bit mask ReadDIO17420 Syntax uint8 ReadDIO17420 RTDHANDLE hBoard Description Read Port I digital input lines Parameters hBoard device handle Return Value 8 bit port value ReadITOverrun7420 Syntax uintl6 ReadITOverrun7420 RTDHANDLE hBoard Description Read the Interrupt Overrun Register Parameters hBoard device handle Return Value Returns a mask of IT sources which have been overrun Bit 0 0x0001 ADC FIFO Write Bit 1 0x0002 Reset CGT Bit 2 0x0004 reserved Bit 3 0x0008 Pause CGT 56 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Bit 4 0x0010 ADC FIFO half full Bit 5 0x0020 ADC FIFO full Bit 6 0x0040 ADC Sample Counter Bit 7 0x0080 Not used Bit 8 0x0100 Not used Bit 9 0x0200 User TC1 out Bit 10 0x0400 User TC1 out inverted Bit 11 0x0800 User TC2 out Bit 12 0x1000 Digital Interrupt Bit 13 0x2000 External Interrupt Bit 14 0x4000 External Trigger rising edge Bit 15 0x8000 External Trigger falling edge See Also ClearI TOverrun7420 ReadTimerCounter7420 Syntax void ReadTimerCounter7420 RTDHANDLE hBoard int counter uint8 mode uintl6 count Description Read back programmed operation mode and current counter value of a 8254 Timer Counter Parameters hBoard device
3. Description Read port 0 compare mode Parameters hBoard device handle 36 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Return Value 0 Event Mode 1 Match Mode GetDIOOCompareValue7420 Syntax uint8 GetDIOO0CompareValue7420 RTDHANDLE hBoard Description Read pattern of Port 0 I O lines for Digital Interrupt generation Parameters hBoard device handle Return Value pattern GetDIOODirection7420 Syntax uint8 GetDIOODirection7420 RTDHANDLE hBoard Description Return programmed Digital I O Port 0 line directions Parameters hBoard device handle Return Value 8 bit direction mask Bit 0 line is programmed for input Bit I line is programmed for output GetDIOOMask7420 Syntax uint8 GetDIOOMask7420 RTDHANDLE hBoard Description Return Digital Interrupt mask for Port 0 I O lines Parameters hBoard device handle Return Value 8 bit interrupt mask Bit 0 line is disabled to take part in Digital Interrupt generation Bit I line is enabled to take part in Digital Interrupt generation DM7420 Data Acquisition Driver for Windows 95 98 NT 37 90 See Also Advanced Digital Trigger GetDIO1 Direction7420 Syntax uint8 GetDIOlDirection7420 RTDHANDLE hBoard Description Return Digital I O Port 1 direction Parameters hBoard device handle Return Value Bit 0 port direction 0 input 1 output Bit 1 7 0 GetDIOStatus7420 Syntax
4. Enable generating interrupt when Channel Gain Table execution resets to the beginning of the table IRQM CGT PAUSE 0x0008 Enable generating interrupt when a Channel Gain Table entry has its Pause Bit set and CGT Pause is enabled see EnableCGTPause7420 IRQM ADC ABOUT CNT 0x0010 Enable generating interrupt when About Counter counts down to zero and About Counter Stop is enabled see EnableAcntStop7420 IRQM ADC DELAY CNT 0x0020 Enable generating interrupt when Delay Counter counts down to zero IRQM ADC SCNT 0x0040 DM7420 Data Acquisition Driver for Windows 95 98 NT Enable generating interrupt when A D Sample Counter counts down to zero IRQM UTC1 0x0200 Enable generating interrupt on User TC1 ticks IRQM UTC1 INV 0x0400 Enable generating interrupt when User TC1 out goes low IRQM_UTC2 0x0800 User TC2 out Enable generating interrupt on User TC2 ticks IRQM_DIGITAL_IT 0x1000 Enable generating interrupt when a Digital Interrupt occurs IRQM EXTERNAL IT 0x2000 Enable generating interrupt on the External Interrupt pin Interrupt will be generated on the rising or falling edge depending on the programmed External Interrupt polarity see SetEIntPolarity 7420 IRQM ETRIG RISING 0x4000 IRQM ETRIG FALLING 0x8000 Enable generating interrupt on External Trigger rising falling edge See Also Interrupts InstallCallbackIrqHandler7420 SetPacerClock7420 Syntax void SetPacerClock7420
5. Mask mode Returns the programmed value of the Compare Register see GetDIOOCompareValue7420 Returns the programmed Advanced Digital Trigger clock see GetDIOO0Clock7420 0 8 MHz On board Oscillator 1 User TC Counter 1 Returns the Digital I O Port 0 IRQ Status see GetDIOOStatus7420 0 no IRQ 1 IRQ return value DM7420 Data Acquisition Driver for Windows 95 98 NT 53 90 54 90 DM7420 Data Acquisition Driver for Windows 95 98 NT ReadADData7420 Syntax int ReadADData7420 RTDHANDLE hBoard Description Read sample 12 bit from the A D FIFO Parameters hBoard device handle Return Value Signed 12 bit A D Data See Also ReadADDataWithMarker7420 ReadADDataWithMarker7420 Syntax intl6 ReadADDataWithMarker7420 RTDHANDLE hBoard Description Read A D FIFO data and data marker bits Parameters hBoard device handle Return Value Signed 12 bit AD Data and 3 bit Data Marker See Also ReadADData7420 ReadDinFifo7420 Syntax uintl6 ReadDinFifo7420 RTDHANDLE hBoard Description Read a block of samples from the High Speed Digital Input FIFO NOTE You must ensure that the FIFO contains at least nSamples samples Parameters hBoard device handle DM7420 Data Acquisition Driver for Windows 95 98 NT 55 90 See Also ReadDinFifoBlock7420 ReadD1007420 Syntax uint8 ReadDIO17420 RTDHANDLE hBoard Description Read Digital I O Port 0 digital input lines
6. counter One of the 16 bit timer counters of the board Use TC XXXX for argument counter Get8254Status7420 Syntax uint8 Get8254Status7420 RTDHANDLE hBoard int counter Description Read status of a 8254 Timer Counter Parameters hBoard device handle counter One of the 16 bit timer counters of the board Use TC XXXX for argument counter GetAutolncDataByte7420 Syntax unsigned GetAutoincDataByte7420 RTDHANDLE hBoard AutoincSetup autoincsetup uintl6 DataNum DM7420 Data Acquisition Driver for Windows 95 98 NT 35 90 Description This routine is used to read a block of samples from the A D FIFO Parameters hBoard device handle autoincsetup parameters for auto increment command DataNum number of data item to read GetAutolncDataWord7420 Syntax unsigned GetAutoIncDataWord7420 RTDHANDLE hBoard AutoincSetup autoincsetup uintl6 DataNum Description This routine is used to get the data with auto increment driver mode Parameters hBoard device handle autoincsetup parameters for auto increment command DataNum number of data item to read GetDIOO0Clock7420 Syntax uint8 GetDIOOClock7420 RTDHANDLE hBoard Description Read Clock set for the bit programmable Digital I O port 0 Parameters hBoard device handle Return Value 0 8 MHz On board Oscillator 1 User TC Counter 1 GetDI00CompareMode7420 Syntax uint8 GetDIOO0CompareMode7420 RTDHANDLE hBoard
7. About Counter Functions EnableAcntStop7420 LoadAcnt7420 SetupAboutCounter7420 Sample Counter Functions SetAdcntSource7420 LoadAdcnt7420 SetupSampleCounter7420 Digital I O Functions ClearDIO7420 ClearDIO0IrqStatus4 EnableDIOOIrq7420 GetDIOO0Clock7420 GetDIOOCompareMode7420 GetDIOOCompare Value7420 GetDIO0Direction7420 GetDIO 1 Direction7420 GetDIOOMask7420 GetDIOStatus7420 PollDI007420 ReadDIO07420 ReadDIO17420 SelectDIOORegister7420 SetDIO0Clock7420 SetDIOOCompareMode7420 SetDIOOCompare Value7420 SetPortODirection7420 SetPort 1 Direction7420 SetDIOODirection7420 SetDIO 1Direction7420 SetDIOOMask7420 WriteDI007420 WriteDIO17420 22 90 DM7420 Data Acquisition Driver for Windows 95 98 NT High Speed Digital Input Functions StartHdin7420 SetHdinStart7420 User Input Output Functions ReadUserInput7420 Write UserOutput7420 SetUoutOSource7420 SetUout 1 Source7420 User Timer Counter Functions GetTimerStatus7420 SetUtcOClock7420 SetUtcOGate7420 SetUtc1Clock7420 SetUtc1Gate7420 SetUtc2Clock7420 SetUtc2Gate7420 Set8254Divisor7420 Set8254Mode7420 Get8254Mode7420 Get8254Count7420 Get8254Status7420 SetupTimerCounter7420 ReadTimerCounter7420 KickCounter7420 Interrupt Handling GetITStatus7420 SetITMask7420 ClearITMask7420 ReadITOverrun7420 ClearITOverrun7420 SetEintPolarity7420 EnableDIOOIrq7420 ClearDIO0IrqStatus7420 InstallCallbackIRQHandler7420 InstallCounterIRQHandler7420 RemovelRQHandler7420
8. hardware through the WinRT driver The RTD board drivers has multiboard feature It means that it is possible to use more than one board in the system Each board requires a unique WinRT device to handle the hardware The maximum number of devices on Windows NT is 32 on Windows 95 98 is 10 The Driver API Functions The resources on the DM7420 board can be accessed from Windows through the driver API Application Programming Interface functions The executable code of these functions is located in the DM7420 DLL file To write applications using the API functions you must include the DM7420 H header file and link the program with the DM7420 LIB import library file In the example programs you can find examples on using the driver Using the Driver without the Windows GUI This driver is based on the Win32 system and can run only under Windows However the user who is not familiar with the Windows Graphical User Interface can use the driver API functions in Win32 console applications which has an MS DOS like text mode interface In console applications is not necessary to use the Windows graphical environment but all the driver s API functions are accessible The Microsoft Visual C compiler supports writing console applications DM7420 Data Acquisition Driver for Windows 95 98 NT 7 90 8 90 DM7420 Data Acquisition Driver for Windows 95 98 NT DM7420 Features Measurement Scenarios Through selecting different option
9. uint8 GetDIOStatus7420 RTDHANDLE hBoard Description Read Digital I O status Parameters hBoard device handle Return Value DO DI register opened for programming D2 Port 1 direction 0 input 1 output D3 Digital IRQ Mode 0 Event 1 Match D4 Digital IRQ Enable 0 disabled I enabled D5 Digital Sample Clock Select 0 SM oscillator 1 User TC Counter 1 D6 Digital IRQ Status 0 no IRQ I IRQ D7 Strobe Status See Also Advanced Digital Trigger GetErrorStatus7420 Syntax BOOL GetErrorStatus7420 RTDHANDLE hBoard LONG ErrorCode Description Return last error code for a given board and clears the internal error status variable i e a second call to this function will return FALSE indicating no error 38 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Parameters hBoard device handle ErrorCode pointer to a location to return the error code Return Value TRUE If there is an error FALSE If there is no error GetFifoStatus7420 Syntax uintl6 GetFifoStatus7420 RTDHANDLE hBoard Description Return the status of all board FIFO buffers Parameters hBoard device handle Return Value Bit 0 0x0001 Not used Bit 1 0x0002 Not used Bit 2 0x0004 Not used Bit 3 0x0008 0 reserved Bit 4 0x0010 Not used Bit 5 0x0020 Not used Bit 6 0x0040 Not used Bit 7 0x0080 0 reserved Bit 8 0x0100 ADC FIFO not empty Bit 9 0x0200 ADC FIFO n
10. which is displayed in the polling loop WAUTOINC GUI MFC Example Example on high speed reading of FIFO buffers This example samples an Analog Input channel at 25kHz and monitors samples on the screen This example uses the first installed DM7420 A D converter is set up for Pacer Clock controlled conversions The Internal Pacer Clock is programmed for 25kHz software start stop Cannel Gain Latch is set up for sampling AIN1 single ended channels in 5Volts bipolar range Interrupts are enabled on About Counter countdown When the Start button is pressed an interrupt handler is installed the Pacer Clock is started and a Windows timer is programmed to provide the main polling loop The interrupt handler reads 512 samples from the A D FIFO using the block read API function In the polling loop the latest 512 samples are monitored on a graph WCALLBACK GUI MFC Example The board is programmed to sample the analog input with the pacer clock On A D conversion the board generates an interrupt and the interrupt routine calls the user defined callback function to process the data WCGT GUI MFC Example Example on using the Channel Gain Table DM7420 Data Acquisition Driver for Windows 95 98 NT 87 90 This example samples two Analog Input channels and saves data to disk On the screen it monitors number of samples saved This example uses the first installed DM7420 A D converter is set up for Pacer Clock controlle
11. 83 90 84 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Example Programs Reference All example programs are Win32 applications Board Feature Example Program to demonstrate feature Analog Input WSOFTTRIG WINTRPTS WCALLBACK WAUTOINC WCGT W2BOARDS Digital I O WDIGITAL Pacer Clock WINTRPTS WCALLBACK WAUTOINC WCGT W2BOARDS User Timer Counters WTIMERS Pre Post Triggering Channel Gain Table Interrupts WINTRPTS WCALLBACK WAUTOINC WCGT W2BOARDS Using multiple boards W2BOARDS DM7420 Data Acquisition Driver for Windows 95 98 NT 85 90 86 90 DM7420 Data Acquisition Driver for Windows 95 98 NT 2BOARDS GUI MFC Example Example on using two DM7420 boards in an application This example samples AIN1 on two DM7420s Sampling on the two boards can be started stopped independently This example uses the first two installed DM7420 boards Both boards are configured in the same way A D converters are set up for Pacer Clock controlled conversions The Internal Pacer Clocks are programmed for 10Hz software start stop Cannel Gain Latches are set up for sampling AIN1 single ended channels in 5Volts bipolar range Interrupts are enabled on A D FIFO Write When a Start button is pressed an interrupt handler is installed for the corresponding board its Pacer Clock is started and a Windows timer is programmed to provide the a polling loop The interrupt handlers read 1 sample from the A D FIFO
12. Arm the Pacer Clock to be ready for receiving the start trigger StartPacer7420 hBoard DU Post Triggering Post triggering scheme enables you to stop sampling with some delay after an event trigger sampling Trigger This scheme is for situations where you want to take a known number of samples after an important event This scheme is realized by using the About Counter Follow the steps below to set up for this scheme 1 Allocate a buffer which is big enough to hold the desired number of samples nsamples after the event 2 Set up the Pacer Clock to start on the desired event and to stop when About Counter counts down to zero SetPacerStart7420 hBoard PCLK START SOFTWARE SetPacerStop7420 hBoard PCLK STOP A xxx 3 Initialize the About Counter for the number of samples you want to be collected after your trigger event SetupAboutCounter7420 hBoard nsamples TRUE 16 90 DM7420 Data Acquisition Driver for Windows 95 98 NT 4 Set up a mechanism to copy samples from the A D FIFO to your sample buffer For example install an interrupt handler to copy data by 512 samples SetupSampleCounter7420 hBoard TC ADC SCNT ADC SCNT FIFO WRITE 512 M8254 RATE GENERATOR InstallCallbackIRQHandler7420 hBoard handler IROM AD SCNT SetITMask7 420 hBoard IRQM AD SCNT 5 Arm the Pacer Clock to be ready for receiving the start trigger StartPacer7420 hBoard When the trigger occurs About Counter wi
13. Gain Table Reset event Consider this if you have a sample counter A D Sample Counter or the About Counter configured to count these events or you enabled this event to be an interrupt source Parameters hBoard device handle See Also Channel Gain Circuitry 58 90 DM7420 Data Acquisition Driver for Windows 95 98 NT SelectDIOORegister7420 Syntax void SelectDIO0Register7420 RTDHANDLE hBoard int aReg Description Program digital control register Parameters hBoard device handle aReg 0 Clear Command 1 Direction Register 2 Mask Register 3 Compare Register Set8254Divisor7420 Syntax void Set8254Divisor7420 RTDHANDLE hBoard int counter uintl6 divisor Description Load an initial count in a Timer Counter Parameters hBoard device handle counter One of the 16 bit timer counters of the board Use TC_XXXX for argument counter divisor 16 bit divisor to divide clock input frequency See Also Timer Counters Set8254Mode7420 Syntax void Set8254Mode7420 RTDHANDLE hBoard int counter uint8 mode Description Load count in Timer Counter 0 8 bit DM7420 Data Acquisition Driver for Windows 95 98 NT 59 90 Parameters hBoard device handle counter One of the 16 bit timer counters of the board Use TC XXXX for argument counter TC PCLK16 Pacer Clock 0 TC_PCLK32 Pacer Clock 1 TC BCLK Burst Clock TC ADC SCNT A D Sample counter TC_DCNT Delay Counter TC_ACNT About
14. GetIRQCounter7420 External Trigger Configuration Functions SetEtrgPolarity 7420 DM7420 Data Acquisition Driver for Windows 95 98 NT 23 90 24 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Alphabetical Driver API Functions Reference DM7420 Data Acquisition Driver for Windows 95 98 NT 25 90 26 90 DM7420 Data Acquisition Driver for Windows 95 98 NT ClearADFIFO7420 Syntax void ClearADFIFO7420 RTDHANDLE hBoard Description Dispose all samples from the A D FIFO NOTE Reading from an empty FIFO e g with ReadADData7420 ReadADDataWithMarker7420 GetAutoIncDataByte7420 or GetAutoIncDataWord7420 results in indeterministic data Parameters hBoard device handle ClearAlll07420 Syntax void ClearAllI07420 RTDHANDLE hBoard Description Software reset of the board Parameters hBoard device handle ClearCGT7420 Syntax void ClearCGT7420 RTDHANDLE hBoard Description Clear A D Channel Gain Table This function removes all entries from the CGT Use this function before reprogramming the CGT This is the only way to remove entries from the CGT There is no way to insert remove a single CGT entry or change it in place NOTE This function clears the Digital part of the CGT Parameters hBoard device handle See Also Channel Gain Circuitry DM7420 Data Acquisition Driver for Windows 95 98 NT 27 90 ClearDinFifo7420 Syntax void ClearDinFifo7420 RTDHANDLE hBoard
15. RTDHANDLE hBoard uintl6 start uintl6 stop uintl6 repeat uintl6 src float rate Description Configure the Pacer Clock Select start stop trigger single or repeat mode internal or external pacer clock source rate See the individual SetPacerxxx functions Parameters hBoard device handle start Pacer Start trigger see SetPacerStart7420 stop Pacer Stop trigger see SetPacerStop7420 repeat Pacer Clock retriggering mode see SetPacerRepeat7420 src Pacer Clock select see SetPacerSource7420 rate Pacer Clock rate in Hertz Ignored if Pacer Clock source src is External Pacer Clock DM7420 Data Acquisition Driver for Windows 95 98 NT 67 90 SetPacerRate7420 Syntax void SetPacerRate7420 RTDHANDLE hBoard float rate Description Program Pacer Clock rate Parameters hBoard device handle rate Clock frequency Hertz Valid values are between 0 0018Hz and 600KHz SetPacerRepeat7420 Syntax void SetPacerRepeat7420 RTDHANDLE hBoard uintl6 repeat Description Pacer Start Trigger Mode select Parameters hBoard device handle repeat 0x0 Single Cycle Mode New cycle is possible only after a Software Pacer Start command StartPacer7420 Ox1 Trigger Repeat Mode Pacer Clock can be restarted by the selected Pacer Start Trigger Use PCLK NO REPEAT PCLK REPEAT for argument repeat SetPacerSource7420 Syntax void SetPacerSource7420 RTDHANDLE hBoard uintl6 src Des
16. adding to an existing table the new data written will be added at the end NOTE Remember to select Channel Gain Table to control sampling see EnableCGT7420 Parameters hBoard device handle entry table entry See Also Channel Gain Circuitry WriteCGTDigital7420 Clear CGT7420 WriteCGT Digital7420 Syntax void WriteCGTDigital7420 RTDHANDLE hBoard uint8 entry Description Channel Gain Digital Output Write Digital table To control external MUX NOTE The first entry made into the Digital Table lines up with the first entry made into the Analog Table the second entry made into the Digital Table lines up with the second entry made into the Analog Table and so on Make sure that if you add to an existing table and did not program the Digital Table portion when you made your Analog Table entries previously you fill those entries with digital data first before entering the desired added data Since the first digital entry you make always lines up with the first analog entry made failure to do this will cause the analog and digital control data to be misaligned in the table NOTE You cannot turn the digital control lines off for part of a conversion sequence and then turn them on for the remainder of the sequence Note that the digital data programmed here is sent out on the Port digital I O lines whenever this portion of the table is enabled by the EnableCGTDigital7420 DM7420 Data Acquisition Driver for Windows
17. can be used to control input expansion boards such as the TMX32 Analog Input Expansion board The expansion board is driven at the same speed as the A D conversions are performed with no software overhead EXAMPLE Let us consider the following simple example on driving an analog input expansion board In this example we have a TMX32 expansion board connected to AIN1 on the DM7420 We have three signals to sample one is connected to the first channel of the expansion board EAIN1 the second is connected to the fourth channel of the expansion board EAIN4 and the third is connected directly to AIN2 of the DM7420 We need to create the following Channel Gain Table 12 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Entry 1 AIN1 gain 1 DO 0 Entry 2 AIN1 gain 4 DO 3 Entry 3 AIN2 gain 1 DO 3 Execution starting with entry 1 samples AIN1 and simultaneously outputs 0 on Digital Port 1 This will cause the expansion board to switch to EAIN1 Entry 2 will sample AIN1 which is now connected to EAINI and simultaneously outputs 3 on Digital Port 1 As a result the expansion board switches to EAIN4 Next entry 3 samples AIN2 and outputs 3 on Digital Port 1 which makes the expansion board to switch again to EAIN4 When executing entry 1 again AIN1 is sampled which is now connected to EAIN4 and so on To load the Channel Gain Table you need to follow the steps below SetupCgtRow7420 sentry 0 GAIN1 AIN_BI
18. to the fractional number of samples and enable Sample Counter stop Example Suppose you want to count 500 000 samples with the About Counter In this case first you load the initial count of 65 535 disable About Counter stop and install an interrupt handler for About Counter Count Down In the interrupt handler you maintain a counter for the turnovers After 500 000 65 535 7 you load the fractional count 500 000 7 65 535 41 255 and enable About Counter stop Parameters hBoard device handle enable 0 Stop enabled 1 Stop disabled EnableCGT7420 Syntax void EnableCGT7420 RTDHANDLE hBoard uintl16 enable Description Select Channel Gain Table or Channel Gain Latch to use for A D sampling Parameters hBoard device handle enable CSC LATCH 0 Channel Gain Table disabled Channel Gain Latch enabled CSC CGT 1 Channel Gain Table enabled Channel Gain Latch disabled DM7420 Data Acquisition Driver for Windows 95 98 NT 31 90 See Also Channel Gain Circuitry EnableCGTDigital7420 EnableCGTDigital7420 Syntax void EnableCGTDigital7420 RTDHANDLE hBoard uint16 enable Description Enable disable Digital Table NOTE This function has no effect if you use the Channel Gain Latch Parameters hBoard device handle enable FALSE 0 Digital Table disabled Digital I O P1 port enabled TRUE 1 Digital Table enabled Digital I O P1 port disabled See Also Channel Gain Circ
19. when any of the selected lines changes event mode Mode is selected by the SetDIO0CompareMode7420 function When Advanced Digital Interrupt modes enabled see EnableDIO0Irq7420 digital lines are sampled at either at 8 MHz or at the rate of User Timer Counter 1 Clock is selected by the SetDIOOClock7420 function Only lines enabled in the Mask Register set by SetDIOOMask7420 take part in monitoring With each clock pulse the digital circuitry looks at the state of the next Port 0 bits To provide noise rejection and prevent erroneous interrupt generation because of noise spikes on the digital lines a change in the state of any bit must be seen for two edges of a clock pulse to be recognized by the circuit In Event Mode the enabled Port 0 input lines are monitored for a change When any of these lines change an interrupt is generated and the input pattern is latched into the Compare Register You can read the contents of this register with GetDIOOCompareValue7420 to see which bit caused the interrupt to occur In Match Mode the enabled Port 0 input lines are monitored for the value programmed in the Compare Register with SetDIOOCompare Value7420 to occur When lines match this value an interrupt is generated When Advanced Digital Interrupt mode is not enabled see EnableDIO0Irq7420 the Mask Register can be used to preserve a bit s state regardless of the digital data written to Port 0 In addition external data can be strobed into P
20. 1 BURST CEOCK HANDLING vasset Are RR Gerner ei it 22 DELAY COUNTER Oe HE 22 ABOUT COUNTER FUNCTIONS eiere soessdeecaveossdesssicaucdessus edebeedaedusseetdecsesbeseue 22 SAMPLE COUNTER FUNCTIONS csssssssssecececsesssaececcsensaececececseseeeeccecsesesaeseeececeeseaseeeceeseseeaeees 22 DIENEN NO RO e KEEN 22 HIGH SPEED DIGITAL INPUT FONCTION 23 USER INPUT OUTPUT FUNCTIONS srrrnnorrrnrorrrennnnrrrnrnrrennnnrrenserssennnnrsnnsnenennrnnnensnnenannnnnsessennsnnnnns 23 USER TIMER COUNTER FUNCTIONS este eereen treere r enter rener kreere renee erne treere rener erennee 23 INTERRUPT HANDLING eege kreeg EENEG EECH 23 EXTERNAL TRIGGER CONFIGURATION ROUNGCTIONS eee enke eee er tere ener errnee 23 ALPHABETICAL DRIVER API FUNCTIONS REFERENCE eeranovrvvorrornannrnrnrnrsnrsnnrnnnennsnensnnrnnnvnssennner 25 EXAMPLE PROGRAMS REFERENCE soooseessssesvseenssnsnnsensssennssssssnsnnsssnssssnesensnsesnssennnsenne 85 2BOARDS GUI MFC EXAMPLE reoororvorrnennnnrnrnrnrsnnnsnnrensnrsnennnnrnnnsnssnannnnnenssnenannnnnnensnssnnnnnns 87 WAUTOINC GUI MFC ESAMPLE tere ernen ener eerenn tree seernes rnnee 87 WCALLBACK GUI MFC SAMPLE 87 WCGT GUI MFC EXAMPLE ee 87 WDIGITAL GUI OMC EXAMPLE raa er EE EEEE harer EEEE E Sia 88 WINTRPTS GUI MFC EXAMPLE rrsrornrnnrvvnrennrnenrsnvrnssnnrensennrnesssnnrnsennrnerennnnssssnnenssnnrnsssnnnnsere 88 WSOFTTRIG GUI MFC SAMPLE 88 WTIMERS GUI MFC SAMPLE 88 iii Introduction The DM7420 data acquisition b
21. 95 98 NT 81 90 Parameters hBoard device handle entry table entry See Also Channel Gain Circuitry WriteCGTAnalog7420 ClearCGT7420 WriteCGTLatch7420 Syntax void WriteCGTLatch7420 RTDHANDLE hBoard uintl6 entry Description Write ADC channel gain latch Single channel mode NOTE Remember to select Channel Gain Latch to control sampling see EnableCGT7420 Parameters hBoard device handle entry latch entry See Also Channel Gain Circuitry WriteDI007420 Syntax void WriteDI007420 RTDHANDLE hBoard uint8 value Description Set Digital Port 0 output lines NOTE Bits in argument value are ignored for lines which are programmed for input Parameters hBoard device handle value 8 bit value to write to port WriteDIO1 7420 Syntax void WriteDIO17420 RTDHANDLE hBoard uint8 Data Description Write to Digital I O Port 1 82 90 DM7420 Data Acquisition Driver for Windows 95 98 NT NOTE This function has no effect if Digital I O Port 1 is programmed for input Parameters hBoard device handle Data data out WriteUserOutput7420 Syntax void WriteUserOutput7420 RTDHANDLE hBoard Description This routine is used to write User Output Line 0 amp 1 Parameters hBoard device handle data output value only bits 0 and I are used Bit 0 Value for User Output Line 0 Lin Bit Value for User Output DM7420 Data Acquisition Driver for Windows 95 98 NT
22. Counter TC_UTCO User TC 0 TC UTC1 User TC 1 TC UTC2 User TC 2 mode One of the 6 8254 operation modes Use M8254 XXXX for argument model M8254 EVENT COUNTER Event Counter M8254 HW ONE SHOT Hardware Retriggerable One Shot M8254 RATE GENERATOR Rate Generator M8254 SQUARE WAVE Square Wave Mode M8254 SW STROBE Software Triggered Strobe M8254 HW STROBE Hardware Triggered Strobe Retriggerable SetAdcntSource7420 Syntax void SetAdcntSource7420 RTDHANDLE hBoard uintl6 src Description Select A D Sample Counter source Parameters hBoard src 60 90 device handle Use ADC SCNT XXXX for argument src ADC SCNT CGT RESET 0 Count Channel Gain Table resets Counter counts down by one when the Channel Gain table turns over to the first table entry ADC SCNT FIFO WRITE 1 Count A D FIFO writes Counter counts down by one when a new sample is entered in the FIFO DM7420 Data Acquisition Driver for Windows 95 98 NT SetBurstRate7420 Syntax void SetBurstRate7420 RTDHANDLE hBoard float rate Description Program the burst clock rate Parameters hBoard device handle rate Frequency value Hertz between 122Hz and 600KHz SetBurstStart7420 Syntax void SetBurstStart7420 RTDHANDLE hBoard uintl6 src Description Select Burst Clock start trigger NOTE There is no programmable stop trigger for the Burst Clock The Burst Clock automatically stops when the Channel Gain Table resets
23. DM7420 Data Acquisition Driver for Windows 95 98 NT User s Manual Real Time Devices USA Inc Table of Contents TABLE OF CONTENTS siccvestscicssacesiancodss ouccavevescsensscbnesnosstasenegsvenseesscssaasevenessaseusesvenesensescase II INTRODUCTION aicsccssicccssedseconsccsncssocesessnsnnssbecsesnnseudecyeoncsevessosteseasednssesdecstshevesesssteseasesenveonass 5 INSTALLATION HEEN 5 INSTALLATION OF THE DRIVER AND EXAMPLE PROGRAMS sssseeeeeeeeeeree seeren terne entreen ener rer 5 THE DM7420 EIER EAR OC 7 THE DRIVER API FUNCTIONS desse sees ee deer ege desidert d ve 7 USING THE DRIVER WITHOUT THE WINDOWS OUT 7 DM7420 FEATURES EE 9 MEASUREMENT SCENARIOS r E ene E TE EOE eder E AN rE eaS 9 CHANNEL GAIN CIRCUTTRY inon an E EA E E E i a 10 INTERR UPS SE EEE EE EE E EK EEEE AE EE EEEE E EEEE 14 PRE AND POST TRIGGERIN O ane 15 ADVANCED DIGITAL TRIGGER 18 DRIVER API FUNCTION GROUPS esosssesessssssssssnsessneesnsssssseesnssesssnensnsseneesssssssneesssnssnssenses 21 DRIVER INITIALIZATION FUNCTIONS ccsccccccecsesssseceeececessscececececsesseaecececeseseseceeccseseseaesesceeeas 21 GENERAL BOARD CONTROL FUNCTIONS MMuG sssssceseeeeeereereeren er eeren entreen entreen entreen ener er err renerne 21 ELEO MANIPULATION As ie avse ee erre 21 A D CONVERTER vesenet 21 CHANNEL GAIN TABLE MANIPULATION cccccsesssccsececeesenseecececseseaeeecccecsessseeececeesenssaeseeeeeeees 21 PAGER CLOCK HANDLING enge EES AU ee EE ege eg 2
24. E GENERATOR Set8254Divisor7420 hBoard TC DCNT samples KickCounter7420 hBoard TC DCNT Parameters hBoard device handle samples SetupSampleCounter7420 Syntax I void SetupSampleCounter7420 RTDHANDLE hBoard int counter uintl6 src uintl6 divisor uint8 mode Description Program one of the 3 sample counters NOTE This function is a short for the following calls switch counter case TC_ADC_SCNT SetAdcntSource7420 hBoard src break SetupTimerCounter7420 hBoard counter mode divisor KickCounter7420 hBoard counter Parameters hBoard device handle counter Use TC XXXX for argument counter source Use ADC SCNT XXXX for argument src divisor 16 bit initial count mode one of the 6 8254 modes SetupTimerCounter7420 Syntax I void SetupTimerCounter7420 RTDHANDLE hBoard int counter uint8 mode uintl6 divisor Description Program a 8254 Timer Counter NOTE This function is a short for the following calls DM7420 Data Acquisition Driver for Windows 95 98 NT 75 90 Set8254Mode7420 hBoard counter mode Set8254Divisor7420 hBoard counter divisor Parameters hBoard device handle counter One of the 16 bit timer counters of the board Use TC XXXX for argument counter mode One of the 6 8254 operation modes Use M8254 XXXX for argument model divisor 16 bit divisor to divide the clock input frequency SetUtcOClock7420 Syntax vo
25. P5 0 GND_SE 0 0 0 0 WriteCGTAnalog7420 0 entry entry 1 analog WriteCGTDigital7420 0 0 entry 1 digital SetupCgtRow7420 amp entry 0 GAIN4 AIN BIP5 0 GND SE 0 0 0 0 WriteCGTAnalog7420 0 entry entry 2 analog WriteCGTDigital7420 0 3 entry 2 digital SetupCgtRow7420 Sentry 1 GAIN1 AIN_BIP5 0 GND_SE 0 0 0 0 WriteCGTAnalog7420 0 entry entry 3 analog WriteCGTDigital7420 0 3 entry 3 digital EnableCGT7420 0 CSC_CGT enable CGT vs CGL EnableCGTDigital7420 0 CSC CGT enable Digital Table NOTE If you only need to use the A D part of the table you do not have to program the Digital Table However if you only want to use the Digital part of the table you must program the A D part of the table NOTE When the Channel Gain Latch is used Digital Table is ignored When using the Channel Gain Table you should group your entries to maximize the throughput of your module Low level input signals and varying gains are likely to drop the throughput rate because low level inputs must drive out high level input residual signals To maximize throughput Q Keep channels configured for a certain range grouped together even if they are out of sequence Q Use external signal conditioning if you are performing high speed scanning of low level signals This increases throughput and reduces noise DM7420 Data Acquisition Driver for Windows 95 98 NT 13 90 If you have roo
26. T_TC_CLOCK2 2 Connect User T C2 clock input to the External TC Clock 2 pin on the I O connector CUTC2 EXT PCLK 3 Connect User T C2 clock input to the External Pacer Clock pin on the I O connector CUTC2 UTC1 OUT 4 Connect cascade User T C2 clock input to User T C1 out SetUtc2Gate7420 Syntax void SetUtc2Gate7420 RTDHANDLE hBoard uintl6 src Description User Timer Counter 2 Gate Select Parameters hBoard device handle srce GUTC2_NOT_GATED 0 78 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Connect User T C2 Gate to 5 Volts let clock run GUTC2 GATED 1 Connect User T C2 Gate to the ground stop clock GUTC2 EXT TC GATEI 2 Connect User T C2 Gate to the External TC Gate 1 pin on the I O connector GUTC2_EXT_TC_GATE2 3 Connect User T C2 Gate to the External TC Gate 2 pin on the I O connector GUTC2_UTC1_OUT 4 Connect User T C2 Gate to User T C1 out StartConversion7420 Syntax void StartConversion7420 RTDHANDLE hBoard Description This routine is used to generate a software trigger or enable hardware triggers depending on the programmed A D conversion signal SetConversionSelect7420 Parameters hBoard device handle StartBurst7420 Syntax void StartBurst7420 RTDHANDLE hBoard Description Generate a software Burst Clock start NOTE This function is needed and has only effect if Burst Clock is programmed for software start see SetBurs
27. and makes them available for other applications NOTE After closing a board no driver functions may be called but OpenBoard7420 Parameters hBoard Board to close szBuf Message buffer to return error message if any error occurs during closing the board Return Value TRUE Board is closed successfully FALSE There was an error while closing the board See GetErrorStatus7420 for the error occurred 30 90 DM7420 Data Acquisition Driver for Windows 95 98 NT EnableAcntStop7420 Syntax void EnableAcntStop7420 RTDHANDLE hBoard uint16 enable Description Enable disable About Counter to stop when it counts down to zero Default setting is enabled The About Counter is a 16 bit down counter that stops or reloads the initial count value after counting down to zero The About Counter counting at the rate of the Pacer Clock can be used to count samples When About Counter stop enabled the counter stops when it counts down to zero If you disable About Counter Stop the counter keeps reloading the initial counter value when it reaches zero In both cases you may program the board to generate an interrupt When stop disabled you can install your own interrupt handler for the About Counter countdown event and keep track of the turnovers Use this mode to extend the counting capability highest number than 65535 In the interrupt handler when the counter counted the desired number of samples you have to reprogram the counter
28. aneous sample and hold board can be used SS8 eight channel boards are available from Real Time Devices DM7420 Data Acquisition Driver for Windows 95 98 NT 9 90 Q Programmable Multi Scan This mode when the A D Conversion Start Signal is the Burst Clock lets you scan the Channel Gain Table after a Burst Clock Start Signal When the Channel Gain Table is empty the Burst Clock is stopped and will wait for a new Start Signal Channel Gain Circuitry Channel Gain Tables are traditionally for implementing random channel scan analog input on boards where a single A D converter is multiplexed for 8 16 or more analog input channels DM7420 features a more advanced Channel Gain Circuitry which actually provides synchronous Analog and Digital I O The Channel Gain Circuitry embeds a 1024x24 bit on board memory Channel Scan Memory called Channel Gain Table CGT for historical reasons Every 24 bit row entry in a CGT is an instruction executed by the Channel Gain circuitry Execution happens at a programmable rate Channel Gain Latch CGL provided for easy single channel analog input can be perceived as a special single row CGT for the following description Unless explicitly indicated explanation holds for the CGL as well The table below pictures the format of a CGT entry Skip Pause Se Diff Range NRSE Gain Channel 8 bits 1 bit 1 bit 1 bit 2 bits 1 bit 3 bits 4 bits Channel Analog Input Ch
29. annel Specifies the Analog Input channel to sample Depending on your configuration you may have 8 differential channels AIN1 AIN8 or 16 Single Ended channels AIN1 AIN16 Gain Analog Input Gain This field specifies the gain to apply to the input Available choices arelx 2x 4x 8x 16x 32x 64x 128x Range Analog Input Range Specifies one of the three supported input ranges 5 Volts 10 Volts or 0 10Volts Se Diff Analog Input Type NRSE Non Referenced Single Ended Bit These two bits together determine the type of the analog input channel Ground Referenced Single Ended GRSE Se Diff 0 NRSE 0 This mode is suggested only for floating signal sources to avoid the ground loops For this input type the reference signal of Instrumentation Amplifier is the Analog Ground To configure a GRSE analog input connect the high side of the input signal to the selected analog input channel AIN1 AIN16 and connect the low side to any of the Analog Ground pins of the I O connector If you use the channels AIN9 AIN16 switch the appropriate SW1 and SW2 dips off See Hardware Manual for more Non Referenced Single Ended NRSE Se Diff 0 NRSE 1 This mode can be used for grounded signal sources and for floating sources as well For this input type the reference signal of Instrumentation Amplifier is the 10 90 DM7420 Data Acquisition Driver for Windows 95 98 NT AINSENSE signal In the case of floating sources an external re
30. ard nsamples2 TRUE DM7420 Data Acquisition Driver for Windows 95 98 NT 17 90 4 Set up a mechanism to copy samples from the A D FIFO to your sample buffer For example install an interrupt handler to copy data by 512 samples SetupSampleCounter7420 hBoard TC ADC SCNT ADC SCNT FIFO WRITE 512 M8254 RATE GENERATOR InstallCallbackIRQHandler7420 hBoard handler IROM AD SCNT SetITMask7420 hBoard IRQM AD SCNT 5 Start the Pacer Clock StartPacer7420 hBoard When the trigger occurs About Counter will start and sampling stops after nsamples2 At this point your sample buffer s last nsamples1 nsamples2 elements will contain the data you needed If you want to take more than 65 535 samples after the trigger you also need to do the following 3 Change About Counter setup to disable it stopping when it counts down to zero and install an interrupt handler on About Counter Countdown SetupAboutCounter7420 hBoard nsamples2 FALSE InstallCallbackIRQHandler7420 hBoard handler IROM ABOUT CNT 6 Inthe About Counter interrupt handler count the Countdowns and enable About Counter to stop when the required number of samples has been taken EnableAcntStop7420 hBoard TRUE Advanced Digital Trigger The bit programmable Digital I O Port 0 supports two Advanced Digital Interrupt modes Port can be programmed to generate an interrupt when selected port lines match a programmed value match mode or
31. ate7420 hBoard rate Parameters hBoard device handle DM7420 Data Acquisition Driver for Windows 95 98 NT 73 90 start Burst Trigger source rate Burst clock rate in Hertz SetupCgtRow7420 Syntax void SetupCgtRow7420 ioctrl t cscRow int aChannel int aGain int aRange int aNRSE int aGround int aPause int aSkip Description Setup a Channel Gain Table entry Parameters ioctrl_t cscRow structure for CGT rows aChannel Analog Input channel to sample 0 15 for AIN1 AIN16 aGain Analog Input gain to apply on the analog input 0 7 for gains 1x 2x 4x 8x 16x 32x 64x and 128x respectively aRange Analog Input range AIN BIP5 0 5 Volts AIN_BIP10 1 10 Volts AIN_UNIP10 2 0 10 Volts aNRSE Ground referencing mode NRSE_AGND 0 Non Ground Referenced Single Ended NRSE_AINS 1 Ground Referenced Single Ended aGround Analog Input Type GND_SE 0 Single Ended GND_DIFF 1 Differential aPause Pause Bit 0 do not pause CGT execution 1 pause CGT execution aSkip Skip Bit 0 store converted A D sample to FIFO 1 discard converted A D sample See Also Channel Gain Circuitry WriteCGTAnalog7420 SetupDelayCounter7420 Syntax void SetupDelayCounter7420 RTDHANDLE hBoard uint16 samples Description Program the delay counter 74 90 DM7420 Data Acquisition Driver for Windows 95 98 NT NOTE This function is a short for the following calls Set8254Mode7420 hBoard TC DCNT M8254 RAT
32. atus7420 RTDHANDLE hBoard Description Read Timer Counters Status Parameters hBoard device handle Return Value Bit 0 Pacer Clock Gate status 0 clock is gated not running 1 clock is running Bit 1 Burst Clock Gate status 0 clock is gated not running 1 clock is running Bit 2 Pacer Clock Delayed Start Trigger status 0 delay over 1 delay in progress 40 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Bit 3 Pacer Clock About Trigger status 0 completed 1 in progress Bit 4 Pacer Clock Shutdown Flag status 0 Pacer Clock can be start triggered only by Software Pacer Start Command 1 Pacer Clock can be start triggered See TS XXXX symbolic constants DM7420 Data Acquisition Driver for Windows 95 98 NT 41 90 42 90 DM7420 Data Acquisition Driver for Windows 95 98 NT InitBoard7420 Syntax void InitBoard7420 RTDHANDLE hBoard Description Resets the board to power up defaults and clears all FIFO buffers and the CGT NOTE It is a good practice to call this function after opening a board for use Parameters hBoard device handle InstallCallbackIRQHandler7420 Syntax void InstallCallbackIRQHandler7420 RTDHANDLE hBoard isr t handler uintl6 mask Description Install interrupt handler function NOTE The handler parameter is not a real interrupt handler It is a callback function that is scheduled for execution by the interrupt service routine Your handle
33. cription Select Pacer Clock Source Parameters hBoard device handle src 0x0 External Pacer Clock Ox1 Internal Pacer Clock Use PCLK_XXXX for argument src 68 90 DM7420 Data Acquisition Driver for Windows 95 98 NT SetPacerStart7420 Syntax void SetPacerStart7420 RTDHANDLE hBoard uintl6 src Description Select Pacer Clock start trigger Parameters device handle PCLK START SOFTWARE 0x0 Pacer Clock is started by a call to StartPacer7420 PCLK_START_ETRIG 0x1 A positive or negative going edge depending on the setting of the trigger polarity SetEtrgPolarity7420 on the external TRIGGER INPUT line will start the Pacer Clock The pulse duration should be at least 100 nanoseconds NOTE If the Pacer Clock is already running when an External Trigger occurs behavior depends on the programmed Pacer Clock Repeat Mode see SetPacerRepeat7420 PCLK_START_DIGITAL_IT 0x2 Pacer Clock is started when a Digital Interrupt occurs PCLK_START_UTC2 0x3 Pacer Clock is started by User T C 2 when counter reaches 0 PCLK_START_SBUSO 0x4 PCLK START SBUS1 0x5 PCLK START SBUS2 0x6 Pacer Clock is started by a positive edge of Synchron Bus line 0 1 2 respectively PCLK START D SOFTWARE 0x8 PCLK START D ETRIG 0x9 PCLK START D DIGITAL IT OxA PCLK START D UTC2 0xB PCLK START D SBUSO 0xC PCLK START D SBUSI1 0xD PCLK START D SBUS2 OxE These start trigger sources provide delayed tr
34. d by the About Counter Pacer Clock stops when About Counter counts down to zero and About Counter Stop is enabled see EnableAcntStop7420 About Counter counts the samples that are actually entering the A D FIFO Use this mode for post triggering see Pre Post Triggering PCLK_STOP_UTC2 0x4 Pacer Clock stops when User T C2 counts down to zero PCLK_STOP_SBUSO 0x5 PCLK_STOP_SBUS1 0x6 PCLK_STOP_SBUS2 0x7 Pacer Clock is stopped when a rising edge occurs on Synchron Bus line 0 1 2 respectively PCLK_STOP_A_SOFTWARE 0x8 PCLK_STOP_A_ETRIG 0x9 DM7420 Data Acquisition Driver for Windows 95 98 NT PCLK STOP A DIGITAL IT OxA PCLK STOP A UTC2 0xC PCLK STOP A SBUSO 0xD PCLK STOP A SBUSO OxE PCLK STOP A SBUSO OxF These stop trigger sources are to provide about triggering see Pre Port Triggering When the selected stop trigger occurs About Counter starts counting the A D samples entering the A D FIFO When About Counter counts down to zero it stops the Pacer Clock SetPclkSize7420 Syntax void SetPclkSize7420 RTDHANDLE hBoard uintl6 size Description Select Pacer Clock size NOTE Pacer Clock size selection is ignored if Pacer Clock source is External Pacer Clock see SetPacerSource7420 Parameters hBoard device handle size PCLK_16BIT 0 16 bit divider A D converter connects to Pacer Clock 0 PCLK_32BIT 1 32 bit divider A D converter connects to Pacer Clock 1 that is cascaded
35. d conversions The Internal Pacer Clock is programmed for 1kHz software start stop Cannel Gain Table filled with two entries to sample AIN1 and AIN2 as single ended channels in 5 Volts bipolar range Interrupts are enabled on About Counter countdown When the Start button is pressed an interrupt handler is installed the Pacer Clock is started and a Windows timer is programmed to provide the main polling loop The interrupt handler reads 512 samples from the A D FIFO and saves them on disk In the polling loop the interrupt counter is monitored WDIGITAL GUI MFC Example Example on reading writing the Digital I O ports Digital I O Port 1 can be written by entering a value and pressing the Start button Port 0 is polled on a timely basis Hook back Port I to Port 0 to read back the value written to Port 1 on Port 0 This example uses the first installed DM7420 Digital I O Port 0 is programmed for input Port 1 is programmed for output A Windows timer is programmed to provide the main program loop In every iteration Port 0 is read and displayed on screen Pressing the Start button initiates writing to Port 1 WINTRPTS GUI MFC Example The board is programmed to sample the analog input with the pacer clock On A D conversion the board generates an interrupt WSOFTTRIG GUI MFC Example Example on doing simple Analog Digital conversions This example program does an A D conversion when a button is pressed This exa
36. e A D conversion is started by a call to StartConversion7420 ADC_START_PCLK 0x1 A D conversions are started by the Pacer Clock ADC_START_BCLK 0x2 A D conversions are started by the Burst Clock ADC_START_DIGITAL_IT 0x3 One A D conversion is started when a Digital Interrupt occurs 62 90 DM7420 Data Acquisition Driver for Windows 95 98 NT NOTE Remember to acknowledge the Digital Interrupt by calling ClearDIOOlrgStatus7420 Otherwise no newer Digital Interrupt is generated ADC START SBUS0 0x6 ADC START SBUS1 0x7 ADC START SBUS2 0x8 The A D converter is controlled by the signal on Synchron Bus line 0 1 2 Conversion started on a rising edge SetDIOOClock7420 Syntax void SetDIOOClock7420 RTDHANDLE hBoard uint8 src Description Select clock for the Advanced Digital Trigger Parameters hBoard device handle src 0 8 MHz On board Oscillator 1 User TC Counter 1 See Also Advanced Digital Trigger SetDIO0OCompareMode7420 Syntax void SetDIOO0OCompareMode7420 RTDHANDLE hBoard uint8 mode Description Programs port 0 compare mode This register is used for the Advanced Digital Interrupt modes Parameters hBoard device handle mode 0 Event Mode 1 Match Mode See Also Advanced Digital Trigger SetDIO0CompareValue7420 Syntax void SetDIOO0CompareValue7420 RTDHANDLE hBoard uint8 compare DM7420 Data Acquisition Driver for Windows 95 98 NT 63 90 Descrip
37. e all of the interrupt sources When the Interrupt Controller receives an interrupt request it transmits it to the PC Interrupt Controller to the IRQ line which is assigned to the board by the operating system In the Interrupt Service Routine reading the Interrupt Status Register via a call to GetITStatus7420 you can identify the causing interrupt source In this register there is a single non zero bit that indicates the signaling interrupt source If more than one interrupt source generates an interrupt at the same time this register will indicate the highest priority one The lower priority request is queued and will appear after acknowledging the higher priority one After identifying the source the interrupt can be serviced After servicing the request must be acknowledged by calling ClearITMask7420 Failing to do this makes the same interrupt reoccur repeatedly In normal operation the next interrupt request comes later than acknowledging the current one However if the next interrupt comes before acknowledging the current one i e interrupt overrun occurs you must be aware of it For this end DM7420 has an Interrupt Overrun Register Reading this register see GetITOverrun7420 after acknowledging the request enables you to determine a possible interrupt overflow To service interrupts with the DM7420 Driver you do not have to deal with all these chores Actually when you install your interrupt handler it is not a real Inter
38. every three seconds For this end we must create CGT with six entries Entry 1 AIN1 Skip Bit 0 Entry 2 AIN4 Skip Bit 1 Entry 3 AIN1 Skip Bit 0 Entry 4 AIN4 Skip Bit 1 Entry 5 AIN1 Skip Bit 0 Entry 6 AIN4 Skip Bit 0 Next we set the Pacer Clock to run at 2 Hz 0 5 seconds This allows us to sample each channel once per second the maximum sampling rate required by one of the channels pacer clock rate number of different channels sampled x fastest sample rate The first Pacer Clock pulse starts an A D conversion according to the parameters set in the first entry of the Channel Gain Table and each successive clock pulse incrementally steps through the table entries The first clock pulse takes a sample on AIN1 The second pulse looks at the second entry in the table and sees that the Skip Bit is set Sample is taken but is not stored in the FIFO The third pulse takes a sample on AIN1 again the fourth pulse skips the next entry and the fifth pulse takes our third reading on AIN1 On the sixth pulse the Skip Bit is disabled AIN4 is sampled and sample is stored to the FIFO Then the sequence starts over again with entry 1 Samples are not stored when they are not wanted saving memory and eliminating the need to throw away unwanted data NOTE When the Channel Gain Latch is used Skip Bit is ignored DO 8 Bit Digital Table The digital portion of the Channel Gain Table also referred to as Digital Table
39. handle counter One of the 16 bit timer counters of the board TC PCLK16 Pacer Clock 0 TC PCLK32 Pacer Clock 1 TC_BCLK Burst Clock TC_ADC_SCNT A D Sample counter TC_DCNT Delay Counter TC_ACNT About Counter TC_UTCO User TC 0 TC UTCI1 User TC 1 TC UTC2 User TC 2 mode Pointer to location to return counter mode count Pointer to location to return current count NOTE This is not the initial count or divisor of the counter There is no way to read initial count from a 8254 Timer Counter ReadUserInput7420 Syntax uintl ReadUserInput7420 RIDHANDLE hBoard DM7420 Data Acquisition Driver for Windows 95 98 NT 57 90 Description Read User Input Line 0 amp 1 Parameters hBoard device handle Return Value Bit 0 User input 0 state Bit 1 User input state All the other bits are zeros RemovelRQHandler7420 Syntax void RemoveIRQHandler7420 RTDHANDLE hBoard Description This routine is used to uninstall the IRQ handler function NOTE As a side effect this function disables all interrupt sources enabled when the interrupt handler was installed Parameters hBoard device handle ResetCGT7420 Syntax void ResetCGT7420 RTDHANDLE hBoard Description Reset the A D Channel Gain Table pointer to the beginning of the table After calling this function the next channel sampled is that of specified by the first entry in the Channel Gain Table NOTE Calling this function will cause a Channel
40. id SetUtcO0Clock7420 RTDHANDLE hBoard uintl6 src Description Select User Timer Counter 0 clock input Parameters hBoard device handle src CUTC0_8MHZ 0 Connect User T CO clock input to the SM on board crystal CUTCO EXT TC CLOCKI 1 Connect User T CO clock input to the External TC Clock 1 pin on the I O connector CUTCO EXT TC CLOCK2 2 Connect User T CO clock input to the External TC Clock 2 pin on the I O connector CUTCO_EXT_PCLK 3 Connect User T CO clock input to the External Pacer Clock pin on the I O connector SetUtc0Gate7420 Syntax void SetUtcOGate7420 RTDHANDLE hBoard uintl6 src Description User Timer Counter 0 Gate Select Parameters hBoard device handle srce GUTCO NOT GATED 0 Connect User T CO Gate to 5Volts let clock run GUTCO_GATED 1 Connect User T CO Gate to the ground stop clock 76 90 DM7420 Data Acquisition Driver for Windows 95 98 NT GUTCO EXT TC GATEI 2 Connect User T CO Gate to the External TC Gate 1 pin on the I O connector GUTCO EXT TC GATE2 3 Connect User T CO Gate to the External TC Gate 2 pin on the I O connector SetUtc1Clock7420 Syntax void SetUtc1Clock7420 RTDHANDLE hBoard uintl6 src Description User Timer Counter 1 Clock Select Parameters hBoard device handle src CUTC1 8MHZ 0 Connect User T C1 clock input to the SM on board crystal CUTC1 EXT TC CLOCKI 1 Connect User T C1 clock input to the External TC Cloc
41. iggering see Pre Post Triggering When the selected trigger occurs the A D Delay Counter starts the Pacer Clock but Pacer Clock is not yet enabled to drive the A D converter When Delay Counter counts down to zero Pacer Clock starts driving the A D converter PCLK START ETRIG GATED 0xF DM7420 Data Acquisition Driver for Windows 95 98 NT 69 90 Pacer Clock is started stopped by the External Trigger line In this mode the External Trigger line serves as the gate of the Pacer Clock Pacer Clock runs when line goes high and stops when the line goes low or vice versa depending on the programmed External Trigger polarity see SetEtrgPolarity7420 In this mode of operation programming Pacer Clock stop trigger SetPacerStop7420 has no effect SetPacerStop7420 Syntax void SetPacerStop7420 RTDHANDLE hBoard uintl6 src Description Select Pacer Clock Stop Trigger Parameters hBoard SIC 70 90 device handle PCLK STOP SOFTWARE 0x0 Pacer Clock is stopped by a call to StopPacer7420 PCLK STOP ETRIG 0x1 Pacer Clock stops when an External Trigger occurs A positive or negative going edge depending on the trigger polarity programmed by SetEtrgPolarity7420 on the external TRIGGER INPUT line will stop the Pacer Clock The pulse duration should be at least 100 nanoseconds PCLK STOP DIGITAL IT 0x2 Pacer Clock stops when a Digital Interrupt occurs PCLK_STOP_ACNT 0x3 Pacer Clock is stoppe
42. ion Driver for Windows 95 98 NT ISDINFifoEmpty7420 Syntax BOOL IsDINFifoEmpty7420 RIDHANDLE hBoard Description This routine checks to see if the High Speed Digital Input FIFO is empty Parameters hBoard device handle Return Value TRUE non zero if the High Speed Digital Input FIFO is empty ISDINFifoFull7420 Syntax BOOL IsDINFifoFull7420 RIDHANDLE hBoard Description This routine checks to see if the High Speed Digital Input FIFO is full Parameters hBoard device handle Return Value TRUE non zero if the High Speed Digital Input FIFO is full IsDINFifoHalfFull7420 Syntax BOOL IsDINFifoHalfFull7420 RTDHANDLE hBoard Description This routine checks to see if the High Speed Digital Input FIFO is half full Parameters hBoard device handle Return Value TRUE non zero if the High Speed Digital Input FIFO is half full DM7420 Data Acquisition Driver for Windows 95 98 NT 45 90 46 90 DM7420 Data Acquisition Driver for Windows 95 98 NT KickCounter7420 Syntax void KickCounter7420 RTDHANDLE hBoard int counter Description Results one clock signal to the designated counter After writing a new count value see Set8254Divisor7420 to a counter this function results in loading the initial count into the counter NOTE This feature is supported only for the sample counters Parameters hBoard device handle counter one of the following counters TC_ADC_SCNT A D Sa
43. k 1 pin on the I O connector CUTC1 EXT TC CLOCK2 2 Connect User T C1 clock input to the External TC Clock 2 pin on the I O connector CUTC1_EXT_PCLK 3 Connect User T C1 clock input to the External Pacer Clock pin on the I O connector CUTC1 UTCO OUT 4 Connect cascade User T C1 clock input to User T CO out CUTC1 DIN SIGNAL 5 Connect User T C1 clock input to the High Speed Digital Input sampling signal SetUtc1Gate7420 Syntax void SetUtcl1Gate7420 RTDHANDLE hBoard uintl6 src Description User Timer Counter 1 Gate Select Parameters hBoard device handle src GUTC1_NOT_GATED 0 Connect User T C1 Gate to 5 Volts let clock run DM7420 Data Acquisition Driver for Windows 95 98 NT 77 90 GUTC1 GATED 1 Connect User T C1 Gate to the ground stop clock GUTC1 EXT TC GATEI 2 Connect User T C1 Gate to the External TC Gate 1 pin on the I O connector GUTC1 EXT TC GATE2 3 Connect User T C1 Gate to the External TC Gate 2 pin on the I O connector GUTC1 UTCO OUT 4 Connect User T C1 Gate to User T C 0 out SetUtc2Clock7420 Syntax void SetUtc2Clock7420 RTDHANDLE hBoard uintl6 src Description User Timer Counter 2 Clock Select Parameters hBoard device handle Src CUTC2_8MHZ 0 Connect User T C2 clock input to the 8MHz on board crystal CUTC2 EXT TC CLOCKI 1 Connect User T C2 clock input to the External TC Clock 1 pin on the I O connector CUTC2_EX
44. ll start and sampling stops after nsamples At this point your sample buffer will contain the data you needed If you want to take more than 65 535 samples after the trigger you also need to do the following 3 Change About Counter setup to disable it stopping when it counts down to zero and install an interrupt handler on About Counter Countdown SetupAboutCounter7420 hBoard nsamples FALSE InstallCallbackIRQHandler7420 hBoard handler IRQM ABOUT CNT 6 Inthe About Counter interrupt handler count the Countdowns and enable About Counter to stop when the required number of samples has been taken EnableAcntStop7420 hBoard TRUE Q About Triggering About triggering scheme enables you to take samples around before and after an event trigger This is also called about triggering This scheme is very frequently used to take samples around an important event sampling Trigger This scheme is realized by using the About Counter Follow the steps below to set up for this scheme 1 Allocate a buffer which is big enough to hold samples to take before the event nsamples1 and after the event nsamples2 2 Set up the Pacer Clock to start from software and to stop on the desired trigger invent SetPacerStart7420 hBoard PCLK START SOFTWARE SetPacerStop7420 hBoard PCLK STOP A xxx 3 Initialize the About Counter for the number of samples you want to be collected after your trigger event SetupAboutCounter7420 hBo
45. m in the channel gain table you can make an entry twice to make sure that sufficient settling time has been allowed and an accurate reading has been taken Set the skip bit for the first entry so that it is ignored O For best results do not use the channel gain table when measuring steady state signals Use the single convert mode to step through the channels Interrupts DM7420 features a Priority Interrupt Controller with interrupt overrun protection Controller can receive interrupt request from up to 15 sources These 15 sources cover the most important internal signals of the board plus 3 external signals highest priority interrupt source comes first Q D A D FIFO Write Interrupt is generated when sample enters the A D FIFO This interrupt can be used for reading and processing samples real time CGT Reset Interrupt is generated when the Channel Gain Table recycles execution to the first table entry This interrupt can be used for reading and processing a burst of samples from different channels real time EI CGT Pause Interrupt is generated when Channel Gain Table execution is paused waiting for a new trigger About Counter Countdown Interrupt is generated when the About Counter counts down to zero This interrupt can be used to detect and react on the end of sampling when doing Pre Port Triggering Delay Counter Countdown Interrupt is generated when the Delay Counter counts down to zero This inter
46. mple Counter TC_ACNT About Counter TC_DCNT Delay Counter DM7420 Data Acquisition Driver for Windows 95 98 NT 47 90 48 90 DM7420 Data Acquisition Driver for Windows 95 98 NT LoadAcnt7420 Syntax void LoadAcnt7420 RTDHANDLE hBoard Description Load A D About Counter divisor After setting the About Counter divisor call this function to properly load the divisor Parameters hBoard device handle LoadAdcnt7420 Syntax void LoadAdcnt7420 RTDHANDLE hBoard Description Load A D Sample Counter divisor After setting the A D Sample Counter divisor call this function to properly load the divisor NOTE The output of the A D sample counter can be an interrupt source so at the end of the count down process an interrupt may be generated Parameters hBoard device handle LoadDent7420 Syntax void LoadDcnt7420 RTDHANDLE hBoard Description Load Delay Counter divisor After setting the Delay Counter divisor call this function to properly load the divisor Parameters hBoard device handle DM7420 Data Acquisition Driver for Windows 95 98 NT 49 90 50 90 DM7420 Data Acquisition Driver for Windows 95 98 NT OpenBoard7420 Syntax BOOL OpenBoard7420 LONG DeviceNumber BOOL LoadDevice LPSTR szBuf BoardConfig boardconfig Description This routine is used to open board This function must be called before any API function call At the end of the application program the board mus
47. mple uses the first installed DM7420 Channel Gain Latch is programmed for AIN1 5Volts bipolar single ended A D converter is programmed for software triggered conversions When pressing the Start button an A D conversion is initiated and the sample is displayed on screen as Voltage WTIMERS GUI MFC Example Example on programming the User Timer Counters 88 90 DM7420 Data Acquisition Driver for Windows 95 98 NT This example counts seconds real time This example uses the first installed DM7420 User Timer Counter 0 and 1 are cascaded Counter 0 is programmed for 200 Hertz When pressing the Start button a Windows timer is programmed for 200 msec to provide the main program loop In every iteration User Timer Counter count is read back and converted to seconds DM7420 Data Acquisition Driver for Windows 95 98 NT 89 90 90 90 DM7420 Data Acquisition Driver for Windows 95 98 NT
48. nd example programs The setup program automatically detects your operating system Windows 95 98 or NT and installs the appropriate files on your PC After starting the setup please follow the instructions on the screen to install the programs You can select the directory where to install the files The setup also adds to the Start menu under the Programs folder of your Windows system the Real Time Devices USA folder It contains shortcuts to the example programs and the readme txt file The example programs will be installed in the target directory under the Examples folder This folder contains the example program sources for the DM7420 board and the project files for Microsoft Visual C users to rebuild the programs The example programs are compiled with the Microsoft Visual C ver 5 0 In case of different version of Visual C is installed on your PC please rebuild the executable files Uninstallation you can uninstall the DM7420 driver and example programs under the Control panel with the Add Remove Programs tool DM7420 Data Acquisition Driver for Windows 95 98 NT 5 90 6 90 DM7420 Data Acquisition Driver for Windows 95 98 NT The DM7420 Board Driver The RTD s DM7420 board driver handles the hardware through the BlueWater s WinRT driver The WinRT driver provides the low level access to the board and the RTD s Dm7420 dll provides the device API for the programmers and communicates with the
49. nned through with each selected A D Conversion Signal pulse starting a conversion at the channel and gain specified in the current table entry Before starting a conversion sequence Channel Gain Table you need to load the table with the desired data Then make sure that the Channel Gain Table is enabled by the function EnableCGT7420 This enables the A D portion of the Channel Gain Table If you are using the Digital Table as well you must also enable this using the function EnableCGTDigital7420 Each rising edge of selected A D Conversion Signal starts a conversion using the current Channel Gain data and then increments to the next position in the table When the last entry is reached the next pulse starts the table over again Q Programmable Burst In this mode a single trigger initiates a scan of the entire Channel Gain Table Before starting a burst of the Channel Gain Table you need to load the table with the desired data Then enable the Channel Gain Table by EnableCGT7420 This enables the A D portion of the channel gain table If you are using the Digital Table as well you must also call EnableCGTDigital7420 Burst is used when you want one sample from a specified number of channels for each trigger The burst trigger starts the Burst Clock and the Burst Clock initiates each conversion At high speeds the burst mode emulates simultaneous sampling of multiple input channels For time critical simultaneous sampling applications a simult
50. oard Windows 95 98 NT driver has designed for programmers who write Windows based application programs with using the RTD s DM7420 board The driver provides an Application Programming Interface with a lot of function calls to perform all the data acquisition tasks of the board users The board driver based on the BlueWater System s WinRT device driver kit There are example programs to demonstrate the various board features and the usage of the driver API The example programs are written in Microsoft Visual C ver 5 0 Installation Installation of the Driver and Example Programs Before installing the driver and example program files you need to install the DM7420 board in your PC Please follow the instructions of the manufacturer how to install the board in a computer The DM7420 board is a data acquisition board with PCI bus The Windows 95 98 operating system and the Windows NT handles differently the plug and play features of a PCI boards so the installation of the driver is different Under the Windows 95 98 operating system after the first installation of the DM7420 board the system detects the new board and asks for the driver for it On the installation diskette 0 can be found the low level driver files to perform the first setup of the board Under Windows NT you do not need the installation diskette 0 On the installation diskette I you can found the Setup exe program which installs on your PC the DM7420 board driver a
51. ode N A set to zero compare N A set to zero clock N A set to zero irq N A set to zero SetUout0Source7420 SetUout1Source7420 Syntax void SetUout0Source7420 RTDHANDLE hBoard uintl6 src void SetUoutlSource7420 RTDHANDLE hBoard uintl6 src Description Select User Output 0 1 signal 72 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Parameters hBoard device handle src 0x0 A D Conversion Signal 0x1 Not used 0x2 Not used 0x3 Software Programmable by WriteUserOutput7420 Use UOUT_XXXX for argument src SetupAboutCounter7420 Syntax void SetupAboutCounter7420 RTDHANDLE hBoard uintl6 samples I uintl6 enable Description Program the about counter The function programs the rate and enables or disables the about counter NOTE This function is a short for the following calls Set8254Mo0de7420 hBoard TC ACNT M8254 RATE GENERATOR Set8254Divisor7420 hBoard TC ACNT samples KickCounter7420 hBoard TC ACNT EnableAcntStop7420 hBoard enable Parameters hBoard device handle samples initial count enable 0 stop disabled 1 stop enable SetupBurst7420 Syntax void SetupBurst7420 RTDHANDLE hBoard uintl6 start float rate Description Setup the burst clock See the SetBurstStart7420 and the SetBurstRate7420 functions NOTE This function is a short for the following calls SetBurstStart7420 hBoard start SetBurstR
52. on Select External Trigger polarity NOTE External Trigger polarity also defines the behavior of the Pacer Clock in Gated mode Parameters hBoard device handle polarity 0x0 External Trigger occurs on the positive edge of the External Trigger line 0x1 External Trigger occurs on the negative edge of the External Trigger line SetHdinStart7420 Syntax void SetHdinStart7420 RTDHANDLE hBoard uintl6 src Description Select sampling signal for High Speed Digital Input DM7420 Data Acquisition Driver for Windows 95 98 NT 65 90 Parameters hBoard src SetITMask7420 Syntax device handle 0x0 Software Trigger Port is sampled when StartHDin7420 is called 0x1 A D Conversion Signal Port is sampled in synchrony with the Analog Input 0x2 User TC out 0 0x3 User TC out I Ox4 User TC out 2 Port is sampled when User T C 0 1 2 counts down to zero 0x5 External Pacer Clock Port is sampled by the External Pacer Clock 0x6 External Trigger Port is sampled when an External Trigger occurs Use HDIN XXXX for argument src void SetITMask7420 RTDHANDLE hBoard uintl6 mask Description Write Interrupt Enable Mask Register Parameters hBoard mask 66 90 device handle IT source bit mask Bit 0 source is disabled bit 1 source is enabled IRQM_ADC_FIFO_WRITE 0x0001 Enable generating interrupt when sample entered to the A D FIFO IRQM CGT RESET 0x0002
53. ort 0 by connecting a trigger pulse through the External Pacer Clock pin at the External I O Connector This data can be read from the Compare Register with GetDIOOCompare Value7420 18 90 DM7420 Data Acquisition Driver for Windows 95 98 NT DM7420 Data Acquisition Driver for Windows 95 98 NT 19 90 Driver API Function Groups Driver Initialization Functions OpenBoard7420 CloseBoard7420 GetErrorStatus7420 General Board Control Functions InitBoard7420 Clear A1llI07420 FIFO Manipulation GetFifoStatus7420 IsADFIFOEmpty 7420 IsADFifoHalfFull7420 IsADFifoFull7420 IsDINFifoEmpty7420 IsDINFifoHalfFull7420 IsDINFifoFull7420 ClearDinFifo7420 ClearADFIFO7420 ReadADData7420 ReadADDataWithMarker7420 GetAutoIncDataByte7420 GetAutoIncDataWord7420 ReadDinFifo7420 A D Converter StartConversion7420 SetConversionSelect7420 Channel Gain Table Manipulation WriteCGTAnalog7420 WriteCGTLatch7420 WriteCGTDigital7420 EnableCGT7420 EnableCGTDigital7420 EnableCGTPause7420 ResetCGT7420 ClearCGT7420 SetupCgtRow7420 SetChannelGain7420 Pacer Clock Handling StartPacer7420 StopPacer7420 SetPacerStart7420 SetPacerStop7420 SetPacerRepeat7420 DM7420 Data Acquisition Driver for Windows 95 98 NT 21 90 SetPclkSize7420 SetPacerSource7420 SetPacerRate7420 SetPacerClock7420 Burst Clock Handling StartBurst7420 SetBurstStart7420 SetBurstRate7420 SetupBurst7420 Delay Counter Functions LoadDent7420 SetupDelayCounter7420
54. ot half empty Bit 10 0x0400 ADC FIFO not full Bit 11 0x0800 0 reserved Bit 12 0x1000 DIN FIFO not empty Bit 13 0x2000 DIN FIFO not half empty Bit 14 0x4000 DIN FIFO not full Bit 15 0x8000 0 reserved See FS XX XX symbolic constants GetIRQCounter7420 Syntax void Get IRQCounter7420 RTDHANDLE hBoard IRQSetup irqsetup Description Return the counter incremented by the interrupt handler The counter is an 8 bit counter Parameters hBoard device handle irqsetup structure to return Parameters to caller DM7420 Data Acquisition Driver for Windows 95 98 NT 39 90 GetITStatus7420 Syntax uintl GetITStatus7420 RTDHANDLE hBoard Description Read Interrupt Status Register Parameters hBoard device handle Return Value Return a mask of interrupt sources which have a pending interrupt request bit 0 inactive bit 1 active Bit 0 0x0001 ADC FIFO Write Bit 1 0x0002 Reset CGT Bit 2 0x0004 reserved Bit 3 0x0008 Pause CGT Bit 4 0x0010 ADC FIFO half full Bit 5 0x0020 ADC FIFO full Bit 6 0x0040 ADC Sample Counter Bit 7 0x0080 Not used Bit 8 0x0100 Not used Bit 9 0x0200 User TC1 out Bit 10 0x0400 User TC1 out inverted Bit 11 0x0800 User TC2 out Bit 12 0x1000 Digital Interrupt Bit 13 0x2000 External Interrupt Bit 14 0x4000 External Trigger rising edge Bit 15 0x8000 External Trigger falling edge GetTimerStatus7420 Syntax uintl6 GetTimerSt
55. r function will run in a separate thread after the completion of the interrupt service routine Parameters hBoard device handle isrT handler user callback function mask IT sources to enable InstallCounterIRQHandler7420 Syntax void InstallCounterIRQHandler7420 RTDHANDLE hBoard IRQSetup irqsetup uintl6 mask Description This routine is used to install IRQ handler function This interrupt handler function increments an 8 bit counter on every IRQ The value of the counter can read by the GetIRQCounter7420 function DM7420 Data Acquisition Driver for Windows 95 98 NT 43 90 Parameters hBoard device handle irqsetup return Parameters to caller mask IT sources to enable ISADFifoEmpty7420 Syntax uintl6 IsADFifoEmpty7420 RTDHANDLE hBoard Description This routine checks to see if the A D FIFO is empty Parameters hBoard device handle Return Value TRUE non zero if the A D FIFO is empty ISADFifoFull7420 Syntax BOOL IsADFifoFull7420 RTDHANDLE hBoard Description This routine checks to see if the A D FIFO is full Parameters hBoard device handle Return Value TRUE non zero if the A D FIFO is full IsADFifoHalfFull7420 Syntax BOOL IsADFifoHalfFull7420 RTDHANDLE hBoard Description This routine checks to see if the A D FIFO is half full Parameters hBoard device handle Return Value TRUE non zero if the A D FIFO is half full 44 90 DM7420 Data Acquisit
56. rupt Service Routine since you can not do that under Windows NT Your handler is an ordinary routine which is called by the real Interrupt Service Routine implemented by the DM7420 driver The driver s Interrupt Service Routine schedules your interrupt handler for execution as a separate thread acknowledges the interrupt to the board s interrupt controller and returns After returning the scheduled thread starts executing your interrupt handler Pre and Post Triggering DM7420 offers various triggers for pre post about triggering The triggering mechanism built around the Pacer Burst Clock circuitry lets you implement various triggering schemes DU Pre Triggering Pre triggering scheme enables you to start sampling with some delay after an event trigger DM7420 Data Acquisition Driver for Windows 95 98 NT 15 90 sampling Start Trigger This scheme can be useful when you do not want the first couple of samples after the important event This can be the case when you know that these samples are noisy or meaningless because of settling issues This scheme is realized by using the Delay Counter Follow the steps below to set up for this scheme 1 Set up the Pacer Clock to start delayed on the desired event SetPacerStart7420 hBoard PCLK START D xxx 2 Initialize the Delay Counter for the required number of samples to wait Delay Counter counts at the rate of the Pacer Clock SetupDelayCounter7420 hBoard samples 3
57. rupt can be used to detect and react on the actual start of sampling when doing Pre Port Triggering A D Sample Counter Countdown Interrupt is generated when the A D Sample Counter counts down to zero This interrupt can be used to count more than 65535 samples by counting the turnovers of the Sample Counter EI User Timer Counter 1 Out User Timer Counter 1 Out inverted User Timer Counter 2 Out Interrupt is generated on the ticks of User T C1 1 e when the counter counts down to Zero This interrupt gives you a general purpose means of measuring real time frequency or counting events It is also intended to use for Pulse output generation Digital Interrupt Interrupt is generated when the Advanced Digital Trigger signals a Digital Interrupt This interrupt can be used to detect and react on certain patterns on Digital Input 14 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Port 0 EI Q External Interrupt Interrupt is generated on the rising edge of the External Interrupt pin of the I O connector This interrupt is intended for exporting events from an external device O External Trigger rising edge Q External Trigger falling edge Interrupt is generated on a rising falling edge of the External Trigger pin This interrupt is intended for the Gated Mode operation of the Pacer Clock Because of the several interrupt sources on the board a Priority Interrupt Controller was built to assure even usag
58. s for A D Conversion Trigger SetConversion7420 Burst Clock Start Trigger SetBurstStart7420 Pacer Clock Start Stop Trigger SetPacerStart7420 SetPacerStop7420 and creating different Channel Gain Tables you have innumerable sampling scenarios The following bullets try to enumerate only the most frequently used measurement setups Q Single Conversion In this mode a single channel is sampled whenever StartConversion7420 is called The Channel Gain Latch see WriteCGTLatch7420 specifies the channel to sample This is the easiest scenario of all It can be used in a variety of applications such as sample every time a key is pressed on the keyboard sample with each iteration of a loop or watch the system clock and sample every five seconds Q Multiple Conversions In this mode conversions are continuously performed at the rate of the Pacer Clock or other selected A D Conversion Signal rate The pacer clock can be internal or external The maximum rate supported by the board is 1 25MHz The Pacer Clock can be turned on and off using any of the start and stop triggering modes using the functions SetPacerStart7420 and SetPacerStop7420 If you use the internal pacer clock you must program it to run at the desired rate SetupPacerClock7420 This mode is ideal for filling arrays acquiring data for a specified period and taking a specified number of samples Q Random Channel Scan In this mode the Channel Gain Table is incrementally sca
59. sistor is needed to ground the AINSENSE signal To configure an NRSE analog input connect the high side of the input signal to the selected analog input channel AIN1 AIN16 and connect the low side to the AINSENSE pin of the I O connector If you use channels AIN9 AIN16 switch the appropriate SW1 and SW2 dips off See Hardware Manual for more Differential DIFF Se Diff 1 NRSE x This mode can be useful when the shielding of the signal is important In differential mode you use two analog input channels of the board for an analog input AINx and AINx 8 also referred to as AINx and AINx can be used in couple for a differential analog input This way you may have up to 8 differential analog inputs For this input type the reference signal of Instrumentation Amplifier is the AIN signal To configure an NRSE analog input connect the high side of the analog input to the selected analog input channel AIN1 AIN8 and connect the low side to the corresponding AIN pin AIN1 AIN9 AIN8 AIN16 See Hardware Manual for more Pause Pause Bit If this bit is set and pausing is enabled by the EnableCGTPause7420 function execution of the Channel Gain Table stops after executing this entry Execution is resumed with the next CGT entry when the programmed Pacer Clock start trigger occurs EXAMPLE Pause Bit can be used when you have two sequence of entries each to be NOTE executed on a different event trigger Suppose
60. t be closed with the CloseBoard7420 function Parameters DeviceNumber Device number to load Installed devices are numbered from 0 in the system registry LoadDevice Load not load the WinRT driver szBuf message buffer to return error message boardconfig Pointer to a BoardConfig structure to return configuration information about the board Use this argument if you need to know the Operating System resources allocated to the board Pass NULL for this argument if you do not need this information DM7420 Data Acquisition Driver for Windows 95 98 NT 51 90 52 90 DM7420 Data Acquisition Driver for Windows 95 98 NT PollDIO07420 Syntax void PollDIO07420 RTDHANDLE hBoard uint8 direction uint8 mask uint8 mode uint8 compare uint8 clock uint8 irg uint8 itstatus Description Return Digital I O Port 0 status Parameters hBoard direction mask mode compare clock irq itstatus device handle Returns the programmed direction mask for the 8 I O lines see GetDIOODirection7420 Bit 0 line is programmed for input Bit I line is programmed for output Returns the Digital Interrupt mask for Port 0 I O lines see GetDIOOMask7420 Bit 0 line is disabled to take part in Digital Interrupt generation Bit I line is enabled to take part in Digital Interrupt generation Returns Advanced Digital Trigger mode see GetDIO0CompareMode 7420 0 Event mode 1
61. tStart7420 Parameters hBoard device handle StartHdin7420 Syntax void StartHdin7420 RTDHANDLE hBoard Description Generate a High Speed Digital Input start trigger NOTE This function is needed and has only effect if High Speed Digital Input is programmed for software start see SetHdinStart7420 DM7420 Data Acquisition Driver for Windows 95 98 NT 79 90 Parameters hBoard device handle StartPacer7420 Syntax void StartPacer7420 RTDHANDLE hBoard Description Generate a software Pacer Clock start trigger NOTE This function is needed and has only effect if Pacer Clock is programmed for software start see SetPacerStart7420 Parameters hBoard device handle StopPacer7420 Syntax void StopPacer7420 RTDHANDLE hBoard Description Generate a software Pacer Clock stop trigger NOTE This function is needed and has only effect if Pacer Clock is programmed for software stop see SetPacerStop7420 Parameters hBoard device handle 80 90 DM7420 Data Acquisition Driver for Windows 95 98 NT WriteCGTAnalog7420 Syntax void WriteCGTAnalog7420 RTDHANDLE hBoard uintl6 entry Description Write entry to the Analog part of the Channel Gain Table NOTE If you have cleared the Channel Gain Table by the ClearCGT7420 function the first byte written will be placed in the first entry of the table The second byte will be placed in the second entry and so on If you are
62. terrupts Parameters hBoard device handle mask mask of interrupt sources for which to acknowledge interrupts DO 0x0001 ADC FIFO Write D1 0x0002 Reset CGT D2 0x0004 reserved D3 0x0008 Pause CGT D4 0x0010 ADC FIFO half full D5 0x0020 ADC FIFO full D6 0x0040 ADC Sample Counter D7 0x0080 Not used D8 0x0100 Not used D9 0x0200 User TC1 out D10 0x0400 User TC1 out inverted D11 0x0800 User TC2 out D12 0x1000 Digital Interrupt D13 0x2000 External Interrupt D14 0x4000 External Trigger rising edge D15 0x8000 External Trigger falling edge ClearlTOverrun7420 Syntax void ClearITOverrun7420 RTDHANDLE hBoard Description Clear Interrupt Overrun Register The Interrupt Overrun Register is for detecting interrupt overrun conditions If an interrupt occurs from a source and an other interrupt occurs from that source before the first interrupt is acknowledged the appropriate bit in the Interrupt Overrun Register goes to I indicating overrun DM7420 Data Acquisition Driver for Windows 95 98 NT 29 90 NOTE This function is automatically called on every interrupt if you install an interrupt handler Parameters hBoard device handle CloseBoard7420 Syntax BOOL CloseBoard7420 LONG DeviceNumber LPSTR szBuf Description This routine is used to close a board Call this function when you finished to use a board CloseBoard7420 releases no longer needed system resources and the DM7420 itself
63. that CGT is driven by the Pacer Clock and the Pacer Clock is started on the External Trigger The External Trigger comes from a device whose pulses indicate two different events Odd pulses indicate an event on which you want to react by sampling AIN1 and AIN2 on even pulses you want to sample AIN3 AIN4 and AINS In this case you would create a 5 entry CGT Entry 1 AIN1 Pause Bit 0 Entry 2 AIN2 Pause Bit 1 Entry 3 AIN3 Pause Bit 0 Entry 4 AIN4 Pause Bit 0 Entry 5 AINS Pause Bit 1 In this case the first pulse on the External Trigger line starts executing the CGT at the rate of the Pacer Clock After executing the first two entries execution stops and is waiting for the next External Trigger pulse The second pulse resumes execution and entries 3 4 and 5 are executed at the rate of the Pacer Clock Execution pauses again after executing entry 5 A third External trigger pulse continues execution with entry 1 and so on When the Channel Gain Latch is used or in burst mode Pause Bit is ignored DM7420 Data Acquisition Driver for Windows 95 98 NT 11 90 Skip Skip Bit When the Skip Bit is set the entry is skipped which means that the A D conversion is performed but the resulting sample is not written into the A D FIFO This feature provides a way to sample multiple channels at different rates without saving unwanted data EXAMPLE In this example we want to sample AIN1 in every second and AIN4 in
64. tion Program Port 0 compare value Parameters hBoard device handle compare See Also Advanced Digital Trigger SetDIOODirection7420 Syntax void SetDIOODirection7420 RTDHANDLE hBoard uint8 direction Description Program Port 0 direction bit programmable Parameters hBoard device handle direction bit 0 input bit 1 output SetDIOOMask7420 Syntax void SetDIOOMask7420 RTDHANDLE hBoard uint8 mask Description Program Digital Interrupt mask for Port 0 I O lines Parameters hBoard device handle mask bit mask to enable disable I O lines taking part in Digital Interrupt generation See Also Advanced Digital Trigger SetDIO1Direction7420 Syntax void SetDIOlDirection7420 RTDHANDLE hBoard uint8 direction Description Program Port 1 direction byte programmable 64 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Parameters hBoard device handle direction 0 input 1 output SetEintPolarity7420 Syntax void SetEintPolarity7420 RTDHANDLE hBoard uint16 polarity Description Select External Interrupt polarity Parameters hBoard device handle polarity 0x0 Interrupts are generated on the positive edge of the External Interrupt line Ox1 Interrupts are generated on the negative edge of the External Interrupt line SetEtrgPolarity7420 Syntax void SetEtrgPolarity7420 RTDHANDLE hBoard uint16 polarity Descripti
65. to its first entry Parameters hBoard device handle src Use BCLK START XXXX for argument erc BCLK START SOFTWARE 0x0 Calling the StartBurst7420 function starts Burst Clock BCLK START PCLK 0x1 Burst Clock is started on every Pacer Clock tick BCLK START ETRIG 0x2 Burst Clock is started by the External Trigger line BCLK START DIGITAL IT 0x3 Burst Clock is started when a Digital Interrupt occurs BCLK START SBUS0 0x4 BCLK START SBUSI1 0x5 BCLK START SBUS2 0x6 Burst Clock is started by a rising edge on Synchron Bus line 0 1 2 See Also Channel Gain Circuitry DM7420 Data Acquisition Driver for Windows 95 98 NT 61 90 SetChannelGain7420 Syntax void SetChannelGain7420 RTDHANDLE hBoard uint16 Channel uintl6 Gain uintl6 Range uintl6 Se Diff Description This routine loads the channel gain latch Parameters hBoard device handle Channel One of the 16 Analog Input channels 0 AIN1 1 AIN2 etc Gain Gain value to apply on the Analog Input channel Valid gains are 1 2 4 8 16 32 64 128 Range Analog Input range Valid values are 0 to 5 Volts 0 to 10 Volts 5 to 5 Volts 10 to 10 Volts Se_Diff Analog Input channel type Single Ended Differential SetConversionSelect7420 Syntax void SetConversionSelect7420 RTDHANDLE hBoard uintl6 Select Description Select A D Conversion start signal Parameters hBoard device handle Select ADC_START_SOFTWARE 0x0 On
66. uitry EnableCGT7420 EnableCGTPause7420 Syntax void EnableCGTPause7420 RTDHANDLE hBoard uintl6 enable Description Enable disable using the Channel Gain Table Pause Bit NOTE Set the Pause Bit if you want to stop an entry in the table and wait for the next trigger In burst mode the pause bit is ignored Parameters hBoard device handle enable FALSE 0 Disable interpreting CGT Pause Bit TRUE 1 Enable interpreting CGT Pause Bit See Also Channel Gain Circuitry EnableDIOOIrq7420 Syntax void EnableDIO0Irq7420 RTDHANDLE hBoard BOOL enable 32 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Description Enable disable Bit Programmable Digital I O to generate interrupts Parameters hBoard device handle enable FALSE 0 disable TRUE 1 enable See Also Advanced Digital Trigger DM7420 Data Acquisition Driver for Windows 95 98 NT 33 90 34 90 DM7420 Data Acquisition Driver for Windows 95 98 NT Get8254Count7420 Syntax uintl6 Get8254Count7420 RTDHANDLE hBoard int counter Description Read current counter value of a 8254 Timer Counter Parameters hBoard device handle counter One of the 16 bit timer counters of the board Use TC_XXXX for argument counter Get8254Mode7420 Syntax uint8 Get8254Mode7420 RTDHANDLE hBoard int counter Description Read back programmed operation mode of a 8254 Timer Counter Parameters hBoard device handle
67. with Pacer Clock 0 SetPort0Direction7420 Syntax void SetPortO0Direction7420 RTDHANDLE hBoard uint8 direction uint8 mask uint8 mode uint8 compare uint8 clock BOOL irq Description Configure Digital I O Port 0 NOTE This function is a short for the following calls SetDIOO0Direction7420 hBoard direction SetDIO0Mask7420 hBoard mask SetDIO0CompareMode7420 hBoard mode SetDIO0CompareValue7420 hBoard compare DM7420 Data Acquisition Driver for Windows 95 98 NT 71 90 SetDIOOClock7420 hBoard clock EnableDIO0Irq7420 hBoard irq Parameters hBoard device handle direction 8 bit mask specifying the direction of the individual lines see SetDIOODirection7420 mask Digital Interrupt generation mask see SetDIOOMask7420 mode Triggering Mode see SetDIOOCompareMode7420 compare Compare value for Match mode see SetDIOOCompareValue7420 clock Clock for Digital Triggering see SetDIOOCLock7420 irq Enable disable Digital Interrupt generation see EnableDIOOIrq7420 SetPort1 Direction7420 Syntax void SetPortlDirection7420 RTDHANDLE hBoard uint8 direction uint8 mask uint8 mode uint8 compare uint8 clock BOOL irq Description Configure Digital I O Port 0 NOTE This function is a short for the following calls SetDIO1Direction7420 hBoard direction Parameters hBoard device handle direction port direction see SetDIO1 Direction7420 mask N A set to zero m

DM7420 Data Acquisition Driver for Windows 95/98/NT User`s Manual

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