(old board) Manual v1.1 - Diamond Systems Corporation
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1. 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 32 Function 9 Return Current Analog Settings Outputs d 1 Current low channel no setting O 15 d 2 Current high channel setting 0 15 d 3 Current A D gain code Code Gain 0 1 1 2 2 4 3 8 d 4 Current A D range code Code Range 0 5V 1 10V 2 0 10V d 5 Current D A polarity setting 0 bipolar 1 unipolar Function 9 returns the current settings programmed into the board Function 20 Single D A conversion Inputs d 1 D A code 0 4095 d 2 Channel 0 3 Function 20 programs the selected D A channel with the indicated code See the formulas in Section 10 1 on page 22 for calculating the D A code needed to produce the desired output voltage Note that the unipolar bipolar setting is not provided here since if it is changed then all four channels are affected Therefore the D A unipolar bipolar setting should be done only once at program startup during the board initialization function Function 0 Function 21 Simultaneous D A output on 4 channels Inputs d 1 D A code for channel 0 O 4095 d 2 D A code for channel 1 0 4095 d 3 D A code for channel 2 0 4095 d 4 D A code for channel 3 0 4095 This function updates all four D A channels simultaneously with the selected codes See the formulas in Section 10 1 on page 22 for calculating the D A code needed to produce the desired output voltage 1998 Diamo2. For all analog input measurements single ended inputs are assumed jumpers in J4 are in the top position 12 1 Gain Amplifier Output Offset Adjust Connect channel 0 to analog ground wire J3 pin 17 to J3 pin 16 Select channel 0 as the current input channel write 0 to base 2 Select a gain of 1 write 0 to base 11 Connect the voltmeter to test point 1 and adjust R6 until the meter reads 0 000V 12 2 Gain Amplifier Input Offset Adjust Connect channel 0 to analog ground wire J3 pin 17 to J3 pin 16 Select channel 0 as the current input channel write 0 to base 2 Select a gain of 8 write to base 11 Connect the voltmeter to test point 1 and adjust R7 until the meter reads 0 000V Note Steps 12 1 and 12 2 affect each other so several iterations may be necessary to converge on a measurement for both adjustments 12 3 A D 5V Range Gain Adjust Jumper on J5 needs to be installed over the middle and left pins Connect the voltmeter to the reference output pin the I O header J3 18 and measure the voltage It will be in the range 5 000V 2 5mV Connect channel 0 to the output reference wire J3 pin 18 to J3 pin 16 Select channel 0 as the current input channel write 0 to base 2 Select a gain of 1 and 5V range write 0 to base 11 Connect the voltmeter to test point 2 and adjust R5 until the meter reads 2 times the reference voltage measured above approximately 10 000V 1998 Diamon
3. d 3 44 Base address see list below Interrupt level 2 7 default is 5 DMA level 1 or 3 default is 3 D A polarity setting 0 bipolar 1 2 unipolar Function 0 must be the first dmm16 function call in any program using the driver It gives the driver information about Diamond MM 16 for use in subsequent function calls Base Address Hex 100 140 180 1C0 200 240 280 2C0 300 340 380 1998 Diamond Systems Corp Decimal 256 320 384 448 512 576 640 704 768 Default 832 896 960 Pin Header J8 Configuration 9 Installed Installed Installed Installed Open Open Open Open Open Open Open Open 8 Open Open Open Open Installed Installed Installed Installed Open Open Open Open 7 Installed Installed Open Open Installed Installed Open Open Installed Installed Open Open 6 Installed Open Installed Open Installed Open Installed Open Installed Open Installed Open Diamond MM 16 User Manual V1 1 Page 29 Function 1 Single A D conversion Inputs _ d 2 Channel no 0 15 d 3 Gain code Code Gain 0 1 1 2 2 4 3 8 d 4 Full scale range code Code Range 0 5V 1 10V 2 0 10V Output d 1 A D code 32768 32767 Function 1 performs a single A D conversion on the selected channel The result is returned in d 1 Note that the value is always twos complement even though the input range may be set for unipolar voltages See Sect
4. 0 0 No external gate on external A D clock 1 External gate enabled on external A D clock d 9 Gain code see table on previous page d 10 Full scale range code see table on previous page Functions 3 and 4 install an interrupt routine to acquire data in background mode and store it in a memory buffer Function 5 uses the PC s DMA controller for high speed transfers from the A D to PC memory In C the buffer can be an integer array using the DSC functions get segment array and get offset array for d 2 d 3 see below Miscellaneous Functions The operation type indicator d 4 determines how the memory buffer is used If d 4 0 then d 1 conversions are performed and then interrupts DMA transfers stop If d 4 1 then after d 1 conversions the internal buffer pointer is reset to the start and future interrupts DMA requests overwrite the buffer with new data Thus the most recent d 1 conversions are always in memory and the current position in the buffer can be acquired by using Function 81 below The sequence of operations is as follows The A D clock source selected with d 5 internal or external generates A D conversion on the current channel and simultaneously increments the channel register to the next channel in the range selected by d 6 and d 7 When the A D conversion is complete the data is transferred to the PC via either interrupt routine Functions 3 and 4 or DMA cycle Function 5 Note tha
5. Counter 0 input source 1 Input to Counter 0 is a 100kHz on board reference frequency derived from the 10MHz oscillator INO pin 29 on the I O header gates this signal When it is high default the 100kHz signal runs When it is low the 100kHz signal is stopped 0 Input to Counter 0 is an inverted polarity copy of INO INO is connected to a 10KQ pull up resistor Counters 1 and 2 gate control 1 Counters 1 and 2 are gated by DIO pin 48 on the I O header When DIO is low PRIOR TO THE START OF DMA CONVERSIONS A D conversions will not occur until it is brought high DIO is connected to 10 pullup resistor 0 Counters 1 and 2 run freely with no gating 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 13 Base 11 Write Analog Configuration Register DABU D A bipolar unipolar setting 0 bipolar 1 unipolar RANGE 5V or 10V A D positive full scale voltage ADBU A D bipolar unipolar setting 0 bipolar 1 unipolar The table below lists the effects of the various combinations of ADBU and RANGE RANGE _ADBU A D full scale range 0 0 5V 0 1 Invalid setting 1 0 10V 1 1 0 10V G1 0 A D gain setting Gi G0 Gain 0 0 1 0 1 2 1 0 4 1 1 8 The gain setting is the ratio between the A D full scale range and the effective input signal range For example if the A D full scale range is 0 10V a gain setting of 2 creates an input signal range of 0 5V and a gain setting of 4 creates an i
6. The interface is as follows In C dmm16 d In Basic CALL DMM16 5 05 0 where dmm16 is the function name f f is an integer containing the function number and d or D is an integer array size 17 elements containing parameters and return data specific to the function number For GW BASIC programs you must load the driver into free memory at the start of your program as follows 10 DEF SEG amp H4000 example of free area can be changed 20 BLOAD DMM16 BIN 0 load driver at address 40000 hex segment 4000 offset 0 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 27 15 DRIVER FUNCTION LIST In the descriptions below Input means data passed to the function and Output means data returned from the function Function 0 is an initializing function and must be the first DMM16 call in any program The functions are grouped by type 0 is initialization 1 19 are analog input 20 39 are analog output 40 59 are digital and 80 99 are auxiliary Not all function numbers are assigned The current DMM16 functions are No Function Description Page 0 Initialize board and driver 29 1 Perform single A D conversion 30 2 Perform A D scan up to 16 channels 30 3 Perform interrupt driven A D conversions 31 4 Perform interrupt driven A D scans 31 5 Perform DMA driven A D conversions fastest possible rates 31 9 Return current analog I O settings 33 20 Perform D A conversion on one channel 33
7. value written does not matter Writing to Base 0 will start an A D conversion even if the board is set up for interrupt DMA or external trigger mode 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 9 Base 1 Definitions DA 0 D A data bits 7 0 for the channel currently being accessed This register is a holding register Writing to it does not affect any D A channel until the MSB is written When the MSB is written see below Base 4 through Base 7 the value written to that register along with the value written to this register are simultaneously written to the D A chip s load register for the selected channel A final read operation from Base 7 is required to update the D A with the new 12 bit value This final read operation is provided in order to enable simultaneous update of all 4 channels at once Base 2 Read Write A D Channel Register Definitions HIGH3 O High channel of channel scan range ranges from 0 to 15 in single ended mode 0 7 in differential mode LOWS 0 Low channel of channel scan range ranges from 0 to 15 in single ended mode 0 7 in differential mode Note the high channel does not need to be higher than the low channel for example LOW 8 and HIGH 2 are valid settings Base 3 Write Digital Output Port Bit No Name These pins correspond directly to the same named pins on I O connector J3 pins 33 40 On power
8. 21 Perform D A conversion on all four channels 33 41 Digital byte input 34 42 Digital byte output 34 45 Bit input 34 46 Bit set reset 34 47 Interrupt driven digital input 35 48 Interrupt driven digital output 35 61 Program counter timer 36 62 Counter timer readback 37 63 Direct counter timer access 37 80 Data transfer between array and memory buffer for digital I O operations 38 81 Interrupt DMA operation statistics 39 82 Halt resume interrupt DMA operation 39 16 ERROR CODE LIST An Error code is returned in d 0 after each function call Generally all arguments are checked for validity before the function executes However certain arguments such as pointer values are not checked so caution is advised when using pointers since an invalid pointer can corrupt memory or crash the system when the program attempts to write data to the referenced memory location Code Error 0 No error function executed properly 1 12 Value n in array d has an invalid value check specifications 20 Invalid function number 21 Driver not initialized must use Function O first 22 Hardware error possible incorrect base address setting 23 Background operation cannot start because another one is already running 24 Cannot resume background operation because none was running suspended 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 28 17 DRIVER FUNCTION DESCRIPTIONS Function 0 Initialize Board Inputs Ms dr d 2
9. Digital I O 8 digital outputs 8 digital inputs Counter Timers 1 32 bit counter timer for A D pacer clock 1 16 bit general purpose counter timer 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 3 2 I O HEADER PINOUT AND PIN DESCRIPTION Diamond MM 6 provides a 50 pin header labeled J3 for all user I O Vin 15 7 Vin 7 7 Vin 14 6 6 6 Vin 13 5 Vin 5 5 Vin 12 4 Vin 4 4 Vin 11 3 Vin 3 3 Vin 10 2 Vin 2 2 Vin 9 1 Vin 1 1 Vin 8 0 Vin 0 0 Agnd Vref Out Agnd Vout 0 Agnd Vout 1 Agnd 15V 15V Vout 2 Agnd Vout 3 In 0 Dgnd Out 0 Out 2 Dout 7 Dout 6 Dout 5 Dout 4 Dout 3 Dout 2 Dout 1 Dout 0 Din 7 Din 6 Din 5 Din 4 Din 3 Din 2 Gate 0 Din 1 Din 0 Gate 1 2 45V Dgnd Signal Name 0 Definition 1 Vin 7 74 Vin 0 0 Analog input channels 7 0 in single ended mode High side of input channels 7 0 in differential mode Vin 15 7 Vin 8 0 Analog input channels 15 8 in both single ended mode Low side of input channels 7 0 in differential mode Vout 0 3 12 bit analog outputs Vref Out 5V precision reference voltage output user adjustable Dout7 DoutO Digital output port TTL CMOS compatible Din7 DinO Digital input port TTL CMOS compatible Din2 Gate 0 Digital input line 2 doubles as the gate control for counter 0 Counter 0 counts when this line is high and holds when it is low DinO Gate 1 2 Digital input
10. Systems Corp Diamond MM 16 User Manual V1 1 Page 16 7 5 AID Conversion Formulas The 16 bit value returned by the A D converter is always a twos complement number ranging from 32768 to 32767 regardless of the input range This is because the input range of the A D is fixed at 10V The input signal is actually magnified and shifted to match this range before it reaches the A D For example for an input range of 0 10V the signal is first shifted down by 5V to 5V and then amplified by 2 to become 10V Therefore two different formulas are needed to convert the A D value back to a voltage one for bipolar ranges and one for unipolar ranges Tables showing the correlation between A D code and input voltage are shown on the following page For bipolar input ranges FS full scale voltage e g 5V for 5V range If using a 16 bit signed integer in C Input voltage A D code 32768 x FS Example 5V range selected A D code 17762 Hex 4560 Input voltage 17762 32768 x 5V 2 7103V Example 5V range selected A D code 15008 Hex C560 Input voltage 15008 32768 x 5V 2 2900V If using a 32 bit signed integer in C or unsigned or floating value in C or Basic Input voltage A D code 32768 x FS If input voltage gt FS then input voltage input voltage 2 x FS Example 5V range selected A D code 17762 Hex 4560 Input voltage 17762 32768 x 5V 2 7103V Example 5V range selected A D co
11. The default is 1MHz The selected frequency feeds the inputs of 82C54 counters 1 and 2 3 5 J7 DMA Level Level 1 Both jumpers installed HORIZONTALLY in RIGHT position Level 3 Both jumpers installed HORIZONTALLY in LEFT position These jumpers are horizontal with respect to the board parallel to the PC 104 connector The default setting is Level 3 NOTE The circuit board markings are incorrect on V2 of this board The left position is marked 1 but is actually level 3 and the right position is marked 3 but is actually level 1 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 6 4 DIAMOND MM 16 BOARD DRAWING O SE O Oj DIFF BOTTOM J4 Q 16 BIT R D CONUERTER UuuUUUUUUUUUTU 12 BIT D R CONUERTER a Ss DMA LEVEL 28 e 3 1 5 Sg o lt BOARD MARKING Se 18 INCORRECT du Ji PC 184 HERDER A J2 PC 184 16 BIT HERDER J8 7 DMM 18 U2 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 7 5 Diamond MM 16 occupies 16 bytes in I O space These registers are described in detail in the next chapter Write Function 0 Start A D conversion D A LSB all channels 2 A D channel register 3 Digital output port 4 D A 0 MSB 5 D A 1 MSB 6 D A 2 MSB 7 D A 3 MSB 8 Clear interrupt flip flop 9 Control register 10 Counter timer enable sele
12. counters are combined together and used as the A D pacer clock Bit 0 of the counter timer control register at base 10 determines whether these counters run freely or whether Input line 0 is the gate see Chapter 6 page 13 This line also has 10 pull up resistor 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 24 12 CALIBRATION PROCEDURE All boards are calibrated at the factory prior to shipment for 10 input range with a gain of 1 and 5V output range Minor offsets and gain errors will occur when using different ranges However these errors may not be significant enough to require recalibration since most adjustments can be performed in software Recalibration is needed primarily if you want to change the D A range or if you want to achieve higher precision for a different A D range To calibrate the board you will need a voltmeter with a precision of at least 5 1 2 digits and a precision voltage source In place of the voltage source you can use the analog outputs on Diamond MM 16 after they have been calibrated but you may have to make adjustments to the target A D readings since the D A only has 12 bits of resolution Note that there are three test points on the board near the top edge These are marked with squares on the silkscreen and are labeled 1 2 3 These test points are used in the calibration procedure Refer to the board diagram on page 7 for the location of the potentiometers mentioned here
13. driver As long as this condition is met Function 46 will work correctly however if direct I O commands to the output registers are mixed with function calls to those registers Function 46 will have unpredictable results on the unselected bits 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 34 Function 47 Interrupt Driven Digital Input Function 48 Interrupt Driven Digital Output Inputs d 1 Number of transfers 1 32767 d 2 Size bit number for I O operation O 7 selects bit I O on DIO DI7 or DOO 007 8 selects byte I O using entire DI or DO port d 3 Operation type single pass 0 or recycle 1 44 Trigger source see page 19 O external signal connected to DIO pin 48 on the I O header 1 internal signal from the output of the counter timer d 5 Segment of memory buffer address or array see text d 6 Offset of memory buffer address or array see text These functions install an interrupt routine to input or output digital data in background mode Each falling edge on the selected trigger source will generate an interrupt request resulting in one transfer of the specified type to from the memory buffer or array Interrupt operation takes over the A D converter so A D conversions cannot be performed when digital I O interrupts are in process In C the buffer can be an integer array using the DSC functions get segment array and get offset array for d b and d 6 see below Miscellaneous Functio
14. following code Input INP ADDR Output OUT ADDR A In both examples a is the data and addr is the address of the port base address plus offset The control register must be programmed to set the direction of the ports being used Upon power up or system reset all ports are set to input and all output registers are set to 0 The output registers can be written to regardless of the direction of the ports If you are using some ports as outputs you may want to write initial values into the output registers before you set those ports to output mode this way when you set the direction to output the signal lines go from high impedance tri state directly to the correct initial value If you set a port to output without first loading its output register whatever is in the register will appear on the output pins This could cause problems depending on your external circuit 14 USING THE DRIVER SOFTWARE Driver software is included to enable interfacing Diamond MM 16 to user programs Four versions are available for the Small Compact Medium and Large models of Microsoft C 5 0 and later and QuickC version 2 0 and later The respective file names are DMM16CS OBJ DMM16CC OBJ DMM16CM OBJ and DMM16CL OBJ The function is declared in file DMM16 H Basic drivers are also included for GW BASIC the file is DMM16 BIN and for QuickBASIC the file is DMM16 OBJ The driver contains a function call to simplify programming Diamond MM 16
15. of the buffer pointer x These functions are provided in the files CNFUNS OBJ and CFFUNS OBJ Use the former file for the Small and Compact models of C and use the latter for the Medium and Large models The functions must be declared inside the C program they will not link properly if defined in a H file Use the following extern int far get buffer extern unsigned get segment extern unsigned get offset 19 TECHNICAL SUPPORT For technical support please call Diamond Systems at 415 813 1100 during the hours 9am 5pm Pacific Time or send email Diamond Systems Corporation 450 San Antonio Rd Palo Alto CA 94306 Tel 415 813 1100 Fax 415 813 1130 techinfo diamondsys com 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 40 20 SPECIFICATIONS Analog Inputs No of inputs A D resolution Input ranges Input bias current Maximum input voltage Overvoltage protection Nonlinearity Conversion rate Conversion trigger Analog Outputs No of outputs D A resolution Output ranges Output current Settling time Relative accuracy Nonlinearity Digital I O No of inputs Input voltage Input current No of outputs Output voltage Output current Counter Timers A D Pacer clock Clock source General purpose Interrupt DMA trigger General Power supply Current consumption header 215 output current Operating temperature Operating humidity PC 104 bus 1998 Diam
16. performing an A D conversion on a selected input channel using direct programming not with the driver software There are six steps involved in performing an A D conversion 1 Select the input channel 2 Select the input range Range Polarity and Gain codes 3 Start an A D conversion on the current channel 4 Wait for the conversion to finish 5 Read the data 6 Convert the numerical data to a meaningful value 8 1 Select the input channel To select the input channel to read write a low channel high channel pair to the channel register at base 2 See Chapter 7 The low 4 bits select the low channel and the high 4 bits select the high channel When you write to this register the current channel is set to the low channel Note When you perform an A D conversion the current channel register on the board is automatically incremented to the next channel in the selected range Therefore to perform A D conversions on a group of consecutively numbered channels you do not need to write the input channel prior to each conversion For example to read from channels 0 2 write Hex 20 to base 2 The first conversion is on channel 0 the second will be on channel 1 and the third will be on channel 2 Then the channel counter wraps around to the beginning again so the fourth conversion will be on channel 0 again and so on This happens automatically without any further channel setting required 8 2 Select the input range S
17. 3 pin 18 and adjust R8 until the meter reads 5 000V If you are setting the analog output full scale range to a voltage other than 5V then adjust R8 to obtain that voltage now 12 9 D A Bipolar Mode Negative Full Scale Reference Write 0 to all four D A channels to set them at their negative full scale value Set the DACs for bipolar mode write 0 to base 11 Adjust R9 until the four outputs are as close as possible to minus the full scale reference adjusted in step 12 8 For example if you are calibrating for a 5V full scale D A range then adjust R9 until the four outputs are as close as possible to 5 000V Note that there are small offsets in each output so each output will deviate somewhat not more than 2LSB from the exact value 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 26 13 PROGRAMMING Two methods of programming are possible either direct access using port read and write statements or using the driver software Diamond MM 16 is a relatively simple board to program so you may prefer to avoid the driver and just use port commands However if you are planning to use interrupts you will most likely find it far simpler to use the driver s built in interrupt support than to write your own interrupt routine and handle the interrupt vectors To program Diamond MM 16 directly in C use the following code Input inp addr Output outp addr a To program Diamond MM 16 directly in Basic use the
18. DIAMOND MM 16 PC 104 Format 16 Bit Analog Module User Manual V1 1 Copyright 1998 Diamond Systems Corporation 450 San Antonio Rd Palo Alto CA 94306 Tel 650 813 1100 Fax 650 813 1130 techinfo diamondsys com TABLE OF CONTENTS 10 11 12 13 14 15 16 18 19 20 DESCRIPTION 3 coco T O HEADER PINOUT AND PIN DESCRIPTION 4 eccccccccccce BOARD CONFIGURATION eeccccccccccccccccccco eoccccccccccccccccccccce DIAMOND MM 16 BOARD DRAWING eecccccccccccccccccecccecce TIO ANALOG INPUT RANGES AND RESOLUTION 15 PERFORMING AN A D CONVERSION e eeeeeee eese e eee een eene en se onsssnsssnsesnsesnsesnsesnseenseenseesees 10 ANALOG OUTPUT RANGES AND RESOLUTION eeeeeeee 21 GENERATING AN ANALOG OUTPUT eere eee enne nennen 22 DIGITAL I O OPERATION eeeeeee eene en sensn senses senses 24 CALIBRATION PROCEDURE eere tenete seen seen seen seen seen ss enees 29 USING THE DRIVER SOFTWARE eeeeeee eese senses ense
19. Full scale output voltage 4096 Example Full scale output voltage 5V 1 LSB 5 4096 1 22mV 9 3 Full ScaleRange Selection The D A converter chip on Diamond MM 16 requires two references one for the low end and one for the high end of the range The high end can be set to any value between 5V and 10V and the low end can be either OV for unipolar output ranges or minus the high end voltage Potentiometer R8 is used to select the high end reference voltage It is preset to 5V To select a different value first move the jumper in J5 above the D A converter IC and near the I O header so that it is over the middle and right pins Then connect a voltmeter to pin 18 on the I O header and adjust R8 until the desired full scale voltage is achieved The low end voltage is selected in software with bit 4 in the analog configuration register at base 11 When this bit is 0 the D A is set for bipolar mode low reference high reference and when this bit is 1 the D A is set for unipolar mode low reference OV On power up this entire register is cleared so the power up mode is always bipolar mode In addition on power up the D A automatically resets to mid scale which is OV in bipolar mode so on power up all D A channels are set to OV 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 21 10 GENERATING AN ANALOG OUTPUT This chapter describes the steps involved in generating an analog output also called per
20. an be read back as bit 7 in the status register at base 8 When the A D converter is busy performing an A D conversion this bit is 1 and when the A D converter is idle conversion is done and data is available this bit is 0 Here is a pseudocode explanation Status read base 8 AND 128 or Status read base 8 AND 80 Hex If Status 0 then conversion is complete else A D converter is busy Keep repeating this procedure until Status 0 8 5 Read the data Once the conversion is complete you can read the data back from the A D converter The data is 16 bits wide and is read back in two 8 bit bytes Refer to the register definitions on p 8 for the format of the A D data The following pseudocode illustrates how to construct the 16 bit A D value from these two bytes LSB read base Get low 8 bits MSB read base 1 Get high 8 bits Data MSB 256 LSB Combine the 2 bytes into a 16 bit value The final data ranges from 0 to 65535 0 to 2 1 as an unsigned integer This value must be interpreted as a signed integer ranging from 32768 to 32767 8 6 Convert the numerical data to a meaningful value Once you have the A D value you need to convert it to a meaningful value The first step is to convert it back to the actual measured voltage Afterwards you may need to convert the voltage to some other engineering units for example the voltage may come from a temperature sensor and then you would need to convert the voltage to
21. ar Interrupt Flip Flop Writing to this register clears the on board interrupt flip flop The value written does not matter The interrupt flip flop is set whenever an interrupt is generated on Diamond MM 16 i e during A D conversions and it must be cleared by software before another interrupt can be generated Diamond MM 16 s software driver includes an interrupt handler that performs this task automatically Base 8 Bit No Name STS U B S D INT ADCHS 0 A D chip status 1 A D conversion in progress 0 A D idle Unipolar Bipolar A D input mode setting 1 unipolar A D can measure only positive input voltages 0 bipolar default A D can measure both negative and positive input voltages Single ended Differential A D input mode setting 1 Single ended default 0 Differential Interrupt request status 1 Interrupt is pending A D has generated a new value 0 No interrupt is pending Note A D conversions continue to occur on schedule regardless of whether this bit is cleared If a new conversion occurs before this bit is cleared an overrun condition will occur and the unread A D value will be lost There is no way to tell if an overrun condition has occurred Therefore the programmer must ensure that the interrupt rate is not faster than the capability of the system and program to respond Current A D channel this is the channel currently selected on board and is the channel that will be used for th
22. by counter 1 and counter 1 is driven by either a 1MHz or 10MHz signal derived from the on board clock oscillator J9 is used to select the frequency source Thus both counters 1 and 2 must be programmed to generate a time base for A D conversions The sample rate becomes Rate 1MHz or 10MHz counter 1 divider value x counter 2 divider value If an external trigger is used connect it to pin 48 DIO on the I O header This pin requires an active low TTL signal to generate conversions It is wired to a 10K ohm pull up resistor so just a pull down to ground is required if the signal is being driven externally The trigger is edge sensitive one A D conversion or scan is performed for each low going edge Both Functions 3 and 4 can be used to acquire data at rates of up to about 20 000 30 000 samples per second The actual upper limit is platform dependent and can only be determined through experiment For Function 5 the upper limit is approximately 100 000 samples per second since the software overhead of the interrupt routine is eliminated Again the actual limit is plattorm dependent External A D clock gate When d 7 1 and external A D clock is enabled d 5 0 signal INO pin 29 on the I O header acts as a gate on the external A D clock signal connected to DIO pin 48 on the I O header When INO is low the external A D clock is inhibited and when INO is high falling edges on the external signal generate A D conversions
23. ct 11 Analog range configuration 12 Counter timer 0 data register 13 Counter timer 1 data register 14 Counter timer 2 data register 15 Counter timer control register 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Read Function A D LSB bits 7 0 A D MSB bits 15 8 A D channel register Digital input port Update all D A channels Update all D A channels Update all D A channels Update all D A channels Status register Control register readback Not used Analog range readback Counter timer 0 data register Counter timer 1 data register Counter timer 2 data register Counter timer control register Page 8 6 REGISTER DEFINITIONS Base 0 Bit No Name Definitions AD7 0 A D data bits 7 0 ADO is the LSB Base 1 Bit No Name Definitions AD15 8 A D data bits 15 8 AD15 is the MSB The A D value is twos complement 16 bit signed integer ranging from 32768 to 32767 The value is constructed from the two bytes at Base 0 and Base 1 by using the formula A D value Base 1 256 Base 0 A reading of 32768 represents a negative full scale input or below and a reading of 32767 represents an input of positive full scale minus 1 LSB or above See Chapter 7 for formulas to convert the 16 bit A D reading into the corresponding voltage Base 0 Write Start A D Conversion Writing to Base 0 starts an A D conversion unless a conversion is already in progress The
24. d Systems Corp Diamond MM 16 User Manual V1 1 Page 25 12 4 A D Unipolar Range Offset Adjust Connect channel 0 to analog ground wire J3 pin 16 to J3 pin 17 Select channel 0 as the current input channel write 0 to base 2 Select a gain of 1 and 0 10V range write 12 to base 11 Connect the voltmeter to test point 3 and adjust R4 until the meter reads 10 000V 12 5 A D Unipolar Range Gain Adjust Connect channel 0 to the output reference wire J3 pin 16 to J3 pin 18 Select channel 0 as the current input channel write 0 to base 2 Select a gain of 1 and 0 10V range write 12 to base 11 Connect the voltmeter to test point 3 and adjust R3 until the meter reads 2 times the reference voltage measured above minus 10V or approximately OV 12 6 A D Offset Adjust Connect channel 0 to analog ground wire J3 pin 17 to J3 pin 16 Select channel 0 as the current input channel write 0 to base 2 Select a gain of 1 and 10V range write 8 to base 11 Perform A D conversions and adjust R1 until the A D readings are centered around 0 12 7 A D Gain Adjust Connect channel 0 to 9 999V Select channel 0 as the current input channel write 0 to base 2 Select a gain of 1 and 10V range write 8 to base 11 Perform multiple A D conversions and adjust R2 until the A D readings average 32765 12 8 D A Positive Full Scale Reference Jumper on J5 needs to be installed over the middle and right pins Connect the voltmeter to J
25. de 50528 Hex C560 Input voltage 50528 32768 x 5V 7 7100V Since 7 7100V gt 5V we must subtract Input voltage 7 7100V 2 x 5V 2 2900V For unipolar input ranges FS full scale voltage e g 10 for O 10V range Input voltage A D code 32768 65536 x FS Example 0 10V range selected A D code 17762 Hex 4560 Input voltage 17762 32768 65536 x 10V 7 7103V Note that this is simply the result for the 5V range shifted up by 5V 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 17 7 6 Correlation between A D Code and Input Voltage The two tables below illustrate the correlation between the A D code and the corresponding input voltage Use these tables as guides to help think about how to convert between the voltage domain and the A D code domain Bipolar Input Ranges A D Code 32768 32767 1 0 1 32767 Input voltage formula Ves Vrs 1 LSB 1 LSB OV 1 LSB Ves 1 LSB Unipolar Input Ranges A D Code 32768 32767 Input voltage formula OV 1 LSB Ves 65536 Ves 2 1LSB Ves 2 Vrs 2 1 LSB Ves 1 LSB 1998 Diamond Systems Corp Input voltage 5V range 5 0000 V 4 9998 V 0 153mV 0 0000V 0 153mV 4 9998V Input voltage 0 10V range 0 0000V 0 153mV 4 99985V 5 0000V 5 00015V 9 9998 V Diamond MM 16 User Manual V1 1 Page 18 8 PERFORMING A D CONVERSION This chapter describes the steps involved in
26. e for I O devices Base Address Hex 100 140 180 1C0 200 240 280 2C0 300 340 380 Pin Header J8 Configuration Decimal 9 256 Installed 320 Installed 384 Installed 448 Installed 512 Open 576 Open 640 Open 704 Open 768 Default Open 832 Open 896 Open 960 Open 8 Open Open Open Open Installed Installed Installed Installed Open Open Open Open 3 2 J4 Single Ended Differential A D Mode Single ended mode Both jumpers VERTICAL in upper position over top amp middle pins Both jumpers VERTICAL in lower position over middle amp bottom pins Differential mode In Single ended mode Diamond MM 16 has 16 input channels numbered 0 15 7 Installed Installed Open Open Installed Installed Open Open Installed Installed Open Open 6 Installed Open Installed Open Installed Open Installed Open Installed Open Installed Open In Differential mode Diamond MM 16 has 8 input channels numbered 0 7 The high sides of the inputs are on pins 2 through 16 even and the low sides of the inputs are on pins 1 through 15 odd The default setting is Single ended mode 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 5 3 3 95 Output Reference Voltage 5 000V Jumper in left position 5 000V Jumper in right position The default setting is 5 000V 3 4 J6 Counter Timer Input Clock Frequency 10MHz Jumper in lower position 1MHz Jumper in upper position
27. e next A D conversion unless a new value is written to the channel register 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 12 Base 9 INTE INT2 0 DMAEN TRIGE INTTRIG Base 10 Bit No Name C2 C1 CO Read Write Control Register Paice MUNERE NEUE Interrupt enable 1 Enable interrupts 0 Disable interrupts Interrupt level select 011 level 3 100 level 4 etc INT2 is the MSB Only levels 2 7 are valid levels 0 and 1 are not connected on the board Don t Care the value of this bit is ignored DMA enable DMA operation is explained later in this manual 1 Enable DMA operation 0 Disable DMA operation Enable hardware A D trigger 1 Enable hardware trigger source is selected with INTTRIG bit 0 Disable hardware trigger A D trigger select 1 Internal trigger Rising edges on the output of counter timer 2 82C54 generate conversions 0 External trigger Falling edges on DIO Trigger 48 on I O connector J3 generate A D conversions External gate enable 1 INO pin 29 on the I O header acts as a gate for A D sample control when external A D clock is enabled INTTRIG 0 above When INO is high falling edges on DIO pin 48 on the O header will initiate A D conversions When INO is low the DIO signal is inhibited INO is connected to a 10KQ pullup resistor 0 INO does not act as a gate for external A D clocking
28. elect the code from Table 7 1 corresponding to the desired input range and write it to the analog I O control register at Base 11 You only need to write to this register if you want to select a different input range from the one used for the previous conversion Note You can read the current value of this register by reading from Base 11 There is one more bit in this register that corresponds to the D A mode so you should be careful not to erase this bit accidentally if it has been previously set 8 3 Start an A D conversion on the current channel After selecting the channel register and or the input range about 10 microseconds is required as a settling time for the analog front end circuitry You can implement this delay as a short software loop After waiting for the analog circuitry to settle you can perform an A D conversion on the selected channel To do this simply write to base 0 to start the conversion The value you write does not matter and is ignored 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 19 8 4 Wait for the conversion to finish The A D converter takes up to 10 microseconds to complete a conversion Most processors and software can operate fast enough so that if you try to read the A D converter immediately after writing to base 0 you will beat the A D converter and get invalid data Therefore the A D converter provides a status signal to indicate whether it is busy or idle This bit c
29. f low 8 bits keep 4 high bits Example Output code 1776 LSB 1776 AND 255 240 FO Hex MSB int 1776 256 int 6 9375 6 In other words 1776 6 256 240 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 22 10 3 Write the value to the selected output channel The LSB for all channels is written to base 1 while the MSB is written to address base 4 through base 7 for channel 0 through 3 respectively Here are the relevant portions of the map Base Write Function Read Function 4 D A LSB all channels A D MSB bits 15 8 4 D A 0 MSB Update all D A channels 5 D A 1 MSB Update all D A channels 6 D A 2 MSB Update all D A channels 7 D A 3 MSB Update all D A channels The register at base 1 is actually a holding register and the value in it does not reach the DAC until the MSB is written When the MSB is written all 12 bits are loaded simultaneously into the selected DAC channel Therefore you must write the L SB first At this point the DAC will still remain at its current output voltage To update the DAC to its new output voltage you must perform a read operation from any address in the range base 4 through base 7 The value read is not meaningful This read operation actually updates all 4 channels simultaneously allowing synchronization of the update time for multiple channels Any channel that does not have a new value loaded into it will remain stable at its current value and a
30. forming a D A conversion on a selected output channel using direct programming not with the driver software There are two steps involved in performing a D A conversion 1 Compute the D A output value for the desired output voltage 2 Compute the LSB and MSB values 3 Write the value to the selected output channel 10 1 Compute the D A code for the desired output voltage A different formula is required for bipolar and unipolar output ranges Use the following formula to compute the D A code in unipolar mode Output value Output voltage Full scale voltage 4096 Example Desired output voltage 2 168 full scale voltage 5V unipolar mode 0 5 Output code 2 168 5V 4096 1776 Use the following formula to compute the D A code in bipolar mode Output value Output voltage Full scale voltage 2048 2048 Example Desired output voltage 2 168V full scale voltage 5V bipolar mode 5V Output code 2 168 5V 2048 2048 1160 Note The DAC cannot generate the actual full scale reference voltage to do so would require an output code of 4096 which is not possible with a 12 bit number The maximum output value is 4095 Therefore the maximum possible output voltage is 1 LSB less than the full scale reference voltage 10 2 Compute the LSB and MSB values Use the following formulas to compute the LSB and MSB values LSB D A Code AND 255 keep only the low 8 bits MSB int D A code 256 strip of
31. going pulse one clock wide every n clocks where n is the data in d 3 The input to counter 2 is jumper selected via J9 to either 1MHz or 10MHz and the output of counter to 2 is connected to the input of counter 1 Thus the counter 2 counter 1 combination provides a 32 bit divider for the 10MHz clock for interrupt and DMA operation timing Counter 1 s output can be selected as the trigger source for any interrupt or DMA operation or an external signal can be used If the counter timer is used as the trigger source remember that both counters 1 and 2 must be programmed Normally Mode 2 is selected for these counters The final operation rate is determined by the formula Rate 1MHz or 10 2 counter 1 divider value x counter 2 divider value A complete 82C54 datasheet is provided at the back of this manual to assist in using the counter timer circuit 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 36 Function 62 Counter Timer Readback Command Inputs En d 1 Nonzero to read back Counter O data status d 2 Nonzero to read back Counter 1 data status d 3 Nonzero to read back Counter 2 data status Outputs d 4 Current count value of counter 0 if selected else 0 d 5 Current count value of counter 1 if selected else 0 d 6 Current count value of counter 2 if selected else 0 47 Current status of counter 0 if selected else 0 d 8 Current status of counter 1 if selected else 0 d 9 Current status of counte
32. ings in the Analog Configuration Register at base 11 In front of the A D converter is a programmable gain amplifier that multiplies the input signal before it reaches the A D This gain circuit has the effect of scaling the input voltage range to match the A D converter for better resolution In general you should select the highest gain you can that will allow the A D converter to read the full range of voltages over which your input signals will vary However if you pick too high a gain then the A D converter will clip at either the high end or low end and you will not be able to read the full range of voltages on your input signals 7 3 Single Ended and Differential Inputs Diamond MM 16 can handle both single ended and differential inputs A single ended input is a single wire input that is referenced to analog ground on the board This means that the input voltage will be measured with respect to the board s analog ground A differential input is a two wire input and the board will measure the difference between the voltages of the two inputs Polarity is important for a differential input Diamond MM 16 will subtract the voltage on the low input from the voltage of the high input Differential inputs are frequently used when the grounds of the input device and the measurement device Diamond MM 16 are at different voltages or when a low level signal is being measured that has its own ground wire A 16 bit A D converter is extremel
33. ion 7 5 on page 17 for conversion formulas to compute the input voltage from the A D code Function 2 Single A D scan across channel range Inputs Es d 1 Low channel in scan range O 15 d 2 High channel in scan range 0 15 d 3 Gain code see table above d 4 Full scale range code see table above Outputs d 1 A D code for first channel in scan range A D code for last channel in scan range n lt 16 This function performs a single A D conversion on the selected range of input channels Up to 16 channels can be selected in the scan range and the high channel must be higher than the low channel 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 30 Function 3 Interrupt driven single A D conversions Function 4 Interrupt driven A D scans Function 5 DMA driven single A D conversions Inputs Sae d 1 Number of conversions 1 32767 d 2 Segment of memory buffer address or array see text d 3 Offset of memory buffer address or array see text d 4 Operation type single pass 0 or recycle 1 d 5 A D clock source 0 External A D clock falling edges on an external signal connected to DIO pin 48 on the I O header generate A D conversions 1 Internal A D clock rising edges on the output of counter timer no 2 on the board generate A D conversions d 6 Low channel in scan range 0 15 47 High channel scan range 0 15 d 8 External A D clock gate enable used only when d 5
34. l interrupt Since an integer array can be used directly as a buffer for interrupt operation this function is not normally necessary for C programs 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 38 Function 81 Interrupt DMA Operation Statistics Outputs d 1 Status O inactive 1 active d 2 No of transfers completed or position in buffer d 3 Operation type 0 no operation in progress 1 interrupt operation in progress or halted 2 operation in progress or halted d 4 Direction 0 input 1 output This function returns information on any interrupt operation in progress Note that only one interrupt operation may be in progress at any time for a given board Valid return combinations of d 1 and d 3 are d 1 20 d 3 20 operation is in progress or any prior operation has completed successfully d 1 0 d 3 1 single pass interrupt or DMA operation was terminated prematurely with Function 82 causing less than the requested number of interrupts to be completed d 1 1 d 8 2 1 An interrupt DMA operation is in progress The value in d 2 is the one of primary interest In single pass mode it indicates the number of data values which have been input or output and in recycle mode it indicates the current buffer or array position at which the next interrupt or DMA operation will store or retrieve data This can be used to synchronize a program to the interrupt routine o
35. line 0 can be used as a gate signal for counters 1 and 2 or as an external A D trigger as determined by the control register at base 11 InO Counter 0 input negative polarity negative edge trigger also used as an external gate if external A D triggering is used Out2 Counter 0 and Counter 2 output signals 15V Analog power supply maximum current draw 10mA per line 5V Connected to PC 104 bus power supply Agnd Analog ground connected to digital ground at a single point at device PS1 Dgnd Digital ground connected to PC 104 bus ground 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 4 3 BOARD CONFIGURATION Refer to the Drawing of Diamond MM 16 in chapter 4 for locations of the configuration items mentioned here 3 1 J8 Base Address Each board in the system must have a different base address Diamond MM 16 s base address is set with pin header 48 located at the lower left corner of the board Each of the four pairs of pins on J8 corresponds to a different address bit as indicated underneath the header An open location is equal to a 1 and an installed location is equal to a 0 The dipswitch is used to select address bits 9 6 resulting in an address decode on 64 byte boundaries However the board only occupies the lowermost 16 bytes of the selected address block The table below lists the possible base address settings The default setting is 300 Hex Note that addresses below 100 Hex are not availabl
36. nd Systems Corp Diamond MM 16 User Manual V1 1 Page 33 Function 41 Digital Byte Input Output d 1 Data from input port range 0 255 Function 41 returns the 8 bit data appearing on the I O header pins 41 48 Pin 41 contains the MSB DI7 and pin 48 contains the LSB DIO Function 42 Digital Byte Output Input ooo d 1 Output data range 0 255 Function 42 writes the specified 8 bit data to the digital output port on I O header pins 33 40 Pin 33 is the MSB 007 and pin 40 is the LSB 000 Only the lower 8 bits of the 16 bit integer variable d 1 are used for output the remaining bits are ignored Function 45 Bit Input Inputs ES SS d 2 Bit number 0 7 corresponding to digital input lines DIO DI7 Output 1 value O 1 Function 45 returns the value of the selected bit d 1 Function 46 Bit Set Reset Inputs d 1 Bit value O or 1 d 2 Bit number 0 7 corresponding to digital output lines DOO DO7 This function sets the selected output bit to the same value as the least significant bit of the value d 1 i e if d 1 is even the bit is set to 0 and if d 1 is odd the bit is set to 1 The contents of the remaining bits on the output port are not disturbed The driver software maintains copies of the contents of all the output registers on Diamond MM 16 but these copies are valid only as long as all access to the board is through the
37. nput signal range of 0 2 5V On power up or system reset the board is configured for D A bipolar mode A D bipolar mode input range 5V gain of 1 Base 11 Read Test Readback Register This address provides a means of reading back the values written to the registers at Base 10 and Base 11 Base 12 Base 15 Read Write 82C54 Counter Timer Registers These registers map directly to the 82C54 The definitions of these registers can be found in the 82C54 datasheet appended to the back of this manual 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 14 7 ANALOG INPUT RANGES AND RESOLUTION 7 1 Resolution Diamond MM 16 uses a 16 bit A D converter This means that the analog input voltage can be measured to the precision of a 16 bit binary number The maximum value of a 16 bit binary number is 2 1 or 65535 so the full range of numerical values that you can get from a Diamond MM 16 analog input channel is 0 65535 The smallest change in input voltage that can be detected is 1 2 or 1 65536 of the full scale input range This smallest change results in an increase or decrease of 1 in the A D code and so this change is referred to as 1 LSB or 1 least significant bit 7 2 Unipolar and Bipolar Inputs Diamond MM 16 can measure both unipolar positive only and bipolar positive and negative analog voltages The full scale input voltage range depends on the Gain Range and Polarity bit sett
38. ns In Basic the values for segment and offset must be specified as an address somewhere in free memory A typical example is segment amp H4000 and offset 0 For an input operation typically the data is transferred to an integer array using Function 80 after Function 47 has been called and the interrupt operation is complete or during the operation if recycle mode is selected For an output operation typically the data is placed in memory from an array by using Function 80 prior to using Function 48 The operation type indicator determines the use of this buffer If d 4 0 then d i conversions are performed and then interrupts stop If d 4 1 then after d 1 transfers the internal buffer pointer is reset to the start and future interrupts recommence from that position Thus in input mode the most recent d 1 input values are always in memory or the array and in output mode a periodic digital waveform with d 1 values will be output The current position in the buffer can be acquired by using Function 81 see below 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 35 Function 61 Program Counter Timer Inputs d 1 Counter no 0 2 d 2 Counter mode 0 5 d 3 Counter data 16 bit integer This function programs the counter timer for rate generator or counting functions See the 8254 datasheet for counter mode definitions The most common mode is 2 which implements a rate generator with a negative
39. ny channel that has new data loaded into it will update to its new value Example Write a value of 1776 to channel 1 From above LSB 240 MSB 6 1 Write 240 to base 1 2 Then write 6 to base 5 3 Then read from base 5 to update the DAC 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 23 11 DIGITAL I O OPERATION Diamond MM 16 contains an 8 bit digital output port and an 8 bit digital input port Both ports are located at base 3 To access the output lines simply write an 8 bit value to base 3 Similarly to read the input lines read from base 3 The output lines are located at pins 33 through 40 on the I O header J3 see Chapter 2 4 They are CMOS TTL compatible and can drive up to 6 max per line They do not have a readback feature so your program must keep track of the latest output value The inputs are located at pins 41 through 48 on the I O header J3 They are also CMOS TTL compatible There is no latch signal provided However the values are latched when being read to prevent transitions during the CPU read operation Input line 2 doubles as the gate control for counter 0 When it is high counter O can count and when it is low counter 0 holds its present value This line has 10KQ pull up resistor on board to force it to a default high state to enable counter 0 when there is no input signal connected Input line 0 doubles as a programmable gate control for counters 1 and 2 These
40. ond Systems Corp 8 differential or 16 single ended user selectable 16 bits 1 65536 of full scale Bipolar 10V 5V 2 5V 1 25V 0 625V Unipolar 0 10V 0 5V 0 2 5V 0 1 25V 50nA max 10V for linear operation 235 on any analog input without damage 1LSB no missing codes 100 000 samples per second max with DMA single channel software trigger internal pacer clock or external TTL signal 4 12 bits 1 4096 of full scale Unipolar 0 5V adjustable to 0 10V Bipolar 5V adjustable to 10V 5 max per channel 6uS max to 1 2 LSB 1 LSB 1 LSB monotonic 8 HCT TTL compatible Logic 0 0 0V min 0 8V max Logic 1 2 0V min 5 0V max 1 max 8 HCT TTL compatible reset to 0 power up Logic 0 0 0V min 0 33V max Logic 1 3 8V min 5 0V max 4mA per line 32 bit down counter 2 82C54 counters cascaded 10MHz on board clock source or external signal 16 bit down counter 1 82C54 counter End of A D conversion 5VDC 10 200mA typical 10 max with DACs unloaded not short circuit protected 25 to 85 C 5 to 95 noncondensing 8 bits Diamond MM 16 User Manual V1 1 Page 41
41. r 2 if selected else 0 This function implements the 8254 readback command It will return the current contents of each counter s count register and the current state of each counter s output line Function 63 Direct Counter Access Inputs SS d 1 Counter mode register value d 2 Counter data This function is provided for programming the counter timer for modes not supported directly by Function 62 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 37 Function 80 Data Transfer Between Memory and Program Array Inputs for C ae d 1 No of transfers O 32767 d 2 Source data size must be set to 1 for Diamond MM 16 d 3 Segment portion of source address d 4 Offset portion of source address d 5 Destination data size must be set to 1 for Diamond MM 16 d 6 Segment portion of destination address 47 Offset portion of destination address Inputs for Basic d 1 No of transfers 0 32767 d 2 Source data size must be set to 1 for Diamond MM 16 d 3 Segment portion of source address for an array this is 0 d 4 Offset portion of source address for an array this is varptr array d 5 Segment portion of destination address for an array this is 0 d 6 Offset portion of destination address for an array this is varptr array Function 80 is used to transfer data between arrays and memory typically before during or after using Functions 3 4 or 5 for analog input or Functions 47 and 48 for digita
42. r DMA operation with the program extracting data from the buffer or array as soon as it is inserted or vice versa Function 82 Halt Resume Interrupt or DMA Operation Input E d 1 0 halt operation 1 resume operation An interrupt or DMA operation can be halted and resumed as often as desired unless it terminates automatically in one shot mode A single pass operation will automatically halt after the requested number of interrupts is completed A one shot operation which terminates automatically cannot be restarted with Function 82 but must be reinstated with the original function 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 39 18 MISCELLANEOUS FUNCTIONS Three auxiliary functions are provided to facilitate buffer pointer handling in C These are get buffer x get segment x and get offset x int FAR get buffer x returns a 4 byte pointer to a buffer in memory containing at least x integers of free space 2x bytes within a single segment Generally this function is not necessary for small buffers around 1000 points but for large buffers it is a good way to guarantee that memory will not be corrupted since the DSC driver increments only the offset portion of the buffer pointer and leaves the segment portion alone unsigned get segment x returns the segment portion of the buffer pointer x which can be an array or a pointer from get buffer unsigned get offset x returns the offset portion
43. s sens sons sense ense sns sense ense sn 27 DRIVER FUNCTION 28 DRIVER FUNCTION DESCRIPTIONS e eeeeeee eene eene enses sense ona sense sn seen seen seen seen seen seen seen ses 29 MISCELLANEOUS FUNCTIONS eeeeeeee eee eene eene een senses senses senses SD 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 2 DIAMOND MM 16 PC 104 16 Bit Analog I O Module 1 DESCRIPTION Diamond MM 16 is a PC 104 format multifunction data acquisition board It offers 16 single ended or 8 differential analog inputs with 16 bit resolution and programmable input range 100 000 samples per second maximum sampling rate with DMA operation 4 analog outputs with 12 bit resolution user adjustable analog output range 8 bits of digital input 8 bits of digital output one 32 bit counter timer for A D conversion timing and one 16 bit counter timer for general purpose use 1 1 Features Analog Inputs 16 single ended 8 differential analog input channels with 16 bit resolution Programmable gain range and polarity on inputs 100 000 samples per second maximum sampling rate on A D Software interrupt and DMA A D sampling control Analog Outputs 4 analog output channels with 12 bit resolution max output current 15V 10 output power for user circuitry 5V up to 10V 9 up to 10mA precision reference output for sensors or user circuitry Note total output current limited to 30mA
44. t there is no restriction on the selection of the low and high channels Any combination of two channel numbers is valid For example 0 and means that channels 0 3 will be read in sequence 4 channels and 12 and 2 means that 7 channels will be read in sequence 12 15 then 0 2 If d 6 and d 7 are different then the following applies For function 3 each interrupt results in one new conversion on the current channel and then the board switches to the next channel in the sequence for the next conversion For function 4 each interrupt results in a reading of each channel in the scan range d 6 through d 7 For function 5 each DMA cycle results in one new conversion on the current channel as in Function 3 If d 6 d 7 then each interrupt DMA operation results in a single conversion on the same channel Function 4 with d 6 d 7 is identical to Function in operation 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 31 Trigger source Functions 3 4 and 5 as well as Functions 47 and 48 below can be triggered either from the on board counter timer or from an external digital signal on pin 48 of the I O header signal DIO If the counter timer is used then it must be programmed for the correct sample rate before Functions 3 4 or 5 are called See Function 61 for counter timer programming Note that the output of counter 2 is used to drive the interrupt or DMA operation counter 2 is in turn driven
45. the corresponding temperature according to the temperature sensors characteristics Both of these conversions can be done simultaneously by combining them into a single conversion formula See Section 7 5 on Page 17 for an explanation on converting A D codes to input voltage and the required formulas Although the A D data range always includes both negative and positive values the input voltage may be unipolar requiring an offset to be added in during the conversion calculation 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 20 9 ANALOG OUTPUT RANGES AND RESOLUTION 9 1 Description Diamond MM 16 uses a four channel 12 bit D A converter DAC to provide four analog outputs A 12 bit DAC can generate output voltages with the precision of a 12 bit binary number The maximum value of a 12 bit binary number is 2 1 or 4095 so the full range of numerical values that you can write to the analog outputs on Diamond MM 16 is 0 4095 Note In this manual the terms analog output D A and DAC are all used interchangeably to mean the same thing 9 2 Resolution The resolution is the smallest possible change in output voltage For a 12 bit DAC the resolution is 1 2 or 1 4096 of the full scale output range This smallest change results from an increase or decrease of 1 in the D A code and so this change is referred to as 1 LSB or 1 least significant bit The value of this LSB is calculated as follows 1 LSB
46. up or system reset the digital output port is set to all zeroes Base 3 Digital Input Port Bit No Name These pins correspond directly to the same named pins on I O connector J3 pins 41 48 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 10 Base 4 Write DAC 0 MSB Base 5 Write DAC 1 MSB Base 6 Write DAC 2 MSB Base 7 Write DAC 3 MSB Bit No Name Definitions X Don t Care these bits are ignored DA11 8 D A bits 11 8 for the selected output DA11 is the MSB D A data is an unsigned 12 bit value Base 4 Read Update All D A Channels Base 5 Base 6 Base 7 Bit No Name Definitions X Don t Care these bits have no meaning Reading from any of these addresses causes all 4 D A channels to update simultaneously with the values loaded into their load registers Any channel which has had a new value written to it since the last update command will settle on its new value Any channel which has not had a new value written will maintain its present value without glitching Writing to a D A requires three steps 1 Write the LSB to base 1 2 Write the MSB to base 4 to base 7 depending on the channel you are controlling 3 Read from the same address to which you wrote the MSB actually any address from base 4 to base 7 will work but this technique is a bit simpler 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 11 Base 8 Write Cle
47. y sensitive to noise and ground currents so differential measurements are recommended whenever possible Jumper block J4 is used to select single ended or differential mode To select single ended more insert the two jumpers vertically over the top and middle pins and to select differential mode insert the two jumpers vertically over the bottom and middle pins 1998 Diamond Systems Corp Diamond MM 16 User Manual V1 1 Page 15 7 4 Input Ranges and Resolution Here is a table describing the full scale input range for each possible analog input configuration The parameters Polarity Range and Gain are combined to create the value Code which is the value that you must write to the analog configuration register at Base 11 to get the input range shown A total of 9 different input ranges are possible Note that the range programming codes 4 5 6 and 7 are invalid Table 7 1 Polarit Range Gain Code Full Scale Range A Resolution 1 LSB Bipolar 5V 1 0 5V 153 uV Bipolar 5V 2 1 2 5V 76 uV Bipolar 5V 4 2 1 25V 38 uV Bipolar 5V 8 3 0 625V 19 uV Unipolar 5V 1 4 Invalid setting Unipolar 5V 2 5 Invalid setting Unipolar 5V 4 6 Invalid setting Unipolar 5V 8 7 Invalid setting Bipolar 10V 1 8 10V 305 uV Bipolar 10V 2 9 5V 153 uV Bipolar 10V 4 10 2 5V 76 uV Bipolar 10V 8 11 1 25V 38 uV Unipolar 10V 1 12 0 10V 153 uV Unipolar 10V 2 13 0 5V 76 uV Unipolar 10V 4 14 0 2 5V 38 uV Unipolar 10V 8 15 0 1 25V 19 uV 1998 Diamond
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