4A23 USER`S MANUAL
Contents
1. ds eds 14 SEQUENCE FILE FORMAT aa IS 14 4AA23 RDM pomises lumi sd da las pda 17 REFERENCE INFORMATION SPECIFICATIONS WARRANTY enr ber Eia ea tia kadaka SCHEMATICS 55 diei aal 4A23USERSMANUAL WARNINGS HIGH VOLTAGES The 4A23 analog ground is isolated from system ground and can be at dangerous potentials during normal operation DO NOT touch the 4A23 card or the input section shield when operating STATIC ELECTRICITY CMOS integrated circuits on the 4A23 can be damaged by exposure to electrostatic discharges The following precautions should be taken when handling the 4A23 to prevent possible damage A Leave the 4A23 in its antistatic bag until needed B All work should be performed atan antistatic workstation C Ground equipment into which 4A23 will be installed D Ground personnel with conductive bracelet through 1 meg resistor to ground E Avoid wearing synthetic fabrics particularly Nylon Page 4 4A23USERSMANUAL DESCRIPTION GENERAL The 4A23 is ahighresolution low power delta sigma A D card for the PC 104 bus 8 differential or 16 single ended inputs are provided The inputs have 500V isolation from system ground for noise elimination and to permit floating measurements The 4A23 has 5 programmable input2. 7 PPM C Page 19 4A23USERSMANUAL REFERENCE INFORMATION BUS LOADING Input capacitance 15 pF Input leakage current uA Output drive capability 150 pF Output sink current 8 ENVIRONMENTAL Operating temperature range version 40 85 C version 0 470 C Relative humidity 0 90 Percent Non condensing Page 20 4A23USERSMANUAL REFERENCE INFORMATION WARRANTY Mesa Electronics warrants the products it manufactures to be free effects in material and workmanship under normal use and service for the period of 2 years from date of purchase This warranty shall not apply to products which have been subject to misuse neglect accident or abnormal conditions of operation In the event of failure of a product covered by this warranty Mesa Electronics will repair any product returned to Mesa Electronics within 2 years of original purchase provided the warrantor s examination discloses to its satisfaction that the product was defective The warrantor may at its option replace the product in lieu of repair With regard to any product returned within 2 years of purchase said repairs or replacement will be made without charge If the failure has been caused by misuse neglect accident or abnormal conditions of operation repairs will be billed at a nominal cost If any failure occurs the following steps should be taken 1 Notify Mesa Electronics giving full details of the difficulty On receipt of
3. Failed usually means an unimplemented function Bad parameter means that the channel or range number is not valid 4A23DCFG After 4A23DRVR is installed it need to be configured in order to set up its operating parameters and background data aquisition loop This is done with the program 4A23DCFG 4A23DCFG loads various user specified parameters and a sequence table into the driver The user parameters and sequence table are in an ASCII text file This file is referered to as a sequence file 4A23DCFG is invoked with the sequence file filename and the 4A23DRVR software interrupt number on the command line 4A23DCFG SEQFILE 60 Would configure the driver using software interrupt 60H with the sequence file SEQFILE SEQUENCE FILE FORMAT The sequence file specified on the 4A23DCFG command line is an ASCII text file consisting of lines terminated with a CR LF Each line starts with a token an ascii name and zero one or two parameters A combination ofa token followed by its parameters is called a statement Lines that start with a semicolon are ignored and can be used for comments The tokens are not case sensitive but are printed here in upper case for emphasis There is an example sequence file SEQFILE in the DRIVER directory of the 4A23 distribution floppy The sequence file has three sections a parameter specification section a A D startup section and a data aquisition loop section The maximum length of the combined A D startup and
4. address and software interrupt are specified in hex but the hardware interrupt is specified in decimal as is standard practice with hardware interrupts The base address must match the base address setting of the 4A23 in the system This is the address selected via jumpers W6 and W7 The hardware interrupt must not be used by any other peripheral in the system Usually while at least one of IRQ 5 9 10 11 and 12 are available in AT PC 104 systems The software interrupt uses one of the so called user interrupt vectors from 60H to 6FH The driver attempts to check if the software interrupt is used before installing itself but you should make sure that no other installed software uses the same interrupt vector Once installed all communication to the driver is done via the software interrupt The same calling convention and data record structure is used for all driver functions The driver is accessed by calling its software interrupt with the register pair CX BX CX segment B X offset pointing to the data record Page 10 4A23USERSMANUAL 4 23 SOFTWARE 4A23DRVR RECORD STRUCTURE To avoid a multiplicity of record structures for 4A23DRVR communication a single record is used It is the responsibility of the calling program to allocate the record structure and provide 4A23DRVR with a pointer to it The calling program must set CX BX to point to the record on entry The record size is 13 bytes total The range value is the actual value used t
5. aquistion loop sections is 128 statements Page 14 4A23USERSMANUAL 4A23 SOFTWARE SEQUENCE FILE FORMAT The sequence file has 2 sections a parameter specification section and a acquisition loop section The parameter specification section has only one possible statement SETRATE XX This sets the A D conversion rate The valid rate values are 3 76 7 51 15 30 1 60 123 2 168 9 202 3 The next section ofthe sequence file is the acquisition loop section This section has the list of A D read operations that the driver will do This list of operations will be sequentially executed and repeated indefinitely The acquisition loop section must start with the LOOPSTART statement AII statements in the acquisition loop section cause a A D read operation to take place This means that the total acquisition loop time is approximately the A D conversion time plus a small amount of overhead The following statements can be used inthe acquisition loop PUSHDATA CC RR PUSHRDATA CC RR PUSHZERO RR PUSHTEMP TOSS CC RR CC is a channel number and can has range from 0 to 15 RR is arange specifier and can any of the following values 5V 2 5V 100MV 50MV and 25MV PUSHXXXX statements cause A D data channel number and range to be PUSHED onto the data FIFO The data FIFO is a first in first out buffer with each entry consisting of A D data the channel the data came from and the range setting The FIFO size is normally 64 entrys dee
6. 4A23 USER S MANUAL PRELIMINARY Copyright 1999 by MESA ELECTRONICS Richmond CA Printed in the United States of America All rights reserved This document and the data disclosed herein is not to be reproduced used disclosed in whole or in part to anyone without the written permission of MESA ELECTRONICS Mesa 4175 Lakeside Drive Suite 100 Richmond CA 94806 1950 Tel 510 223 9272 Fax 510 223 9585 E Mail tech mesanet com Website www mesanet com TABLE OF CONTENTS WARNINGS WARNINGS surn de RO pede Ida a ua Ou Aid 4 DESCRIPTION GENERAT aaa io 5 HARDWARE CONFIGURATION UO ADDRESS esee te kaa a CS RU EAR BEEN 6 SINGLE ENDED DIFFERENTIAL 5 6 CONVERSION RATE dada Le Ode odes dees ae pie Repo a a 6 INPUT CONNECTOR et tics ua e RA Ud a 4 A D OPERATION GENERAL e exp dex be Re ph Ee rn Rs pauco pee p pde 8 CONVERSION RATE etre 8 CALIBRATION dae as hake dew hee 9 ACCURACY A EE ae IEEE intend E EEEE EERE 9 4 23 SOFTWARE GENERAD aa dus AA a 10 AAI SII cit ea ada 10 4A23DRVR RECORD STRUCTURE 4 222025200554 Ra I EI sas 11 ZA23DRVREUNGTIOBNS vanadel tt 11 AA23DRVRRETURN CODES DO ea 14
7. IFO and displays it on the screen 4A23DRDM determines where to display the data by its channel number read from the FIFO 4A23DRDM is launched with the software interrupt number ofthe driver on the command line 4A23DRDM 60 Would launch the demo program and have the program use software interrupt 60H to communicate with the 4A23DRVR program Assuming that 4A23DRVR is not already loaded the full sequence of commands needed to run 4A23DRDM would be as follows 4A23DRVR 220 5 60 4A23DCFG SEQFILE 60 4A23DRDM 60 The assumptions here being that the 4A23 is located at the default 220H base I O location that IRQ5 is free and unencumbered and that software interrupt 60H is free The sequence file SEQFILE would of course have to contain some PUSHDATA or PUSHZERO or PUSHTEMP statements in its aquisition loop section for 4A23DRDM to display anything Page 17 4A23USERSMANUAL Page 18 4A23USERSMANUAL REFERENCE INFORMATION SPECIFICATIONS POWER SUPPLY Voltage Supply current no external load ISOLATED POWER Voltage Load current INPUT CHARACTERISTICS Input current Capacitance to system ground Isolation voltage Isolated Common mode dV dT Maximum input voltage ACCURACY Resolution Calibrated accuracy all ranges Gain TempCo MIN MAX UNIT NOTES 4 5 5 5 V 75 5 5 7 25 V 2 5 mA Loaded 1 1 nA at 25 C 50 pF 500 VDC 20 V uSec 3 6 V 20 bits 05 05 FSR 7
8. elta sigma design results in very high accuracy and linearity It does not suffer from the memory and creep problems common with integrating type A D chips The CS5526 A D has on chip calibration registers for full scale and offset This avoids the need for potentiometers and the problems that they bring These registers are loaded from the on card calibration EEPROM by the A D software when the input range is selected or changed This is necessary since the offset and full scale calibration values change with the input range selected Changes in conversion rate do not affect full scale or offset since they only change digital filter parameters The 4A23 has six input voltage ranges 5V 2 5V 1V 100mV 50 mV and 25 mV full scale The 5V range has 2 5V maximum negative input due to A D input amplifier common mode range limits Unipolar and bipolar input mode are supported by the 55526 A D chip but the supporting software and EEPROM calibration data only support bipolar operation for this revision 16 input channels are available for user inputs In addition a zero volt 2 5V reference and card temperature input can be selected for calibration thermocouple cold junction compensation T CONVERSION RATE The A D on the 4A23 can be programmed to do conversions at 8 different rates 3 76 Hz 7 51 Hz 15 Hz 30Hz 60Hz 123 2Hz 168 9Hz and 202 3Hz These rates double with the conversion rate jumper set to the high speed position A D input noise
9. following table shows the 4A23 base addresses for different jumper settings BASE ADDRESS W6 W7 0220H down down DEFAULT 0222H down up 0224H up up 0226H up up SINGLE ENDED DIFFERENTIAL INPUT The 4A23 can be configured with single ended or differential inputs If single ended input are chose there are 16 inputs available If differential inputs are chosen 8 differential inputs are available Differential inputs are suggested for low levelinputs or applications where the input cable is long Differential mode is selected by moving jumpers W2 W3 W4 and W5 to the up position Single ended mode is selected by moving W2 W3 W4 and W5 to the down position MODE W2 W3 W4 WS SINGLE ENDED down down down down DEFAULT DIFFERENTIAL up up up up CONVERSION RATE Jumper W1 selects the A D chips input clock and therefore the conversion rate When W1 is inthe down position the standard 32 768 KHz input clock is chosen This results in the standard 3 75 to 202 Hz A D conversion rate When W1 is in the up position a 65 536 KHz A D clock is used giving double the normal conversion rates This double speed option actually tends to have lower signal to noise ratios so is the default setting Page 6 10 CONNECTOR 4A23USERSMANUAL HARDWARE CONFIGURATION The 4A23 uses a 34 pin right angle male header for its analog input connector The suggested mating connector is AMP PN 746194 9 This is an IDC flat cable type connector The analog i
10. increases with conversion rate so lower rates are suggested for most applications Noise free resolutions with double speed enabled are approximately 7 51 Hz 18bits 15Hz 17 bits 30Hz 17 bits 60 Hz 16 bits 120 Hz 12 bits Page 8 4A23USERSMANUAL A D OPERATION CALIBRATION The 4A23 is calibrated at MESA but can be re calibrated if necessary To do a voltage only calibration requires that reference voltages of approximately 4V 2V 0 8V 0 08V 0 04V and 0 02V available The reference voltage source should be accurate to 50 PPM or better Calibration is performed via the program 4A23CAL EXE 4A23CAL is invoked with the hexadecimal port address ofthe 4A23 plus the optional T parameter if a temperature calibration is to be performed 4A23CAL 220 T 4A23CAL prompts you to connect different voltages to the input channel When 4A23CAL is done it will write the new calibration data into the 4A23 s EEPROM If the T option is specified 4A23CAL will do a temperature only calibration We do supply 4A23CAL to the user but strongly suggest that 4A23 card calibration be done at MESA ACCURACY The 4A23 has a basic accuracy limit of 05 This applies over the full operating temperature range of the card This accuracy assumes that the supplied 4A23 software is used to copy the EEPROM calibrate data from the 4A23 card into the A D chip registers The main source of error in the higher voltage ranges is temperature drift in the reference
11. lable status in Status field true data available false FIFO empty DrFuncGetFIFOO vflStatus 4 Return FIFO overflow status in Status field true FIFO has overflowed false no overflow Overflow status can be cleared by stopping the conversions and then restarting them DrFuncStartConversions 5 Start background data conversions DrFuncStopConversions 6 Stop background data conversions Also clears FIFO FIFO overflow status and scan count Page 12 4A23USERSMANUAL 4A23 SOFTWARE 4A23DRVR FUNCTIONS FUNCTION NUMBER DrFuncGetTemperature 7 Returns card temperature channel at 1 Vfull scale DrFuncGetFIFOData 8 Returns FIFO data FIFO channel and FIFO range in Data Channel and Range fields DrFuncGetScanCount 9 Returns the current scan count number of times around the data aquisition loop in the Data field DrFuncGetAtoDRecPtr 10 Return pointer to AtoD Record in Pointer segment and Pointer offset fields DrFuncGetCalibRecPtr 11 Return pointer to Calibrate Record Pointer segment and Pointer offset fields DrFuncSetConvRate 12 Sets the conversion rate Uses 32 bit value from 5526 PAS ADRateXX constants Page 13 4A23USERSMANUAL 4 23 SOFTWARE 4A23DRVR RETURN CODES The return code field of the Interrupt record indicates whether or not the function was successful or ifthe function failed why Return codes are as follows RETURN CODE MEANING 00 Successful completion 01 Failed 02 Bad parameter
12. nput connector pinout is as follows PIN RON N a ODO m 1 13 15 17 19 21 23 25 27 29 31 33 FUNC Sing Diff Input shield Input 0 0 Input 2 42 Input 4 4 Input 6 46 Input shield Input 8 0 Input 10 2 Input 12 4 Input 14 6 Input shield Input common 2 5V reference Input common M2 bit M4 bit Input shield PIN 2 10 12 14 16 18 20 22 24 26 28 30 32 34 FUNC Sing Diff Input shield Input 1 1 Input 3 3 Input 5 5 Input 7 7 Input shield Input 9 1 Input 11 3 Input 13 5 Input 15 7 Input shield Input common 2 5V reference Input common M3 bit Unreg 7 power Unreg 7 power Note that single ended analog inputs use Input common as their ground reference not Input shield The input shield connection is intended for use as an input guard only and may be several millivolts away from true input ground Input common should be used for differential input common mode reference The three isolated output bits M2 M3 M4 are 5V CMOS level output bits with input shield being the common return These outputs should not be loaded by more than 1 mA each since they are powered by the small isolation DC DC converter Page 7 4A23USERSMANUAL A D OPERATION GENERAL The 4A23 uses a Cirrus 55526 The 55526 is a 20 bit delta sigma A D converter This converter has low power requirements and a serial interface that make it suitable for the 4A23 s isolated input design The d
13. o select the range in the 55526 A D chip These listed in the 5526 PAS file in the source section of the distribution disk When status is returned true status is represented by an OFFH byte in the status field and false status by a 00 in the Status field When A D data is returned the data is just as read from the converter except that it is sign extended to 32 bits The record structure is as follows DATA DATA SIZE BYTE OFFSET Function number byte 0 Return code byte 1 Status byte 2 Pointer offset word 16 bits 3 Pointer segment word 16 bits 5 Data longint 32 bits 7 Channel byte 11 Range longint 12 4A23DRVR FUNCTIONS These are determined by the function number in the Function number field ofthe data record The following is a list and brief description of the driver functions For more information on the 4A23DRVR functions you should refer to the 4A23DRVR source code in the SOURCE directory of the 4A23 distribution floppy Applicable files are 4A23DRVR PAS 4A23LOW PAS and 4A23DFUN PAS 4A23DLOW PAS Page 11 4A23USERSMANUAL 4A23 SOFTWARE 4A23DRVR FUNCTIONS FUNCTION NUMBER DrFuncGetVersion 0 Returns Version in Data field DrFuncGetConvStatus 1 Returns converter running status is Status field running true stopped false DrFuncGetDriverStatus 2 Return configuration status of driver is Status field true configured false not configured DrFuncGetFIFODataStatus 3 Return FIFO data avai
14. p The advantage of this FIFO structure is that the time sequence of the A D data is not lost as long as the user program does not let the FIFO overflow PUSHDATA is the normal way to read A D data PUSHRDATA is the same as PUSHDATA but revereses the input leads This only applies to differential inputs PUSHRDATA will do exacly the same thing as PUSHDATA with single ended inputs PUSHZERO pushes an A D reading at the specified range with the inputs grounded This can be used for autozeroing the 4A23 in applications where the factory preset zero is not close enough PUSHTEMP pushes an A D reading at 1V full scale of the temperature output pin or the reference chip TOSS statements read the A D and simply discard the data They can be used for a No Op time delay in the aquisition loop Page 15 4A23USERSMANUAL 4A23 SOFTWARE SEQUENCE FILE FORMAT Here is an example of a sequence file that sets the conversion rate to 15 conversions per second reads channels O though 3 at 5V full scale channels 4 through 7 at 1 V full scale does two zero reads at 5V and IV anda temperature read SETRATE 15 LOOPSTART PUSHDATA 0 5V PUSHDATA 1 5V PUSHDATA 2 5V PUSHDATA 3 5V PUSHDATA 4 1V PUSHDATA 5 1V PUSHDATA 6 1V PUSHDATA 7 1V PUSHZERO 5V PUSHZERO 1V PUSHTEMP Page 16 4A23USERSMANUAL 4 23 SOFTWARE 4A23DRDM 4A23DRDM is a simple demonstration program of the 4A23 card amp 4A23DRVR combination 4A23DRDM reads data from the drivers F
15. ranges 25 mV 50 mV 100 mV 1V 2 5V and 5V full scale All ranges except the 5V range be bipolar A D input is conditioned with a chopper stabilized instrumentation amplifier for minimum offset drift lt 50 nV C A high quality reference is used to insure overall gain stability of 7 PPM C Conversion rate can be programmed from 3 76 Hz to 202 Hz with higher rates trading off conversion rate for noise The 4A23 can berunin polled or interrupt driven modes allowing background data acquisition Interrupts 2 3 4 5 7 10 11 or 12can be used Allcalibration information is stored in an on card EEPROM so no zero or full scale calibration potentiometer are needed The low overall power consumption 300mW reduces thermocouple induced offsets that can cause problems in lower input ranges An on card temperature sensor is available for thermocouple cold junction compensation The 4A23s reference voltage is brought out to the input connector for ratiometric type applications Driver software for background data collection is provided as is source code for driver and example programs Page 5 4A23USERSMANUAL HARDWARE CONFIGURATION ADDRESS The 4A23 card uses 2 contiguous addresses in I O space The 4A23 base address has 4 optional locations These are set with jumpers W6 and W7 Jumper blocks W6 and W7 are three pin headers with two valid jumper positions up and down Up means away fromthe J1 and J2 bus connectors The
16. this information service data or shipping instructions will be forwarded to you 2 On receipt of the shipping instructions forward the product in its original protective packaging transportation prepaid to Mesa Electronics Repairs will be made at Mesa Electronics and the product returned transportation prepaid THE FOREGOING WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY OF MERCHANTABILITY FITNESS OR ADEOUACY FOR ANY PARTICULAR PURPOSE OR USE MESA ELECTRONICS SHALL NOT BELIABLE FOR ANY SPECIAL INCIDENTAL OR CONSEOUENTIAL DAMAGES WHETHER IN TORT OROTHERWISE Page 21 4A23USERSMANUAL REFERENCE INFORMATION Page 22 4A23USERSMANUAL REFERENCE INFORMATION SCHEMATIC DIAGRAMS Page 23 4A23USERSMANUAL Page 24 4A23USERSMANUAL Page 25 4A23USERSMANUAL Page 26
17. voltage The main source oferror in the lower ranges is parasitic thermocouple voltages from small temperature differentials in semiconductors in the input path Thermocouple offsets can be minimized by mounting the 4A23 away from sources ofheat The temperature channel is mainly for internal use and calibration is only guaranteed to be accurate to 5 C Page 9 4A23USERSMANUAL 4 23 SOFTWARE GENERAL The 4A23 uses a TSR driver program to access the 4A23 hardware This driver hides may of the details of accessing the 4A23 making the data acquisition application programs task easier The driver uses the EEPROM calibration data to calibrate the A D data The driver allows data acquisition to be done as a background interrupt driven task with the acquired data saved in a driver maintained FIFO The standard FIFO size is 64 entries deep This means that the foreground task can easily poll keyboards do disk I O or other tasks without interfering with the data acquisition sample rate 4A23DRVR The TSR driver is called 4A23DRVR EXE 4A23DRVR is launched with three command line parameters These parameters are the 4A23 base address the hardware interrupt number that the 4A23 will use and the software interrupt number used for communication with the driver For example 4A23DRVR 220 5 60 Would launch the driver with a 4A23 base address of 220H a hardware interrupt number of 5 and asoftware interrupt number of 60H Note that the base
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