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National Instruments GPIB-PC User Manual

Page 188

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Section Four A

BASICA/QuickBASIC GPIB-PC Function Calls

©National Instruments Corp.

4A-113

GPIB-PC User Manual

CMD$ = CHR$(&H19) : CALL IBCMD (BRD0%,CMD$)
IF IBSTA% < 0 THEN GOSUB GPIB-ERROR:

REM
REM Since the DVM and GPIB-PC are
REM still addressed to talk and listen,
REM the measurement can be read as follows.
REM

RD$ = SPACE$(16) : CALL IBRD (BRD0%,RD$)
IF IBSTA% < 0 THEN GOSUB GPIB-ERROR:

REM
REM To close out a programming sequence,
REM send IFC to initialize the bus and
REM call the IBONL function to place the
REM GPIB-PC offline.
REM

CALL IBSIC (BRD0%)
V% = 0 : CALL IBONL (BRD0%,V%) : STOP
END

FIND-ERROR:
REM A routine at this location would
REM notify you that the IBFIND call
REM failed, and refer you to the
REM handler, software configuration
REM procedures.
PRINT "IBFIND ERROR" : STOP

GPIB-ERROR:
REM An error checking routine at this
REM location would, among other things,
REM check IBERR to determine the exact
REM cause of the error condition and
REM then take action appropriate to
REM the application. For errors during
REM data transfers, IBCNT may be
REM examined to determine the actual
REM number of bytes transferred.
PRINT "GPIB ERROR" : STOP

DEVICE-ERROR:
REM A routine at this location would
REM analyze the fault code returned in
REM the DVM's status byte and take
REM appropriate action.
PRINT "DVM ERROR" : STOP
END