National Instruments GPIB-PC Network Card User Manual


 
BASICA/QuickBASIC GPIB-PC Function Calls Section Four A
GPIB-PC User Manual 4A-70 ©National Instruments Corp.
BASICA/QuickBASIC BASICA/QuickBASIC
IBRSV IBRSV
Purpose: Request service and/or set or change the serial poll status
byte
Format: CALL IBRSV (BD%,V%)
Remarks: BD% specifies an interface board. V% specifies the response
or status byte the GPIB-PC provides when serially polled
by another device that is the GPIB CIC. If bit 6 (the &H40
bit) is set, the GPIB-PC additionally requests service from
the Controller by asserting the GPIB SRQ line.
The IBRSV function is used to request service from the
Controller using the Service Request (SRQ) signal and to
provide a system dependent status byte when the Controller
serially polls the GPIB-PC.
When IBRSV is called and an error does not occur, the
previous value of ist is stored in IBERR%.
Refer also to Table 2.1.
Board Examples:
1. Set the Serial Poll status byte to &H41, which simultaneously
requests service from an external CIC.
100 V% = &H41
110 CALL IBRSV (BRD0%,V%)
2. Change the status byte as in Example 1, without requesting
service.
100 V% = &H01 ' New status byte value.
110 CALL IBRSV (BRD0%,V%)