Measurement Computing GPIB-488.2 - Manual (Page 25)

GPIB 488.2 Porting Guide 986992
IOtech to Associated MCC APIs 3-7
IOtech GPIB Command Associated MCC GPIB 488.2 Command
ControlLine TestSRQ
Limited functionality
Syntax
ControlLine INT WINAPI ControlLine(DevHandleT devHandle);
TestSRQ TestSRQ(int board, short *result)
Usage Notes
ControlLine, no longer to be used. The ControlLine command could only be used only
on IEEE 488 devices. This command returned the status of the IEEE 488 bus control lines as
an 8-bit unsigned value (bits 2 and 1 were reserved for future use), as indicated in the table.
Bit 8 Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1
EOI SRQ NRFD NDAC DAV ATN 0 0
TestSRQ Is used to evaluate state of the SRQ line. TestSRQ does not alter the state of the
SRQ line. In the example, we test to see if SRQ is asserted.
Example:
Short result;
TestSRQ (0, &result);
if (result == 1)
{ /* SRQ is asserted */}
else
{ /* No SRQ at this time */}