Measurement Computing GPIB-488 - Manual (Page 40)

Chapter 3 GPIB 488.1 Library Reference
GPIB-488 3-27 Programming Reference Manual
IBLN
Check that a device is present on the bus.
Syntax
C ibln (int board, int pad, int sad, short* listen)
Parameters
board is the board or device handle.
pad is the primary address of the GPIB device (0-30).
sad is the secondary address of the GPIB device (96-126 or 0x60-0x7e) or one of the constant
values NO_SAD or ALL_SAD.
listen is the variable that the result is returned to.
Returns
ibsta will contain a 16-bit status word as described in Appendix B, IBSTA .
iberr will contain an error code if an error occurred.
listen will contain 0 if no listener is found. Contains non-zero if a listener is found.
Usage Notes
Set sad = NO_SAD (0) if the device does not have a secondary address.
Set sad = ALL_SAD (-1) if you do not know the device’s secondary address and you want
all possible secondary addresses to be tested.
Example
This example tests for the presence of a device with a GPIB address of 4.
C int board, listen;
board = ibfind (“GPIB0”);
ibln (board, 4, NO_SAD, &listen);