Measurement Computing GPIB-488 - Manual (Page 65)

Chapter 3 GPIB 488.1 Library Reference
Programming Reference Manual 3-52 GPIB-488
IBWRT
Writes data from a string to the specified device or GPIB Interface Board.
Syntax
C ibwrt (int boarddev, char buf[], unsigned long
bytecount)
Parameters
boarddev is an integer containing the board or device handle.
buf is the string containing the data to be written. buf can contain up to 4 gigabytes-1 (2 32 -1
bytes). String size may be limited by the language you are using. Check documentation for
your language.
bytecount specifies the number of bytes to be written from the string.
Returns
ibsta will contain a 16-bit status word as described in Appendix B, IBSTA .
iberr will contain an error code of the first error detected, if an error occurred. An EADR
results if boarddev specifies a board and the board has not already been addressed to talk.
ibcnt , ibcntl will contain the number of bytes that were written. ibcnt is a 16-bit integer.
ibcntl is a 32-bit integer. If the requested count was greater than 64 K, use ibcntl instead
of ibcnt .
Usage Notes
This routine is used to send device-specific commands. A write terminates when one of the
following occurs:
• All bytes are transferred.
• An error is detected.
• The time limit is exceeded.
• A DCL (Device Clear) or SDC (Selected DC) is received from the CIC.
• All data is sent.
If boarddev specifies a device, the specified device is addressed to listen and its associated
access board is addressed to talk. If boarddev specifies a GPIB Interface Board, the
Controller-In-Charge must have already addressed a device as a listener and the board as a
talker. If the board is the Active Controller, it unasserts ATN in order to send data. This routine
leaves the board in that state.