GPIB-PC Functions — Introduction
Section Three
GPIB-PC User Manual
3-10
©National Instruments Corp.
IBFIND (bdname,bd)
This is the same as the Group I function except that boards are assigned
names at configuration time in the form
GPIBn
, where
n
is a board's
decimal number (0, 1, 2, ...) within the computer. For instance, in a
system with two GPIB boards, the first is named
GPIB0
and the second
GPIB1
.
IBCMD (bd,buf,cnt)
and
IBCMDA (bd,buf,cnt)
Both functions use the specified board to write commands from memory
to the GPIB. The messages are sent synchronously using
IBCMD
and
asynchronously using
IBCMDA
. These command functions are used, for
example, to address and unaddress GPIB devices and to send interface
messages that enable and disable devices for serial and parallel polls,
that clear and trigger devices, and that lock out front panel control of
devices.
IBRD (bd,buf,cnt)
and
IBRDA (bd,buf,cnt)
Both functions use the specified board to read from a device that has
already been addressed to talk (for example, by the
IBCMD
or
IBCMDA
function). The syntax for these low-level functions is the same as their
high-level counterparts of Group I and III. The software automatically
differentiates bd descriptors that refer to devices from those that refer to
boards, and executes the read operations appropriately.
IBRDI
and
IBRDIA
are also available in BASIC for binary transfers to
an integer array.
