Chapter 5
S Mode Functions — ppc
©
National Instruments Corporation
5-27
ppc
Parallel Poll Configure
Type
Parallel poll function
Syntax
ppc addr,ppr,s [addr,ppr,s]...
<CR>
Purpose
You can use
ppc
to configure specified GPIB devices to respond to parallel polls in a certain
manner.
Remarks
The argument
addr
specifies the GPIB address of the device to be enabled for parallel polls.
addr
consists of a primary address and an optional secondary address.
The argument
ppr
is an integer string between 1 and 8 which specifies the data line on which
to respond.
The argument
s
is either 0 or 1 and is interpreted along with the value of the device’s
individual status bit to determine whether to drive the line true or false.
Each group of
addr,ppr,s
can be separated by either a comma or space, just as any list of
arguments.
If this is the first function you call that requires GPIB Controller capability, and you have not
disabled System Controller capability with
rsc
, the GPIB-232/485CT-A sends Interface
Clear (IFC*) to make itself CIC. It also asserts Remote Enable.
If you passed control to some other GPIB device, control must be passed back to you or you
must send IFC* to make yourself CIC before making this call. Otherwise, the ECIC error is
posted.
The GPIB-232/485CT-A takes the arguments
ppr
and
s
and constructs the appropriate
parallel poll enable (PPE) message for each
addr
specified.
If you call
ppc
without an argument, the GPIB-232/485CT-A records the EARG error.
If only one
addr
,
ppr
,
s
is specified, and
addr
has the special value of 255 (hex FF), the
GPIB-232/485CT-A configures itself for parallel polls. To do this, the GPIB-232/485CT-A
must be using IEEE 488 Parallel Poll (PP) interface function subset PP2. You can do this by
setting the PP2 option using the
conf
function. If the PP2 option is not set, the
