November 1985
National Instruments
If you call ppc without an argument, the GPIB-MAC
records the EARG error.
If this is the first function you call that requires
controller capability, and you have not disabled System
Controller capability with rsc, the GPIB-MAC sends
Interface Clear
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 will be posted.
The GPIB-MAC takes the arguments ppr and s and
constructs the appropriate parallel poll enable
message for each addr specified.
When addr is the address of the GPIB-MAC, the
MAC programs itself to respond to a parallel poll by
setting its local poll enable (lpe) message to the value
specified.
Refer also to ist, ppu, rpp, and to Appendix F on
parallel polling.
Example:
‘Configure 2
‘devices for parallel poll.
PRINT # 1
‘Conduct a
poll of 2
‘devices configured above.
(both devices responded
positively)
LINE INPUT
,RESP$
‘Assign parallel poll response to
‘integer variable.
55
SECTION FOUR FUNCTIONS