User`s manual

GFK-2334A A-1
COMMREQ Operation
The Communication Request function (COMMREQ) allows the program to communicate
with a GE Fanuc intelligent module, such as a PROFIBUS master or slave.
The COMMREQ function uses a command block that contains the data to be
communicated to the device, plus information related to the execution of the COMMREQ.
The command block must be placed in the designated memory area using data move
instructions, such as MOVE or BLKMOV (Block Move).
The CPU reports the result of the COMMREQ in the status word, which is a single
location in PLC data memory. The status word address is specified in the command block.
For a list of status codes reported in the status word, see “COMMREQ Status Word” on
page A-5.
For details on the COMMREQ tasks supported by the PROFIBUS CPUs, see:
 CPU366 with PROFIBUS Master, chapter 5
 CPU367 with PROFIBUS Slave, chapter 6
This appendix provides an overview of the COMMREQ instruction. For details of the
COMMREQ ladder instruction, refer to the online help provided with the programming
software.
A
Appendix