Omron CJ1W-SCU32 Operation Manual page 139

Modifying Standard System Protocols
When you connect OMRON devices, if there is no standard system protocol or you wish to modify
part of the protocol, use the CX-Protocol to modify the standard system protocol, transfer this as a
separate communications sequence to the Serial Communications Unit, and execute the ExecP-
MCR instruction.
CPU Unit
ExecPMCR
Sequence
number
Memory used for
CJ-series Units
Creating a New Protocol
When you connect a general-purpose external device that has an RS-232C or RS-422A/485 port,
use the CX-Protocol to create a new protocol that contains the communications specifications for the
general-purpose external device, transfer these specifications to the Serial Communications Unit,
and execute the ExecPMCR instruction.
CPU Unit
ExecPMCR
Sequence
number
Memory used for
CJ-series Units
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
Modifying and transferring
standard system protocols
Serial Communications Unit
Modified standard
system protocol
Sequence No.
specification
Step 0
Step 1
Step 2
Shared memory
I/O refreshing
Creating and transferring a new protocol
Serial Communications Unit
Newly created protocol
Step 0
Sequence No.
specification
Step 1
Step 2
Shared memory
I/O refreshing
4 Using Protocol Macros
Command execution Send, Recv, Send&Recv
Messages
RS-232C or RS-422A/485
General-purpose external device
Command execution Send, Recv, Send&Recv
Messages
RS232C or RS-422A/485
General-purpose external device
4
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