Introduction - Omron SYSMAC CS1W-RPT01 Operation Manual

Introduction

6-1 Introduction
Message service
Source PLC to PLC
node to
destination
node
PLC to
computer
Computer
to PLC
168
A message service is a command/response system used for data transmis-
sion between nodes on a network, i.e., PLC to PLC, PLC to computer, and
computer to PLC). The message service can also be used to control opera-
tions, such as mode changes. The message service is implemented by send-
ing commands from the user program. The following communications
instructions are used:
SEND and RECV: Instructions for sending and receiving data.
CMND: An instruction for sending FINS commands. Some FINS commands
are supported by Controller Link Units, and other FINS commands supported
by the PLC's CPU Unit.
SEND/RECV instructions
C200HX/HG/HE,
C200HX/HG/HE,
CS/CJ-series, CVM1,
CS/CJ-series, CVM1,
CV-series, or
CV-series, or
CQM1H-series PLC
CQM1H-series PLC
SEND
User program
A program is not required for receiving
responses when the PLC executes
SEND and RECV.
C200HX/HG/HE,
CS/CJ-series, CVM1,
CV-series, or CQM1H-
series PLC
Command
SEND
(The equivalent of SEND/
RECV and CMND are sent
from the computer pro
gram.)
CMND instruction (FINS commands)
CS/CJ-series, CVM1,
CV-series, or
CQM1H-series PLC
(Not supported by the
C200HX/HG/HE.)
(Com-
mand for
CPU Unit)
CMND
User program
A program is not required for receiving
responses when the PLC executes
commands.
Computer
A program is required for sending and
receiving data with the computer.
A program is not required for receiving
responses when the PLC executes commands.
C200HX/HG/HE,
Computer
CS/CJ-series, CVM1, CV-series
or CQM1H-series PLC
Command
Programming is required to receive
responses at the computer.
Section 6-1
C200HX/HG/HE,
CS/CJ-series, CVM1,
CV-series, or
CQM1H-series PLC
(Com-
mand for
Controller
Link Unit)
Command
(Com-
mand for
CPU Unit)
Command
(Command for
Controller Link
Unit or CPU
Unit)