Host Link Communications - Omron CJ - PROGRAMMING MANUAL 08-2008 Programming Manual

Serial Communications
6-3-1

Host Link Communications

Command flow Command type
Host computer
Host link command
PLC
Host link command
FINS command
(with host link header
and terminator)
Header
PLC
FINS command
(with host link header
Host computer
and terminator)
Header
Note
The following table shows the host link communication functions available in
CS/CJ PLCs. Select the method that best suits your application.
Communications method
Create frame in the host com-
puter and issue command to the
PLC. Receive the response from
the PLC.
Application:
Use this method when communi-
cating primarily from the host
computer to the PLC.
Create frame in the host com-
1
puter and issue command to the
PLC. Receive the response from
the PLC.
Application:
FINS
Use these methods when com-
municating primarily from the
Terminator
host computer to PLCs in the
network.
Issue frame with the CPU Unit's
2
SEND/RECV/CMND instruc-
tions. Receive response from the
host computer.
Application:
FINS
Use this method when communi-
cating primarily from the PLC to
Terminator
the host computer to transmit
status information such as error
information.
1. The FINS command must have a host link header and terminator attached
before it is transmitted from the host computer.
Configuration
Directly connect the host computer in a 1:1
or 1:N system.
OR
Directly connect the host computer in a 1:1
or 1:N system.
OR
Communicate with other PLCs in the
network from the host computer. (Convert
from host link to network protocol.)
Command
Directly connect the host computer in a 1:1
system.
Command
Communicate with the host computer
through other PLCs in the network. (Convert
from host link to network protocol.)
Command
Section 6-3
Command
Command
SEND/RECV/
CMND
SEND/RECV/
CMND
293