Overview Of Communications Methods; Introduction - Omron E5CN-H Communications Manual

SECTION 1 Communications Methods

1.1 Overview of Communications Methods

■ Introduction

1-2
The program for the communications functions are created on the host
(personal computer, PLC, or other type of communications master), and the
E5CN/AN/EN-H's parameters are monitored or set from the host. Therefore,
the description provided here is from the viewpoint of the host.
CompoWay/F is OMRON's standard communications format for general serial
communications. This format uses a standard frame format as well as the
well-established FINS* commands used for OMRON's PLCs. Therefore, it can
simplify communications between components and the host.
*FINS (Factory Interface Network service)
The FINS protocol provides message communications between controllers in
OMRON FA networks.
Modbus is a standard communications control method that conforms to the
Modicon Company's RTU-mode Modbus Protocol (PI-MBUS-300 Revision J).
Modbus is a registered trademark of Schneider Electric.
It supports functions equivalent to the CompoWay/F Read Variable Area,
Write Variable Area, Operation Command, and Echoback Test functions.
The E5CN/AN/EN-H supports the following communications functions.
• Reading/writing of parameters
• Operation instructions
• Selection of setup levels
Communications are subject to the following condition:
• Parameters can be written only when the Communications Writing parameter
is set to ON (enabled).