Using Modbus To Enable The Gx/Gp To Read Data From And Write Data To Other Devices (Modbus Master Function); Setting Serial Communication Conditions; Configuring The Modbus Master Function; Setting Commands - YOKOGAWA GX20 User Manual

4.4 Using Modbus to Enable the GX/GP to Read
Data from and Write Data to Other Devices
(Modbus master function)
4.4.1

Setting Serial Communication Conditions

Description
4.4.2

Configuring the Modbus Master Function

Description
4.4.3

Setting Commands

Description
IM 04L51B01-01EN
The GX/GP can operate as a Modbus master device.
The GX/GP can connect to another device (Modbus slave device) via Modbus and
read from and write to the device's internal registers. Read data can be handled using
communication channels. Data that can be written are I/O channel data, math channel data,
and communication channel data.
Modbus master
GX/GP
Serial communication
Modbus slave device
• Configure the receiver function
• Set data transfer conditions
For details on the settings, see page 1-198 in section 1.22.1, "Setting Basic Communication
Conditions".
• Enable the master function
• Set communication conditions
• Set the recovery action
For details on the settings, see page 1-200 in section 1.22.2, "Enabling or Disabling the
Modbus Master Function (/MC option) and Setting Communication Conditions".
For details on the Modbus functions and registers that the GX/GP supports, see page 4-11 in
section 4.5, "Modbus Function and Register Assignments".
• Set the master command number
• Set the command
For details on the settings, see page 1-201 in section 1.22.3, "Setting Modbus Master
Transmission Commands".
For command setting examples, see page 4-4 in section 4.2.4, "Setting Commands".
Slave device internal register
Command
Input register
Read
3XXXXX
Read
Hold register
Write
4XXXXX
GX/GP
Read
Read
App
Write
Index
4-9
1
2
3
4
5