Manual

4-1
IM 04L51B01-01EN
Using Modbus Functions (Communicating with Modbus devices)
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App
4.1 Using Modbus/TCP to Enable Other Devices to
Read Data from and Write Data to the GX/GP
(Modbus server function)
The GX/GP can operate as a Modbus server.
Other devices (Modbus client devices) can carry out the following operations on the GX/GP.
Read I/O channel and math channel (/MT option) data
Read communication channel (/MC option) data
Write data to communication channels
Start and stop recording, write messages, and perform other operations
Load the recording start/stop condition, message strings, and other types of data
Modbus client device
GX/GP
Modbus server
Ethernet
Command
Input register
Hold register
Read
Write
Read
3XXXXX
4XXXXX
Write
Read
Read
GX/GP internal register
Client
4.1.1 Setting Basic Network Communication Conditions
Description
Obtain the IP address automatically
Set the IP address manually (when automatic IP address assignment is set
to Off)
For details on the settings, see page 1-123 in section 1.16.1, “Setting Basic Communication
Conditions”.
4.1.2 Configuring the Modbus Server Function
Description
Enabling the Modbus Server Function
For details on the settings, see page 1-136 in section 1.16.9, “Setting the Server Functions to
Use (FTP, HTTP, SNTP, MODBUS, GENE)”.
Applying Modbus Connection Limits
Set this function to limit the IP addresses that can connect to the GX/GP Modbus server
function.
You can register up to 10 IP addresses.
For details on the settings, see page 1-136 in section 1.16.8, “Limiting the Connection to the
Modbus Server (GX/GP)”.
Chapter 4 Using Modbus Functions (Communicating with Modbus devices)