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JAVA agent for MODBUS4J
Developing JAVA code to communicate with Modbus devices/controllers present in it's network using MODBUS4J.
By vijay chelliah on 28 May, 2019 - 2:07 am

I need to develop a JAVA agent code which will communicate with Modbus devices/controllers present in it's network using MODBUS4J.

I have a question regarding how should i designate my code whether as a Master of slave. If master, can a network have multiple masters? And if a slave, can a slave get readings from master controllers (which in turn has all other slave's readings)?

By James Ingraham on 29 May, 2019 - 3:05 pm
1 out of 1 members thought this post was helpful...

Modbus/TCP uses slightly different terminology. A Modbus server is generally a slave, and a client is a master. There are devices that can be both. Typically, your Java app will be a client / master. While there can be many clients / masters on one network, there are issues when one server / slave has more than one client / master. Basically, you can have multiple clients reading data, but if you've got multiple clients writing data then someone's commands are going to be over-ridden. Note that some devices only allow one client, but this is rare.

-James Ingraham
Sage Automation, Inc.