JAVA agent for MODBUS4J


Thread Starter

vijay chelliah

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)?

James Ingraham

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.