Tag Archives: Modbus RTU Click PLC Master to BRX PLC Slave Communication

Modbus RTU Click PLC Master to BRX Do-More Slave

We will now use Modbus RTU to connect a Click Master to a BRX Do-More Slave controller.  Recently I was asked to demonstrate communication between a Click PLC and BRX Do-More PLC using Modbus RTU. Both PLCs are available from automation direct com. Modbus serial communication (Modbus RTU) is a standard protocol used in many automation devices. It works on a Master / Slave configuration. You can have only one master per network on Modbus RTU (Remote Terminal Unit). A maximum of 32 devices (Nodes) on the network can communicate to the master. A review of the Modbus RTU protocol (RTU frames) can be seen at the following URL.
http://www.rtautomation.com/technologies/modbus-rtu/
Using the Click PLC as a Master we will be communicating to the BRX Do-More PLC (Slave). Our example will read 10 registers from the BRX Do-More PLC and write 10 registers to the Click PLC. Let’s get started! Keep on Reading!