5 MODBUS RTU Protocol communication
CP340/CP341/CP440/CP441 Communication and Programming
Entry-ID: 88867653, V1.0, 02/2014
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Fig. 60: Selecting communication protocol
4. Double-click the envelop icon under Protocol to configure MODBUS Slave
parameter, and click MODBUS-Slave button.
Fig. 61: Configure MODBUS Slave communication parameter
Step 1: set MODBUS Slave address, which is set as 2 in this example
Step 2: set parameters of MODBUS Slave, such as Baud rate, stop bit and check
bit, etc.
Then configure the parameters represented by the function codes. For details, see
the four figures below.
5. FC01,05,15: status of read and forced output bit. The left side is info transfer
address, and the right side is corresponding PLC address area, viz. the left
addresses from 0 to 100 match MODBUS address area 00001 to 00101, and the
Step 1
Step 2