5 MODBUS RTU Protocol communication
CP340/CP341/CP440/CP441 Communication and Programming
Entry-ID: 88867653, V1.0, 02/2014
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5.4.2
Configuration
1. Open the project ptp that has been created, insert a new SIMATIC 400 Station,
and change the station name to CP441-2 modbus Slave.
2. Double-click Hardware to enter the hardware configuration interface, and insert
RACK, PS, CPU, and CP441-2. Please refer to the forgoing chapters for specific
steps.
3. In the CP441-2 module, click Parameter to configure CP441-2 parameters, and
select MODBUS Slave in Protocol options.
Fig. 112: Selecting communication protocol
4. Double-click the envelop icon under Protocol to configure MODBUS Slave
parameter:
Fig. 113: Configure MODBUS Slave communication parameter
5. Set the basic parameters such as communication rate and message details,
etc. In this example, the slave address is set as 100 (the default setting is 222, with
value range from 1 to 255). Then enter the slave function code configuration
interface. The detailed information is seen below: