5 MODBUS RTU Protocol communication
CP340/CP341/CP440/CP441 Communication and Programming
Entry-ID: 88867653, V1.0, 02/2014
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3. Invoke FB180 function block .
Fig. 122: Invoke FB180 function block
5.4.4
Equipment connection
Use standard RS232C cable to connect serial ports of CP341 and computer. The
detailed cable connecting method may be seen in CP341 Manual - Chapter B:
Connecting cables.
5.4.5
Communication test
Download the hardware configuration and program into CPU. Open the software
Modscan32 in the computer, and click Connection
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〉
Connect in Modscan32 to
display the following screen. Select the used serial port, and set Baud rate, data
bit, stop bit and check mode, and select a communication protocol according to the
applicable connection. After setting completes, click OK to display the monitor
screen.