How to use Solidot Slice XB6S-MT2002 and XB6S-C01SP to implement Modbus TCP to Modbus RTU communication

This case uses Solidot's remote I/O Slice XB6S Modbus TCP coupler XB6S-MT2002 with serial communication module XB6S-C01SP to read/write Modbus RTU slaves.

Enter the IP address of XB6S-MT2002 (192.168.1.120) in a browser to access its web interface. Open Configuration Info to view the addresses occupied by XB6S-C01SP: Read Data Address and Write Data Address.

Click on XB6S-C01SP to enter its configuration interface.

1. Set Communication Mode to Modbus RTU Master, with parameters 9600-N-8-1.

1. Configure node parameters:

   • Slave ID: 1

   • Start Address: 0

   • Read/Write: 2 consecutive registers

1. Click Submit. A "√ Success" indicates successful parameter deployment.

1. Use Modbus Poll to monitor Read/Write Data Addresses.

1. Use Modbus Slave to simulate an RTU slave device.

1. Write 1A, 2B to the first two Write Data Addresses. These values will be transmitted to the slave and displayed in the first two Read Data Addresses.

Byte Order Handling:

• Modbus TCP uses big-endian (high byte first)

• Modbus RTU uses little-endian (low byte first)
  → Configure 2-byte swap mode in XB6S-C01SP (disconnect Modbus Poll before submitting parameters).

1. Data read/write operations will now function correctly.