Can Read Value in Modbus but cannot write value in Modbus

Hello, has anyone managed to write values ​​using modbus using the GRV-CSERI-4 serial on YOKOGAWA YS1700 devices. For now, I can only read values ​​from serial modbus but cannot write values ​​into YOKOGAWA’s Modbus via GRV-CSERI-4. can anyone help me? I have tried many ways but still not successful.


I also face the issues same like this person

Are you using PAC Control? Are you using the Modbus kit? If so, what does it return in the status variable after you attempt a write? What function code are you using to write with (6 or 16)?