Each MODBUS controller will have specific requirements for configuration. You will need to refer to the documentation specific to the equipment you are using.
Apply the settings according to the requirements of the MODBUS controller.
The communication settings for the SPX Wellhead always use Serial, RTU mode, 8 data bits, even party, and one stop bit, and transfers data in Big Endian. The MODBUS registers do not provide a means of changing any of these communication settings.
Using the Register Map in Section 4.4, enter the desired register addresses.
Once you have entered the register map, you can start issuing function codes or set up a polling schedule. See section 4.3 for supported MODBUS functions.