Using The Programming IDE / Resources / Networks
Modbus TCP
ModbusTCP functionality includes reading or writing to Modbus Holding Registers (4:xxxx registers in Modbus syntax).
Server
External ModbusTCP clients can have read/write access to your User Program Variables. You declare which of your variables can be accessed and the relative address offset from 4:0000 the data will appear.
Client
This function is reserved for future use.