The Modbus RTU gateway is set folllowing serial data format and baudrate (these settings are not configurable) :
RS485 MODBUS ports are 2-wire operating with an asynchronous serial data format:
1 start bit / 8 data bits / 1 stop / no parity (1,8,1,N) - transmitted at 9600 baud.
Refer to page 3 of the General Description manual for a full description of communication format.