The Gateway has one one RS485 port.
RS485
The baudrate range for RS485 port (/dev/ttyUSB0) is 600 bps to 460800 bps. Note that with a longer cable, the maximum speed may drop. It is recommended to use special cables designed for RS485. The port is protected by high-power TVS diodes against electrical surges.
Modbus RTU
The gateway supports most protocols operating on the physical RS485 interface. For the most popular Modbus RTU protocol, the gateway has a built-in proprietary application that allows you to easily configure any device operating under this protocol and send data to a server using MQTT, TCP/IP or HTTP. To use other protocols you need to install additional applications.