The Industrial Raspberry Pi Forum

Hi,

I'm investigating the suitability of Revolution Pi for a small project. Components communicate via ModbusRTU over rs485. Reading through some of the materials indicate that the recommended way to operate a RevolutionPi as Modbus master is to use a USB to RS485 converter. This seems like a sub optimal approach.

What's wrong with using the Modbus gateway module? The website mentions that the gateway can be used when the usb to RS485 converter is undesirable. When would this be desirable?

What are the disadvantages to using the Modbus gateway module?

Hi ttxndrx, you can use the RevPi Connect instead as it has a RS485 interface included. So you don't need any extra USB hardware.
The Virtual RevPi Modbus Modules have the advantage that they can used as master or as slave.
The Modular Gateway Modbus RTU Slave is part of a product family that existed before the RevPi.

Two Gateway Components can be connected as a Modular Gateway Module so you can transfer up to 512 byte of input and 512 bytes of output data between them.
They are certified fieldbus slave modules.

The advantage of the Gateway Modules is that they are certified fieldbus slave components that connect to the process image. So you can write your application and don't have
to take care about fieldbus specific application tasks.