Required Arduino Model which supports MODBUS TCP and RTU (RS485)

Hello Friends,

I am new here. I want to use Arduino as a Modbus Client/Server over TCP and RTU.

Please tell me the best suitable model in Arduino and also mention if I need any other extra accessory for this.

Please response ASAP.

Thank you all.

You are going to need an RS485 interface. There are several different ones, but they all do the same job. A module based around a MAX485 is quite popular and cheap. There are some versions that automatically switch from receive to transmit and back again but I've not used them, preferring to control the data direction myself.

Probably the main question is what speed do you need to communicate at? If it's 19200 or less, then you can probably get as a with any Arduino and use a software serial port to drive the RS485 interface. At faster speeds, you need to look for a board that has more than 1 hardware UART in order to achieve the speed needed.