Hi Abel, unfortunately I don’t have any tutorial on that subject… I think this example might be useful for what you’re trying to do: https://arduino-info.wikispaces.com/SoftwareSerialRS485Example
I apologize for the late response. Regards,
I have the same issue. I have 35 srduino units displays, sensors, 8-channel light controlers) on an RS485 network. Can MQTT communicate with them?