PLC M12 is a Base specifically design for industrial application. DC Power in 9-24V. Does this PLC remind you of the 'PLC' in industrial controll short for 'Programmable Logic Controller'. This PLC base is not the typical 'PLC' used in programmable controller, but its does able to implement the most common controller in industrial field. Based on the current M5 development system, you can add as many Realys as you want, you can enable the TTL-RS485 communication, you can layout your customized circult on the protoboard. you also can make it an LoRa node by stacking a LoRa module etc. This base gives you an unlimited number of combinations, it is powerful, flexible, and covered with an industrial-grade case. If you happen to work in an industrial field, We especially recommend this PLC base to you which will surely give you the best and the fastest way to resolve your requirement.
If you need to add RS485 interface, soldering the RS485 board onto the mian board pin correspondingly. The serial port pins on the RS485 board will be connected to the GPIO16 and GPIO17 of the PLC backplane.