I am looking make my own version of theses digital relay/FET controllers so I can have more usability and matrixes.
it looks like to me they send a serial signal to the controller and then the controller turns the relays on and off. I believe I should be able to achieve the same thing with a arduino and a relay board. I thought about using resistors to sence voltage drop across the switches but then that would limit me to momentary switches only and no latching switches. Just need some help getting in the right direction. Does anyone know of a protocol or have a idea that would work good for this?