About two years ago I found a schematic that showed how to wire an Arduino 4 channel relay shield with another 4 channel relay shield to allow the Arduino to control all 8 relays.
Does anyone know where I can find it? I have many Seeed 4 relay shields (v1.2) and I need to make a few 8 relay projects. I cannot find that info anywhere now. Any help would be greatly appreciated.
I am basically trying to find a wiring diagram that does this: