Quote Originally Posted by dazp1976 View Post
Diagram looks like some kind of 4 pole contactor type where the coil activates all the contacts at once.
Positioned all 4 NO for UC300 use and NC for arduino.

I'd suggest the most used one of the 2 controls be on the NO side then power the switch to the coil to flip it NC for the other.

Step/Dir could be a problem if the logic I/O flips with contactor switch over could it not?.
I don't know what would be the point of changing to your suggestion. The way I do it works fine. The switch is manual, has actually nothing to do with Arduino. Step/dir/en is controlled by Arduino or UCCNC, depending on the position of the switch. Why would Step/Dir be a problem...? As I said, it works and I use it.