If you can run a switch at each end (limit) of an axis and 1 in the middle (home), I believe during the homing sequence each axis hits their limit either + or - and then proceeds to look for the home switch and stops upon seeing/touching it. I believe this can all be acheived with 1 pin for all 3 axis'. Furthermore I would think I could run only 1 switch per axis in this case an optical switch. I would think placing a flag (a piece to interupt the beam) at each end of the axis and 1 in the middle for a home would be identical to the machine. I see people refer to needing a pin per axis for homing. That doesnt seem necessary. Possibly for 3-4 axis simultaneous homing. But will this work? If not why? Next I am going to be asking how I get an independent LED for each axis' switch, not just 1 for any switch triggered. BTW I run Mach 3.