Yes, I have tried Active high as well. I am suspecting that iether I need to upgrade to the latest version of Mach3 or else I will have to use to original input pins 10, 11, 12, 13 and 15 (as it states at the bottom of the window in the "Input Signals"). The problem is that pin 10 & 11 are occupied by the fine positioning encoder and pin 12 is occupied by the probe. Now I will try to use pin 13 for the Start and 15 for the Stop commands but would still fall 1 switch short for the Z axis auto zero command. On the otherhand .... now that I'm thinking of other possibilities ..... maybe another alternative is reroute/declare other pins (eg pin 2 & 3 of port 2) in the Encoder/MPG's window for the fine positioning encoder ..... I think this should work!!! I'll keep you posted.
In the mean time, any remarks or ideas are always welcome.
Thanks
Marting