Need Help!- Configuring 'Probe' and 'Home'

[jong664]

Am new to this subject. Presently in the middle of converting and old Nu-Tool Mill (similar Sealey SM25).
Will be using Mach3 and 2x parallel (LPT) ports for connections.
Plan to have only 'home' switches (XYZ) linked to one input port and make use of Mach's inteligent management (one axis homeing at a time.
Am also panning to integrate MPG (ISM1468 obtained fromZapp)

Problem - Am running-out of available input ports !!

Do you think it would be possible to use the 'home' input for a 'probe' input as well ??

Thinking of wiring 'home' switches in parallel with one end on 5V pull-up and other end to ground.
This way, any 'home' switch being 'made', or the 'probe' grounded during "Auto Tool Zero" will trigger (inverted) the same input pin.

Would obviously work for 'axis-home' if 'probe' was isolated - BUT would Mach3 complain if during "Auto Tool Zero" an axis-home signal was discovered??

Any comments/guidence appreciated

Rgds.

Jon. GEORGE

[ger21]

BUT would Mach3 complain if during "Auto Tool Zero" an axis-home signal was discovered??

Mach3 would think the probe was triggered.

As long as no home switches are triggered while probing, and no probe is tripped while homing, it should work fine.