forum.cncdrive.com

I have 2 NC probes. Probe 1 goes to Pin 12 / Port 2 and Probe 2 goes to Pin 10 / Port 2. Both are check marked ACTIVE LOW and are run on 5 volts + through the probe and back to the inputs.

Probe 1 is in a fixed position for measuring tools taken from my Automatic Tool Changer (ATC).
Probe 2 is portable and plugs in for setting the material top surface height.

Both work as they should with one hiccup that is not critical but which I don't understand.

Since Probe 2 is portable I unplug it when not in use. What I've found is that when it is unplugged my M931 macro for Probe 1 measuring after tool pickup generates a device is active error message. If I plug Probe 2 back in then everything works as it should. I have a jumper jack I'm plugging into the portable Probe 2 outlet that overcomes the problem. It completes the 5v+ circuit back to Pin 10 / Port 2 the same way the NC probe would.

But why would Probe 1 care if Probe 2 is not sending back the NC 5v+ signal to Pin 10 / Port 2 ? Everything else on the CNC seems to work just fine without the jumper jack in place. Would the problem be resolved if I took Probe 2 to a different input port.......say Port 1 which is also 5v ? Or is UCCNC simply seeing an open circuit and giving the error message. Changing the ACTIVE LOW check mark on either or both probes makes no difference.

Thanks,
BH

there are 2 probe inputs so you can mix and match probes. nc / no
both give just a probe signal input. which is what the control sees.

both will be seen as the same thing.
probe routines are only looking for an input mapped as probe.

I'm guessing if you look at the diagnostic page, that the probe LED will light up when you unplug the probe, meaning the input is being triggered with the probe unplugged, due to the way the pin needs to be configured for your probe.
If so, the simple answer is to leave the probe plugged in.
Otherwise, create a duplicate profile with the second probe disabled, and use that profile when the probe is unplugged.