Hi,
probing is a feature which in large measure is enacted by the motion controller and its plugin. I'm sorry but I don't think your controller
has the facility.
A G31 probe command operates something like this: Read G31 command G31 Z-1,for instance, Mach issues a move to the controller move to Z=-1 inch at
the current X Y co-ords, the controller issues pulses such that the Z axis drives downwards, the controller detects a probe strike and aborts the remainder
of the move, the controller reports back to Mach its current X Y and Z co-ords. The reported Z co-ord is the probe result.
If you used some other means the machine will try to complete the current move (Z goes down to -1) before it will detect or act on a probe strike signal and
drive the probe into the workpiece. Even if you could devise some way of having a probe strike signal issue a feedhold type command the latency of Mach
would cause the probe to continue downward sufficiently, to if not break it, certainly to far to be called accurate.
If you can't persuade the manufacturer of your board to invest in updating the plugin then buy another board from someone who has, there are some very
good suppliers who have sophisticated plugins and are almost continuously updated.
Craig