you can do it via macropump macro.
you have to add some code in your digitze macro as well:
'put this as the first line in your digitize macro
SetOEMLED(1400,1) 'tell macropum it it a real digitze
'put this as the last line in your digitize macro
SetOEMLED(1400,0) 'tell macropum it it a real digitze is done
the the code for macropump
If ((GetOEMLED(1400) = False) and (GetOEMLed(825) = True)) Then
MSGBox ("Probe hit during cut")
DoOEMButton(1003) 'Stop machine
End If
something like this should work, code not tested, just written down