Yes that is not very hard. A simple O-sub can handle it. Then if you want to trigger it from a button (vcp or real) that isn't hard either.
Is your pad position is in the machine absolute position (G53 X0 Y0) and do you want to use tool offsets or just machine coordinates for setting your Z?
Here is a sub I use to probe the material surface height on a cnc router. It just uses a metal pad laid on the surface and a wire clipped to the tool and sets the ZG54 offset
Code:
o<probe-z> sub
M66 E0 L0 (reads probe thickness setting from a user input)
#1=#5399 (0.02" probe thickness)
F10 (probe feed rate)
G38.2Z-1.0 (probe command)
G53 G0Z 0.0
#2=#5063 (Z probe result coordinate)
(debug, #5223) (old G54 Z offset)
#3=[#2-#1]
(debug, #3)
#4=[#5223+#3]
(debug, #4)
G10 L2 P1 Z[#4] (Change G54 Z offset)
o<probe-z> endsub
%
The code would be similar for setting a tool length offset. You'd probably want to add a G53X0Y0 to move to your probe position, and it would use G10 L10 P#5400 instead of G10 L2 P1. Some of the other variables may need changed as well.
