Ok, you can connect that to motion.digital-in and use that to wait for the arc before proceeding with the cut.
net start-motion motion.digital-in-00 <= parport.0.pin-15-in
Of course using what ever in pin you choose.
And in your code after issuing a M3 you do a M66 as shown in the sub below. The following subroutine is what I call after moving to the start position for the cut. It finds the material top, moves to pierce height, starts the torch, waits for Arc Ok then moves to cut height
o<touchoff> sub
(#1 pierce height, #2 pierce delay, #3 cut height)
F10
G38.2 Z-1.75 (Probe to find the surface)
G91
G1 Z0.070 (Raise up to Z0)
G90
G92 Z0 (Set Z0)
G1 Z#1
M3 S1
M66 P0 L1 Q5 (Wait for Arc OK from Torch)
G4 P#2 (Pause for pierce delay)
F25
Z#3 (goto cut height)
o<touchoff> endsub
M2
This is an example of how I call the touchoff subroutine.
(move to start postion)
o<touchoff> call [0.125][0][0.080]
Fn (set cutting speed)
...( cut profile)
M5 (turn off torch)
G92.1 (clear my G92 offset)
G0 Z0 (move the torch up to clearance height)
M2
As for Torch Height Control (THC) I cut for a year without one just by careful placement of my material on the slats and making sure it is flat.
John
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