I’d like to use TinyG for my Plasma table.
The torch could be started with the “Spindle” pin, but then a feedhold in the Gcode is needed until the “Arc OK” signal is present.
Could a home/limit input be used as a “feedhold resume”? I need only X and Y axis, the Z will be entirely controlled by the AVHC.
Is it worth waiting for TinyG to have such hardware input, or should I choose GRBL instead with it’s “Cycle Start” input?
It sounds like the plasma is similar to starting a spindle and waiting for it to spin up. A common way to do this is to issue dwell command (G4) for some number of seconds. Alternately, you can send the rest of the Gcode file after the arc is OK.
It would be pretty straightforward to connect the Z min and max pins to feedhold and cycle start functions, but this is not currently a function in the TinyG.