Tom

Thank you, I was fishing for a way to move the KSTEP input functions to another KFLOP port(s) (J4 and or J6) so I could use the predefined serial routines on J 7 to query an external isolated ADC.

I understand conceptually the dual loop approach you are speaking about for THC. I am a bit lost on how you define it in Kmotion. I know that I can make a micro read an ADC and output a quadrature pulse train that follows a change in input voltage so one of the encoder inputs can be used. This has the problem is that I need to control the arc voltage to about +/- .2VDC or better to get good height accuracy over a full range of arc voltages ( 0 to 200VDC for cutting and up to about 325VDC open circuit). Now I know with some clever design I could get it so I only need to send data for the 50VDC to about 200VDC range. What I am not sure about is a clean way changing filter response and initializing the starting voltage in both the micro and KFLOP. I was really hoping to avoid the multiple communication paths that the better THCs use to pass data between the parts. Another minor detail is freezing the torch at a preset height when the feedrate slows for corners and smaller arc segments, most THCs use special M codes inserted by the PP. Also the THC needs to be aware of the state of the torch function. This was why I originally wanted try and do everything in the KFLOP.

John