Spindle speed calibration

"You just need to wire A and I inputs together (with wires, at the board) and edit the HAL file to enable counter-mode:"
Since the index signal wire goes to physical pin 10 on the G540 can't I join the signals (encoder A and Z) in the hal file?

bill.anderson wrote: can't I join the signals (encoder A and Z) in the hal file?

No, partly because the index and A / B pins do not pass through HAL with a Mesa encoder counter, and partly because even if they did they would only be updated once per mS and that is too slow.