[FluidNC Issue#1557] Feature: Support for spindels with dedicated start and stop signal

Machine Context

I use a Kavo spindle (Number 4442) with a Kavo HF Converter on my CNC. It works with a 10V speed control.

Feature Description

My spindle has no “combined” start/stop pin, it uses two separate input signal for start and stop.

To start the spindle I have to send a (at least) 100ms pulse on the start pin (pin 1).
To stop the spindle I have to send a (at least) 100ms pulse on the stop pin (pin 3).
The speed is configured via another pin, with the default 10V interface (pin 4).

What would be the preferred solution to control this spindle?

My idea was to add an additional disablepin for the 10v spindle, combined with an option to use a pulsecontrol mode, that uses pulses instead of a steady signal for turning the spindle on and off.

But maybe there are better options? Or even already existing options I haven’t found yet?

Other Approaches

The old controller I am trying to replace had the option to redefine the M3 etc. commands, so I could define some kind of macro for M3, I was fine with that solution, but it does not seem that fluidNC has a “stock”-way of redefining M-Codes?

How I Can Help

I am able to write the code needed for that feature myself, and I would even be fine to maintain my own fork, if this feature is not relevant for the community, but I am primarily interested in getting feedback about my idea and maybe some tipps how to get it done, as I am not that deep into fluidNC yet, it is my first my machine to be equipped with fluidNC.