Good project Matt
(I’ve got a (39 year old) Quad FM4, but it’s staying as a tuner).
I’ve got a Digi HAT board using some of the GPIO pins, but only needed enough for 3 transport functions and a shutdown.
So I could use the ‘GPIO Buttons’ plugin to do this:
It depends what / how many functions you want to allocate to your remaining GPIO pins, as to whether you’ll be able to do all that you want with your FM4 buttons / LEDs.
Good luck - you can pretty much guarantee your finished product will be unique in the world.
