No updates for a while, but stuff has been happening:
I've been working on interfacing the RC receiver to the Maple Mini via 6 pins. I'm going to be using interrupts triggered by timer input captures, but initially I'll be using external interrupts. I've had pointed out this morning that I can have a single pin for all 6 channels by doing a logical OR. This means that I free up 5 pins and also 3 PWM channels, allowing all of the measurements to be done with a single PWM channel or external interrupt.