Lower the tick rate from 10kHz to 1kHz (otherwise all the extra interrupts reduce the achievable scan rate). Enable the WAIT_US_TIMER using GPT TIM3. Observed scan rate on the K320 is increased from 625Hz to 2090-2120Hz.
Co-authored-by: Tyler Tidman <tyler.tidman@draak.ca> Co-authored-by: Simon Arlott <sa.me.uk>