I never really figured I'd find a use for 'hfModulation' for motors, as generally PWM works well, and generally you want to minimize the number of level-transitions so the MOSFETs don't sit in the resistor/heat-producing state for too long/often... But I finally found a purpose for using it with motors, and there's a bunch of other info here about hfM and power-supplies. (TODO: put a bunch of this info as comments in the code!) And another blog-mention. Too Cool!

Oh, also, I think we determined with some amount of certainty that 'hfModulation' is actually "first-order delta-sigma modulation".

And, if you don't know, 'hfModulation' is used for several purposes including LED fading in 'heartbeat', pixel-stretching in 'lcdStuff', bit-stretching in 'polled_uar' and 'polled_uat', is used to increase the resolution on my 'racer' game's track, and several other things. It works well for purposes where division would otherwise be used within iterative loops.