Today I got the encoder control inputs working, this means that all the controls, knob and usb interface work. I settled on having the voltage knobs default to .05V steps (1V/turn) with 1V steps when pushed in. The current knobs do .01A/step with 0.5A when pushed in. I might adjust those later, for now they seem like reasonable values. No converters assembled yet :/ I'm just saving the best part for last.

I resorted to ordering some 6N137 to isolate the serial link, they look fast enough to level shift the pwm, I shall see. 22 days for those to arrive, please stand by.

Switching to encoders means my knobs dont fit anymore, The ones I like are $3 ea online, so I'm tempted to make my own (hobbyist time is free) in the meantime I'll use whatever fits.