Hmm, encoding each adjustment into 3 bits just isn't going to do it justice anyway I try it. I lose either too much range or too much resolution in the saved values, which then makes saving them in the first place not very useful. The only way to really make 3 bits work is to do both - 1/2 the resolution and then limit the range, which is going to a pig to code.

I can save perfectly with 5 bits per slider - but that is a total of 20 bits (10 per power mode) which is probably too much flash usage.

Can we compromise on 4 bits per slider? (in which case I'll use spare8 instead of spare6.)