Hacking a Roland CAMM3 PNC-3000

[Robin Hewitt]

It's been driving me spotty, but I think I am now convinced that it's the X,Y,Z position display that is wrong not the steppers. Time to give up on the displays and do some CNC type moving.

With my harum-scarum step sequence the counter stays 100% in synch with the steppers.

With my everyone moves together routine the displays are out one count per shift.

Makes not a lick of sense to me.

Pic is the encoder output. When you turn the dial one click you get a 1.25mS pulse. If direction changes you see the direction line (yellow) go 1.25mS before the pulse. This is surprisingly convenient when you are sampling at 1KHz to get 5mm/s at 200steps/mm. The motor will happily slam in to reverse at 5mm/s. Another clue that their 500Hz double step was a ghastly bodge to overcome a problem with the display :naughty: