the great thing about this site is that sooner or later at least two people have a similar idea.... and contribute.
I've been playing with a pic based servo driver for a while. Microchip.com have Application notes on the subject. Still early days. Have a working board but no step direction input yet. Used 18245's so thats 3a 55v. I'll see if I can tidy it up a bit and put it here but It's not going to be of much use right now.
Went down a dead end trying to use a stepper motor as an encoder. Got a small stepper and a pic to produce encoder signals from a turning 1.8 degree stepper, but it only works reliably for fairly slow speeds. After that it's a dirty signal which looses position, which defeats the object somewhat. A hobby priced source of encoders would be nice.
One thing that was interesting while looking at J Kerr servo stuff and having the Microchip AN's with the sample circuits on the desk is that they're *very* similar. Maybe a product of the components but....
Rutex appear to use the Pic in thier product too in much the same way.  |