On Tue, Jun 21, 2011 at 9:24 AM, RussellMc wrote: > Providing actual circuit diagram and pointer to data sheet of actual > motor used would be wise. > Pointers to daya sheets of ICs used would be a bonus. > Then anyone deciding to wade in does not have to search for material > that you have already got available. > Excellent points, which I should have thought about before asking for help. Schematic is here: http://s1218.photobucket.com/albums/dd411/picster733/?action=3Dview¤t= =3Dsteppercontrolcircuit.jpg Datasheets: -LMD18245: http://www.national.com/ds/LM/LMD18245.pdf -MAX5820: http://datasheets.maxim-ic.com/en/ds/MAX5820.pdf -PIC18F2410: http://ww1.microchip.com/downloads/en/DeviceDoc/39636d.pdf -Anaheim Automation 23Y-104S-LW8 motor: http://www.anaheimautomation.com/manuals/stepper/L010164%20-%2023Y%20Series= %20Spec%20Sheet.pdf > > I assume / hope that your recirculation circuit is not trying to clamp > a winding that is effectively transformer coupled via the stepper core > to a driven winding. I've seen it done. I hadn't thought about this before, and maybe I'm misinterpreting what you're saying, but wouldn't there always be magnetic coupling between the 2 sets of windings? Thanks, Jim --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .