I think you can, depending if you want to run unipolar vs. bipolar mode.
All you would have to do is tie the middle of the coils to ground.... but bipolar mode is stronger, so I don't see the advantage of running unipolar.
In bipolar mode, you would likely just ignore the middle lead on the coils:
I have a version of PICStep with the board and schematic files included. It's in the thread called PICStep clone. I'll warn you that it may not be ready for prime time though. I haven't actually built and tested it yet (hopefully this week now that I have all the parts).Code:(------------ ( ( (------x ( ( (------------
I have seen a current chopping microstep unipolar circuit once. Check out http://pminmo.com/ .. has a some links about 6wire and 8 wire steppers.