Michael,

Try this site for a complete tutorial on stepper motors.


http://www.cs.uiowa.edu/~jones/step/index.html

Jones puts it all together in an easy to understand package...

Vern

michael brown wrote:
>
> Update
>
> It turns out that I *can* tie the center taps together.  Once I figured out
> the sequencing, I was able to get my driver board to make it go. ;-)  But
> I'm still confused as to what is the difference between a 2-phase and a
> 4-phase vs. uni-polar and bi-polar.  I think I understand the difference

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