What pins do you have your stepper motor connected to? (thru the '2003 of course).
Also, have you been able to make your motor step using only push button switches...in other words, are you sure your motor will step as long as the software works properly (push one button, steps one coil, push another button, steps another coil, and so on)? I'd get that working first to make sure you don't burn anything up and worry about the software control later...
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