Controlling a stepper motor/motors (21-02485-03 and a 28YBJ-48) with a 08M or 20M2 Picaxe


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Attached is a PDF of several schematic showing the wiring to connect the steppers and also the programs:
One 21-02485-03 stepper being directly controlled/driven by an 08M Picaxe.
One 28YBJ-48 geared stepper motor being controlled by a 08M Picaxe and driven via one ULN2003 chip.
Two 28YBJ-48 geared stepper motors being controlled by a 20M2 Picaxe and driven, each by it's own ULN2003 chip. Controlled one at a time.

These programs do not use the binary control method to control the stepper coils, but use the high/low method. I'm sure there are better ways of doing the over all program, but at least the PDF might come in handy for reference.

The 20M2 controlling the two steppers has inputs for:
stepper selection one/two
clock-wise/counter clock-wise direction
single/continuous The 20M2 can run one sequence continuously, will run one sequence one time or will run one sequence a preset number of times (revolutions).
full/half step mode
auto/man mode
start push-button
the distance (sequences) is set via a 10k potentiometer.
the speed (pause between steps) is controlled by another 10k potentiometer.
Changing the auto/man or single/continuous switch's position, while running, will stop the stepper, after it finishes a sequence.