Struggling with Steppers
February 22, 2012
I'm interested to experiment with Steppers - I have scrounged a few 5 wire unipolar (i think) steppers and figure I'd try and use my trusty STAMP to make them run :
I've never run steppers before bu thave been reading a bit. Key point I don't want to spend a fortune on some driver board, but to lash up something myself (which is always more satisfying)
I figured on using something like a ULN2003 to supply a suitable voltage based on control signals from my stamp. I figure I can then pulse out ABCD, ABCD etc or DCBA, DCBA to go the other way and then have the amplified voltage supplied to the correct lead. the faster I poll the STAMPS, the faster it runs - simple?? (too simple????)
Now here's where I need a bit (a lot) of help - is there some way to sense which of the wires I should pulse next, as I don't actually know what the resting position of my rotor is in .
OR can i just send my preferred sequence and the stepper will kick in when it gets in phase ? obviously I've not tried anything yet, but would really value some advice/ sample circuits etc. that might help me here