"That is "bi-directional", as in turning the motor both ways, vs only one
way
in the circuit above it. Have to keep your 'bi-'s straight, nothing to do
with
running a bipolar motor, that takes two full H-bridges as in his fig 6.1."
D'oh! I knew I should have gone to bed instead of kept on researching this.
"While 90% of the info on most of these basic stepper motor type web pages
is
correct, 90% or more of them also have a notable error or two."
And that's why I only 'add' to existing circuits. :) Putting in
opto-couplers and protection diodes does nothing to the overall performance
of a circuit. Either it worked to begin with, or it didn't.
I learned this real quick by reading a thread in Aaron's forum. Check it
out for yourself:
<
http://www.aaroncake.net/forum/topic.asp?TOPIC_ID=2996&FORUM_ID=18&CAT_ID=10&Forum_Title=Power+Supply&Topic_Title=12%2F120V+inverter+again>
I needed an inverter to power the backlight of a LCD and started reading
that to find a decent schematic. 13 pages later and I still don't have an
answer, the worst mumbojumbo I've ever read anywhere, it just goes on and
on...
And that's why I show you folks these circuits. I'd rather listen to your
opinion, than buying things that won't work with money I don't have.
Robert
:)
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