Opto Isolation ??

Crew:

Life is good. I have two of three Camtronic 5A driver boards built and
seemingly
working. I also have a new PC running rtlinux and EMC. Did I say life is
good? :-)

Well, once I get some heat sinks installed on the driver boards I'll be
ready to
connect the expensive computer to the somewhat less expensive driver boards
and expensive stepper motors. I've been thinking it would be good to
opto-isolate
the computer from the drive circuits, either to be conservative or because I'm
paranoid. I think these circuits are very simple but I'm electronically
challenged.
I searched around the net and found some information but not quite the circuits
I need.

SO, I've made a shot at designing isolation circuits for the parallel port
Data Out
lines and Sense In lines for switches. I am hoping someone will look at these
and tell me if they will work or if not what modifications are needed. I think
these would be of use to many on the list and I'd be glad to write up the final
circuits for the list once they're working. Anyway, please take a look at
these
if you have the knowledge and a few minutes. Respond to me or to me through
the list. A temporary web page of these is located at:

internet.oit.edu/~currinh/opto.html

Any other tips regarding this computer/driver connection?? Is such
opto-isolation
a reasonable approach?

Thank you greatly for any help you can provide. It could same some magic
smoke. :-)

Hugh

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Hugh & Denise Currin
currin@...
Klamath Falls, Oregon USA
541/884-3023
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