From: "Ian W. Wright" <Ian@...>
Subject: Re: Stepper controllers
Thanks very much Paul, this is helpful. I did try using opto isolators
on one of my early experimental circuits but they just seemed to gum
things up, however, I think now that the problem might have been a
current limitation on the parallel port - I hadn't thought of that. I
have been surprised that I can't drive the steppers reliably with the
486 computer and that stepster and MaxNC both seem to need a pentium as
I too can remember 8080s doing the job admirably in industrial
environments. In fac, only last year I was playing with a giant Asquith
miller (12ft x 8ft bed!) at a military aircraft factory which still uses
an early computer fed by 8" floppy disks.
Ian
[How fast are you trying to run your steppers? I've run MaxNC's software
successfully on one of their machines, using an antique 386, and it worked
fine- no lost steps. Perhaps if you get into higher speed ranges you need a
faster CPU. But there might be a problem coordinating the speed of the
motors with the speed of the computer. MaxNC has a program called "Timeset"
that you need to run when initializing a machine- did you do this?]
Andrew Werby
Andrew Werby - United Artworks
Sculpture, Jewelry, and Other Art Stuff