( Sorry about my absence from the list, lost my desktop computer and email, working from the archive and web based mail )

=======Begin Prior Post: =======
2007\01\25@093623 by Paul James E. 
  	
Russ,

Do you have the processor and any other IC's bypassed with a capacitor?
Also, do you have snubber diodes on the motor leads to clamp counter-emf
when the coil denergizes?  If not, these could possibly be causing a 
problem.  I built an application sometime ago that drove some stepper
motors, and what I done just because I thought it would be good practice
is to add a short delay (IIRC, about 50ms) after the processor
initialized, but before it started running the motor drive routines.  I
figured this would allow everything to settle out and stabilize before I
started the active part of the program.   You might want to try this to
see if it helps in your case.  In my case, it worked well.  I never did
take it out though to see if it still ran the same, but it did run well
with it in there.  My reasoning here is that when you first start up, and 
the outputs are configured, if even a lillet voltage is present on a
winding or windings during startup, when thing finally get switched off to
start the program at a known point, this counter emf may be causing noise
on the power supply lines or on the high impedance clock circuit, and
causing havoc.  I believe it's worth a try to either prove or disprove this
theory.  

Anyway, just a thought.  Let us know what you finally find the problem is.


                                              Regards,

                                                Jim

P.S.  How about posting a schematic and your code for us to peruse to see if
     we can see anything that way.  Strictly up to you though.

====== End Prior Post: Russ Says =====

Do have by passing, quite a bit, I may try still more.

Snubbers are built into the driver chip, but now I am not using the motors or the drivers and still cannot get the sucker to be stable.

I did not put a deliberate delay in but the blinking of the led's at the beginning of the program ( still in ) and earlier the user interface ( removed ) gave a substantial delay.

Schematic posted via link at:  http://home.comcast.net/~russ_hensel/Erratic/index.html



Thanks

	Russ
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