Well, from what I can gather, I properly need to update speed/count/corrections every 1mS or so.
It seems that generally a PI function is used, instead of a PID, when it comes to motor control.
I'll spend some time trolling through PIC, Freescale, etc website looking for papers.
Some of the specific motor control chips may have some S/W that I can look at.
Thanks for the AccelStepper suggestion. Their site has some good stuff and the forum is usefull :-)
in case someone else is looking, here is the linkhttp://www.open.com.au/mikem/arduino/AccelStepper/