If you want an open source PID servo controller, which is also available as a very low cost kit, this one is released, tested, and works:
BOBPID1: PID Servo Controller massmind
If you want an open source PID servo controller, which is also available as a very low cost kit, this one is released, tested, and works:
BOBPID1: PID Servo Controller massmind
James hosts the single best wiki page about steppers for CNC hobbyists on the net:
http://www.piclist.com/techref/io/steppers.htm Disagree? Tell him what's missing! ,o)