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Motion controller

Software vs. hardware motion controller

While a trapezoidal profile is easy to calculate, and a PC is usually adequate to drive the stepper signals, consider the following two drawbacks:

If you have an old PC doing nothing in a closet (like most of us do), don't mind have it dedicated for the CNC, have room for it, don't mind the jitter, etc... a PC as motion controller works fine.
But since here at fpga4fun, we like to listen to our MP3s and browse the web while processing our CNC jobs, all on our main machines, we built a simple hardware motion controller, based on an FPGA of course!

Hardware motion controller
An hardware motion controller has the following advantages:

A simple motion controller was built using a Saxo FPGA board, which has a USB-2 interface so is easy to interface to a PC.
The Saxo is placed between the PC and the Stepper controller.

A custom parallel adapter was made for Saxo.