I'm building a CNC machine to mill PCB's generated by Eagle produced GCode. The idea is to use a PIC4550 to drive 3 stepper motors and to accept instructions from the PC (using USB) to single step the motors, i.e. use the PC to generate single step commands from GCode produced by Eagle.
Any pointers or hints would be very welcome at this point, in particular, does anybody know whether this has been done already?