After a few hours of work tonight, I managed to mate the NES controller with my mill. Seems to be a match made in heaven. The video is below for proof and the code is below that if you want to try this out for yourself (it's very easy).

I'm planning to make this a permanent feature of my mill. In order to give it a cleaner appearance (instead of just shoving wires into the controller), I've ordered a set of NES controller sockets from parallax which I will be mounting in my case.

A couple of notes:
1.) The code is terrible, I will try to clean it up and re-post sometime soon.
2.) This is a very easy project, If you're trying to interface your easydrivers with a 3 axis mill, a homemade bot, or anything else and want to add NES controller pad capabilities, give this a look. You'll be surprised.
3.)The X axis on my machine is terribly loud. I need to fix that it....
nes_stepper.pde
File Size: 5 kb
File Type: pde
Download File
02/24/2010 - EDIT: An updated version of the code used to drive 3 Easy Drivers via and Arduino and a classic NES controller. Not a whole lot of changes to the original, just a little bit cleaner, more concise, and thoroughly commented.
nes_stepper_cleanedup.pde
File Size: 4 kb
File Type: pde
Download File
 
 
The guys in the Sparkfun forum are really helping me get this thing going! Right now I'm working one axis at a time. Here is my attempt to move the Y-Axis with a 60oz/in stepper and the EasyDriver from Sparkfun.

If you have a listen, it starts out pretty well and then makes this terrible grinding/vibrating noise. I found out that is the motor stalling and/or loosing steps, It's could be from a variety of things, all of which sound pretty managable. I'll try to get it smoother and more consistent.

Although it's not perfect, I'm fully confident this solution is going to work.