Chuck,
- You worry too much.
The Gcode interpreters do it all for you. They all have the ability to run all the popular setups. Here is what you need:
- Machine control software (gcode interpreter) such as TurboCNC, CNCpro, Mach 1 etc.
A bit of hardware called a driver or controller card. Stepperworld, Gecko, Xylotex etc. It interfaces with your parallel port, and wires go to your motors
- Motors (steppers)
The above mentioned software can easilly be configured for whatever you build, no matter what you use. You set it up for pulses per inch of travel, so it doesn't matter if you use 200 or 400 step per revolution motors, or if you use 3,5,8,10,20 or whatever pitch screws.