Physicist trying to do engineering. Not going well. After advice with 4 axis gantry.

[JAZZCNC]

Hi Rob,

First don't get too hung up on the Bob cheap or Expensive they all do the same Job which is providing an easy way to connect to the Pulse device. They don't actually do much more than pass signals thru and thou not recommended you don't actually need one at all.
You could connect directly to the parallel port cable but it doesn't provide any isolation to the PC so not recommended as could damage the PC if anything goes wrong.

The Pulse device in your case would be the PC parallel port which needs Motion control software like Mach3/4 which provide Parallel port Driver which interfaces with the PC.

So put simply you need Motion control software like Mach3/4 or LinxCNC.
In your Case I suggest using LinxCNC as it's free and can be run directly from Boot CD ( I think.? I'm not into linx others will correct me if wrong).

To run Machine the process goes.

Control software >>>Pulse Device(parallelport)>>>BOB (optional) >>>Motor Drive>>>Motor.

Why can't you install Mach3.? is it because using 64Bit PC.?