EMC linux + CNC mill + CNC Lathe

[Leav]

Hello Netizens of ChiefDelphi,

Our team found a CNC mill and a CNC lathe in the back of the tech class store room.

Degem TP MI CNC mill
EMCO Unimat PC (not the "basic" model, the one under it)

Our problem, in both cases, is that we can not find the computer or the software supposed to run these machines,so I was thinking perhpas EMC might work, but I have never used it and have no idea what is needed to set it up.(the website is... not very coherent to me - to say the least).

So I have some questions which I am sure people here will be able to answer, since some of them are general questions about CNC:

1. How do stepper control boards(stepper drivers?) work? what is the input signal? (single pulse for each step on a control line?)
2. I know stepper motors are controlled by stepper drivers, but how are these drivers connected to the PC, and is there some sort of standard?
3. I gather that the PC connects to the boards through the serial port, is this correct?
4. How can I tell what the pinout should be on the serial port?

As you can see I don't think i'll have much of a problem setting up EMC, and I have a basic understanding of how the mill works, but I aam completely lost on how to bridge the two worlds, and non of the above have any information to help me out here.
Specifically it seems to me that I lack some basic knowledge about CNC setups that the EMC website assumes that I have.

Thanks very much for your help!
-Leav