Parallel Port Programming

I don't know how many of you own Sega Saturns, but here's what I want to do. I have an Saturn Action Replay 4M Plus ( http://www.lik-sang.com/info.php?cat...ducts_id=1694& )and supposedly you can use a proprietary PC Comms card to backup your saves to your PC. Well, since I don't feel like buying the ISA PC card they sell and can't find it anyway I thought I'd try to write a program to try and do it. I found out what each pin on the card is for, but I don't really know where or how to start. I found the program they wrote using their comms card and after doing some research about the whole thing their program uses an environment variable called AR_PORT. Is there a way I could define such an environment variable on WinXP Pro called AR_PORT and have it point to the printer port? I may not have to write my own program then, just trick theirs. Any help/ideas would be appreciated.