1986 BMW 325 Anti-theft code problem

I just bought this vehicle from a friend and drove it home, not aware it had an anti theft device as part of the on board computer, I pushed the code button. And someother stuff. And now it wont start. I accidently engaged the anti theft mechanism and no one knows the code or what to do.I am completely lost and can't drive my new/old car because of this. Any ideas on how to reset it? Is there any thing I can do other than towing it to a repair shop? Thank You