The first reasonably stable AT&T unix for Intel I enountered was unix System V release III running on 80386 (32-bit) Intel processors. This was by no means the first AT&T unix or the best choice of processor. I much preferred Berkeley unix at the time.
In theory a 64-bit processor should be able to run 32-bit and 16-bit programs.
What usually stops you running old operating systems on modern hardware is the driver support, BIOS support, and address limitations. Don't expect a medium-age unix O/S to know about USB, SATA discs, or anything bigger than 2Gb.
You could perhaps try loading a modern Solaris (which has roots in AT&T and Berkeley) and then research what commands and features were available in early AT&T unix.
The excellent mascheck site will give you an idea of how much variation there has been.
traditional Bourne shell family / history and development
05-05-2012
) However I'm not sure about the legal issues and won't post links, so if you're still looking for something like that, PM me and we'll come up with something
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