> However, wasn't one of the early Santa Cruz Operation unices such
> that it could run on something other than a 286. But this is 
> so ancient
> I am very hazy on just what it was... 

That would be Microsoft Xenix, developed by SCO, and which was available on
The Zilog Z8000 as well as some either the 8086 or 80286.

BTW, the PDP-11/20 and PDP-11/40 didn't have memory mappers; that was an
option for the PDP-11/45.

Regards,
-Steve
--
Steve Byan <smb@world.std.com>