Reverse engineering circuitry in a Spacelab computer from 1980
26 points by elpocko 2 hours ago | 3 comments
kens 2 hours ago
Author here if anyone has questions...
replymonocasa 42 minutes ago
When you say that the 125 added memory management, what does that mean a little more specifically? My guess is either PDP-11/z280 style paging without page tables (the 16 bit address space makes just having enough IO registers to cover the address space tractable) or some simple segmentation hardware, but it'd be neat if there was another hardware object capability system I didn't know about.
reply
I don't have the patience to reverse-engineer these types of boards, but I do find them really interesting to think about. CAD was just getting started (I just looked up that Gerber format was released in 1980) so I wonder if the masks were hand-drawn.