I was sent pictures of a PC-X mainboard and auxiliary boards.

https://dl.dropboxusercontent.com/u/55419307/Siemens%20PC-D/PC-X%20MR.rar

Maybe the MMU can be identified.


NCR DMV- DEC Rainbow- Siemens PCD- ITT 3030-Oly People- Acorn A5000- Olivetti M20