A guy on the German vintage computer forum is restoring his Basis 108 to working condition, which prompted me to do some quick searches for that machine.

ROMs can be found online at the Internet Archive.

There are at least two different keyboard controllers, M5L8048 marked ASCII and DEUTSCH.

ASCII keyboard controller

German keyboard controller

As those are soldered in, motivating people to dump them will probably be hard ...

At least the post in the German forum contains a high quality scan of the Basis mainboard schematics.

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