I found some technical documents for chips used in the systems:

NEC 7220D Graphics controller (Rainbow + DMV)

NEC D8741AD Peripheral Interface Controller (PC-D Graphics, DMV Mouse), has 1KB ROM area

SCN2674B Graphics Controller (PC-D Graphics)

Controller tech docs

Robert


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