Nice to learn about this multi-tasking operating system in those docs. Eventually I found the giveaway that it’s a Z80 system (which I surely could have found in other ways) which was a snippet about register usage. I suppose if the memory management uses an adder that might mean it’s a segmented system, rather than banked or paged??
Possibly we need a new topic explaining the history and family tree of these machines, but in the meantime, here are some previous threads:
Trying to find a Monroe computers list
Monroe OC-8820 repair project (part 1)
Back to Monroe OC8820 repairs
Also I found some DIAB related data at
https://dflund.se/~triad/diab/archive/
And a short discussion over here:
Litton - Monroe OC-8880 mini forum
Which linked to this site