IIRC you go to
http://www,vt100.net/rm/ and follow the
obvious link for
documentation. Near (at?) the top of the list is a
source listing for
an
early version of the COS monitor. It's about half a
megabyte, pdf.
A quick trip to the attic restored my faith in my sanity (not a good
measure of anything, but it's all I have to go on :-)).
I found "Resaerch Machines COS 4.0 Assembly Listing" for Release 4.0B
from October 1981.
The reason I've not scanned it is that it is a perfect bound book (I
think that's the term, pages glued into the spine). So I can and will
scan it, but it will take a little time since I cannot spend hours
at the office scanner :-)
There are other similarly unscanned RML manuals up there, so I'll
make a proper list at the weekend.
Antonio