GFS,
We looked at MP/M for the office with a nice looking big machine which had S-100 cards. I think it ran on a Z-80. In the infinite wisdom of the boss, it was decided that we only needed one computer which turned out to be a Zenith Z-100 with two 8 inch floppy drives from Priority One. We ran it on CP/M, I had RCP/M set up on it so I could run it from home via the hayes, telco and my Osborne with its hayes (1200 bps - gasp). I was in Chicago at the time which was very active in hobbiest computing. I can can still remember being astonished at how may people could write assembler for USARTs off the top of their heads.
it'll take me a couple of weeks to get on top of this, assuming, as I do, that it is possible.
thanks for your interest.
john