ajparent1/kb1gmx wrote:
A cpm based BBS was basically the CCP with undesired commands removed...
IT was also possible to time slice who was active... for more than one user
at a time (POTS ring down and multiple modems, so $$$).
MPM based BBS uses multiple Z80s each running an instance of CP/M+ (V3).
I once got a used S-100 computer (made by SD Sales around 1980) that worked like that. It ran MP/M, and had a 4 MHz Z80 as its "master" CPU, 256k of banked RAM, a Corvus hard drive, and an "I/O-8" card with eight Z80-SIO serial ports.
The computer was used for some kind of BBS-like setup for a company. It had 8 modems on the serial ports, so salesmen could dial in to check stock, place orders, etc. The I/O-8 card had its own Z80 and RAM, which created FIFOs for all the channels, which the main CPU would service.
It would have been interesting to see it work. But I only got the computer itself, without the modems or hard drive. I converted it to use floppies and ran regular CP/M on it.
The Walnut Creek CD has a few of the BBS system content and the system
software.
It would be straightforward to bring up a BBS on a Z80 like this with a standard phone modem. But that requires a "land line". I doubt that many people would want to call it -- especially since us vintage computer fans are spread so far and wide that it would be a long distance call.
Lee Hart
--
A designer knows he has achieved perfection not when there is
nothing left to add, but when there is nothing left to take away.
-- Antoine de Saint Exupery
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
Lee Hart