PMMI Bell 212A Modem
This was the next generation modem supplied by PMMI after their successful
The PMMI Bel 212A was IEEE-696 compatible. It had auto answer and auto dial
capability and ran at two different rates. 45.5-300 baud and at 1200 baud.
It had full and half duplex capability. As with the MM-103 it utilized
four consecutive IO ports on the bus. It could also be setup to
utilize the interrupt lines .
As for other PNMI and Hayes boards, while some simple software was provided
with the board. The vast majority utilized public domain CP/M programs like
Modem 5 or 7 with this board.
I do not yet have a manual for this board. If you have one please let
The PMMI brochure can be obtained
Note on Bell 212 A Protocol
Synchronous/ asynchronous data transmission,
full-duplex operation over 2-wire leased or dialup lines; 1200-bps data
rate. This versatile standard provides for efficient full-duplex operation
over 2-wire dialup lines. If you add a leased line, however, you can still
use Bell 212A. Comparable to ITU V.22
This page was last modified