D.C. Hayes -- Micromodem 100
This was Hayes second S-100 modem board. It ran at
speeds from 45 up to 300 Baud.
The MICROMODEM 100 was a complete data communications system for S-100
microcomputers combining on a single board functions which formerly required
a modem, an automatic calling unit and serial and parallel interfaces. The
result was a sophisticated computer-to-computer or terminal-to-computer
modem for use in small computer systems.
The MICROMODEM 100 provided all the capabilities of a serial interface card
and an acoustic coupler, with the addition of programmable automatic dialing
The MICROMODEM 100 came with its own MICRO-COUPLER™ unit. This was at the
time an exclusive new device that allowed you to connect your S-100 computer
directly into any modular jack provided by your local telephone company
without the need of a DAA from the Bel system as was the case with the
The board had the following features:-
The brochure for this board may be
Fully S-100 bus compatible including
16-bit machines and 4 MHz processors.
Two software selectable baud rates —
300 baud and a jumper selectable speed from 45 to 300 baud. (110 was
Supported originate and answer
Direct-connect Microcoupler. This
FCC-registered device provided direct access into the local telephone
system, with none of the tosses or distortions associated with acoustic
couplers and without a telephone company supplied data access arrangement
MICROMODEM 100 could automatically answer the phone and receive input; it
could also dial a number automatically.
Software compatible with the D.C.
Hayes Associates 80-103A Data
Over the "modem years" the Hayes modem command set enlarged and evolved. It was
incorporated into modem LSI chips like those of Rockwell and was essentially the
standard for any computer controlling its modem interface.
A listing of this "AT" command set can be obtained
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