Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10 6/7/83; site hao.UUCP
Path: utzoo!linus!decvax!ittvax!dcdwest!sdcsvax!bmcg!cepu!hao!hull
From: hull@hao.UUCP
Newsgroups: net.micro
Subject: Re: anyone know about a single chip 1200 baud modem?
Message-ID: <1048@hao.UUCP>
Date: Mon, 9-Jul-84 19:19:13 EDT
Article-I.D.: hao.1048
Posted: Mon Jul  9 19:19:13 1984
Date-Received: Thu, 12-Jul-84 00:38:00 EDT
References: <1143@druxu.UUCP>
Organization: High Altitude Obs./NCAR, Boulder CO
Lines: 33

This taken from the Motorola Microprocessors Data Manual (DL-120)
MC6862  MOS (N-CHANNEL, SILICON GATE) 2400 bps MODULATOR
	2400 bps DIGITAL MODULATOR
The MC6882 is a MOS subsystem designed to be integrated into a wide range of
equipment utilizing serial data communication.  The modulator provides the
necessary modulation and control functions to implement a serial data communi-
cations link over a voice grade channel, utilizing differential phase shift
keying (DKSP) at bit rates of 1200 or 2400 bps.  Phase options are provided
for both the U.S. and international markets.  The MC6882 can be implemented
into a wide range of data handling systems, including stand-alone modems,
data storage devices, remote data communications terminals, and I/O inter-
faces for counters.  N-channel silicon-gate technology permits the MC6882 to
operate using a single voltage supply and be fully TTL compatible.  The modu-
lator is compatible with the M6800 microcomputer family, and provides medium-
speed data communications capability.

* Clear-to-Send Options
* 511-bit CCITT Test Pattern
* Terminal Interfaces are TTL compatible
* Compatible Functions for 201B/C Data Sets
* 1200/2400 bps Operation
* Answer-Back Tone

Comes in 24 Pin 0.6" width package.

But a single DIP does not a modem make.  The 1200 baud quad-phase di-bit
protocol used by modern modems requires fancy active filters for use on
telco's lines, what with the carbonated frogpond water they use to fill the
empty spaces.
							Howard Hull

{ucbvax!hplabs | allegra!nbires | decvax!stcvax | harpo!seismo | ihnp4!stcvax}
       		        !hao!hull