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From: SNELSON@STL-HOST1.ARPA
Newsgroups: comp.dcom.modems
Subject: Re: Hardware Protocol
Message-ID: <[STL-HOST1.ARPA]Tue,.25.Aug.87.07:48:06.CDT.SNELSON>
Date: Tue, 25-Aug-87 08:48:00 EDT
Article-I.D.: <[STL-HOST1.ARPA]Tue,.25.Aug.87.07:48:06.CDT.SNELSON>
Posted: Tue Aug 25 08:48:00 1987
Date-Received: Wed, 26-Aug-87 06:07:07 EDT
References: <305@pvab.UUCP>
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The ARPA Internet
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ROBERT:
RS449 IS THE STANDARD  YOU HAVE IN MIND. RS 422 IS AN ELECTRICAL
STANDARD FOR BALANCED DIFFERENTIAL DRIVERS TO WORK IN CONJUNCTION
WITH RS449, RS423 IS AN ELECTRICAL STANDARD FOR UNBALANCED DRIVERS
TO WORK WITH RS 449.

RS449 CONSISTS OF 2 CONNECTORS, 1 37 PIN AND 1 9 PIN. THE 9 PIN
CONNECTORS HAS YOUR SECONDARY SIGNALS ON IT.

2 SECONDARY RECEIVER READY
3 SECONDARY SEND DATA
4 SECONDARY RECEIVE DATA
5 SIGNAL GROUND
6 RECEIVE COMMON
7 SECONDARY REQUEST TO SEND
8 SECONDARY CLEAR TO SEND
9 SEND COMMON

IF YOU WANT I CAN SEND YOU A COMPARISON BETWEEN CCITT V.24 AND
THE EIA RS449 EQUIVALENCY ON THE 37 PIN CONNECTOR AND THE 9 PIN
CONNECTOR, IE., 102 SIGNAL GROUND IN V.24 EQUATES TO "SG" SIGNAL
GROUND FOR RS 449.

REGARDS

STEVE