|
|
Message Digest
Volume 28 : Issue 258 : "text" Format
Messages in this Issue:
Re: Dr. James Marsters, TTY deaf service developer
Re: Dr. James Marsters, TTY deaf service developer
Serial communications (was: Dr. James Marsters, TTY deaf service developer)
====== 28 years of TELECOM Digest -- Founded August 21, 1981 ======
Telecom and VOIP (Voice over Internet Protocol) Digest for the
Internet. All contents here are copyrighted by Patrick Townson and
the individual writers/correspondents. Articles may be used in other
journals or newsgroups, provided the writer's name and the Digest are
included in the fair use quote. By using -any name or email address-
included herein for -any- reason other than responding to an article
herein, you agree to pay a hundred dollars to the recipients of the
email.
===========================
Addresses herein are not to be added to any mailing list, nor to be
sold or given away without explicit written consent. Chain letters,
viruses, porn, spam, and miscellaneous junk are definitely unwelcome.
We must fight spam for the same reason we fight crime: not because we
are naive enough to believe that we will ever stamp it out, but because
we do not want the kind of world that results when no one stands
against crime. Geoffrey Welsh
===========================
See the bottom of this issue for subscription and archive details
and the name of our lawyer, and other stuff of interest.
Date: Thu, 17 Sep 2009 11:29:19 -0500
From: Jim Haynes <jhaynes@cavern.uark.edu>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Dr. James Marsters, TTY deaf service developer
Message-ID: <slrnhb4out.3a6.jhaynes@localhost.localdomain>
In all this discussion of serial port connectors, we need to keep in
mind that RS-232 only specified the interface as a connector mounted
on the modem and a cord coming from the "business machine" to the
modem. If the manufacturer of the business machine decided to put a
connector there, as most of them did, then the pin arrangement was
not covered by the standard and could be anything at all.
I always like to save a portion of the blame for the standards process
in this country: paying for standards work by copyrighting and charging
for copies of the standard. The price is usually not high, but the
pre-Internet process of finding out who publishes the standard and how
to order copies was a significant deterrent. So many equipment designers
learned about the standard the same way they learned about sex, from
hearsay on the streets and playgrounds.
Contrast this with the way the Arpanet/Internet developed, with standards
freely available online.
Date: Fri, 18 Sep 2009 08:04:07 +1000
From: David Clayton <dcstar@myrealbox.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Re: Dr. James Marsters, TTY deaf service developer
Message-ID: <pan.2009.09.17.22.04.05.792237@myrealbox.com>
On Thu, 17 Sep 2009 14:03:28 -0400, Jim Haynes wrote:
........
> I always like to save a portion of the blame for the standards process in
> this country: paying for standards work by copyrighting and charging for
> copies of the standard. The price is usually not high, but the
> pre-Internet process of finding out who publishes the standard and how to
> order copies was a significant deterrent. So many equipment designers
> learned about the standard the same way they learned about sex, from
> hearsay on the streets and playgrounds.
>
> Contrast this with the way the Arpanet/Internet developed, with standards
> freely available online.
But it just highlights how various people will always disregard any
"standard" if it is convenient.
In the telecoms area I still recall various voice mail systems that used
DTMF in-band signalling who's designers decided that things like the
inter-digit pauses, minimum pulse widths etc could all be cut back from
whatever the standard was because it just worked with whatever other
equipment they were using at the time (why spend 3.3 seconds sending all
the tones when it can be done in 2.8 seconds...... our equipment is
"better" if it does this quicker.....)
The trouble was that later on someone would invariably try and get this
non-standard stuff working with something that was quite finicky with
anything outside the DTMF standard, and many (many) hours would be wasted
trying to work out what the problem was.
--
Regards, David.
David Clayton
Melbourne, Victoria, Australia.
Knowledge is a measure of how many answers you have, intelligence is a
measure of how many questions you have.
Date: Fri, 18 Sep 2009 04:29:03 +0000 (UTC)
From: "Adam H. Kerman" <ahk@chinet.com>
To: redacted@invalid.telecom.csail.mit.edu
Subject: Serial communications (was: Dr. James Marsters, TTY deaf service developer)
Message-ID: <h8v2af$g67$1@news.albasani.net>
Jim Haynes <jhaynes@cavern.uark.edu> wrote:
>In all this discussion of serial port connectors, we need to keep in
>mind that RS-232 only specified the interface as a connector mounted
>on the modem and a cord coming from the "business machine" to the
>modem. If the manufacturer of the business machine decided to put a
>connector there, as most of them did, then the pin arrangement was
>not covered by the standard and could be anything at all.
It didn't specify the well-known DB-25 connector, but gender of the
connectors was specified, male on terminal and female on communications
equipment. RS-232 standardized the voltage of signals and the functions
of the physical interface pins, up to 20 different signal connections.
I'm doing this from memory. I've got what's his name's famous book on
serial communications around here somewhere.
>I always like to save a portion of the blame for the standards process
>in this country: paying for standards work by copyrighting and charging
>for copies of the standard. The price is usually not high, but the
>pre-Internet process of finding out who publishes the standard and how
>to order copies was a significant deterrent. So many equipment designers
>learned about the standard the same way they learned about sex, from
>hearsay on the streets and playgrounds.
So a widely distributed method that educates the public on standards
could improve sex too? I'm willing to give it a try.
>Contrast this with the way the Arpanet/Internet developed, with standards
>freely available online.
One assumes memos were mailed back and forth in the beginning.
TELECOM Digest is an electronic journal devoted mostly to telecom-
munications topics. It is circulated anywhere there is email, in
addition to Usenet, where it appears as the moderated newsgroup
'comp.dcom.telecom'.
TELECOM Digest is a not-for-profit, mostly non-commercial educational
service offered to the Internet by Bill Horne. All the contents
of the Digest are compilation-copyrighted. You may reprint articles in
some other media on an occasional basis, but please attribute my work
and that of the original author.
The Telecom Digest is moderated by Bill Horne.
Contact information: Bill Horne
Telecom Digest
43 Deerfield Road
Sharon MA 02067-2301
781-784-7287
bill at horne dot net
Subscribe: telecom-request@telecom-digest.org?body=subscribe telecom
Unsubscribe: telecom-request@telecom-digest.org?body=unsubscribe telecom
This Digest is the oldest continuing e-journal about telecomm-
unications on the Internet, having been founded in August, 1981 and
published continuously since then. Our archives are available for
your review/research. We believe we are the oldest e-zine/mailing list
on the internet in any category!
URL information: http://telecom-digest.org
Copyright (C) 2009 TELECOM Digest. All rights reserved.
Our attorney is Bill Levant, of Blue Bell, PA.
---------------------------------------------------------------
Finally, the Digest is funded by gifts from generous readers such as
yourself who provide funding in amounts deemed appropriate. Your help
is important and appreciated. A suggested donation of fifty dollars
per year per reader is considered appropriate. See our address above.
Please make at least a single donation to cover the cost of processing
your name to the mailing list.
All opinions expressed herein are deemed to be those of the
author. Any organizations listed are for identification purposes only
and messages should not be considered any official expression by the
organization.
End of The Telecom digest (3 messages)
**********
|
or 