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From: henry@utzoo.UUCP (Henry Spencer)
Newsgroups: net.dcom,net.periphs,net.news
Subject: 9600 full-duplex, by trickery?
Message-ID: <4468@utzoo.UUCP>
Date: Mon, 15-Oct-84 17:44:35 EDT
Article-I.D.: utzoo.4468
Posted: Mon Oct 15 17:44:35 1984
Date-Received: Mon, 15-Oct-84 17:44:35 EDT
Organization: U of Toronto Zoology
Lines: 22

A recent issue of Electronics Week has a very interesting ad on the back
cover.  It's from Universal Data Systems (Motorola's modem subsidiary),
and what it plugs is a UDS 9600 A/B -- a fairly ordinary 9600-baud half-
duplex modem -- plus an "EC100" box which does error correction *and*
makes the half-duplex modem look full-duplex!

Does anybody know how well this thing works?  I assume that the EC100,
error-correction functions aside, is basically just some buffering and
an intelligent line-turnaround algorithm.  If one assumes that total
average traffic, both directions together, is somewhat under 960 cps,
then making a half-duplex channel look full-duplex is indeed feasible.
They're pushing it for terminals, where the assumption is plausible,
but it might work well enough for things like uucp.

They say "for details, phone (800)633-2252 x356".  Unfortunately, when
I try this I get an error message from the phone company.  (Probably
because there's this international border in between...)

Anyone ever heard of this widget, or worked with one?
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry