Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!usc!elroy.jpl.nasa.gov!ucla-cs!uci-ics!zardoz!tgate!ka3ovk!drilex!axiom!linus!alliant!werme
From: werme@Alliant.COM (Ric Werme)
Newsgroups: comp.arch
Subject: Re: DECSYSTEM 20
Message-ID: <3302@alliant.Alliant.COM>
Date: 1 Aug 89 01:54:33 GMT
References: <11475@xenna.Encore.COM> <612@daitc.daitc.mil>
Reply-To: werme@alliant.Alliant.COM (Ric Werme)
Distribution: na
Organization: Alliant Computer Systems, Littleton, MA
Lines: 24

In article <612@daitc.daitc.mil> jkrueger@daitc.daitc.mil (Jonathan Krueger) writes:
>In article <11475@xenna.Encore.COM>, cook@pinocchio (Dale C. Cook) writes:
>>The 11 didn't really have a great deal to do while timesharing was
>>going on.

>I thought it handled terminal i/o, too, offloaded character
>interrupts, handled handshaking, may have done ^u and ^w.  No?

I forget what the Dec-20 did (it may have changed after I left, anyway), but
on TOPS-10 the console front-end did virtually nothing other than couple the
console frontend to the OS.  Other -11s attached to the DTE20 (DN87S) or
-11s attached to the DL10 (DN87) handled terminal concentrating and networking
tasks, including echoing.  The echoing was kinda nice - whenever the -11
handled a character it wasn't sure about echoing (generally control characters),
it would tell the -10 to start echoing and the -11 would take over echoing
after the line went idle or at some other convenient point.  I like it better
than the telnet echoing stuff, which I worked on at CMU.  As for offloading,
well, the network overhead was so high, it was more like onloading.

-- 

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