Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!uw-beaver!rice!sun-spots-request
From: tpc@bnr-fos.uucp (Tom Chmara)
Newsgroups: comp.sys.sun
Subject: Re: Sun serial port communication problem
Message-ID: <292@bnr-fos.UUCP>
Date: 3 Mar 89 22:22:26 GMT
References: <13782@bellcore.bellcore.com>
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Organization: Bell-Northern Research, Ottawa, Canada
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Approved: Sun-Spots@rice.edu
Original-Date: 20 Feb 89 17:13:23 GMT
X-Sun-Spots-Digest: Volume 7, Issue 179, message 5 of 11
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quasar@ctt.bellcore.com (Laurence R. Brothers) writes:
>My test reader just does an open on /dev/ttyb and sits there busy-waiting,
>copying anything it reads to stdout. To write to ttya, I just either cat a
>file into the device, or open it for writing from a toy program.
>
>The problem is that my reader reads garbage....

Sounds like a problem I had at one point.  The problem turned out to be
that I hadn't turned off echo on the ports; each character was echoed by
the terminal driver, and was then looped back into the driver, which took
it as more input... (on top, of course, of the input I was already
squirting into the port, and output from any shell or application with
which I was communicating).  And you're right --- the garbage looks
"familiar", because what you'd really expected to say (and any output from
your input) IS in the text; it's just buried in gibberish...

Sorry about the delay in getting this out (and that it's a posted
message); our mail feed has been refusing to talk with us lately, and
though I think I have it working, I'm trying this means just in case...

	---tpc---

Tom Chmara			UUCP:  ..utgpu!bnr-vpa!bnr-fos!tpc
BNR Ltd.  			BITNET: TPC@BNR.CA