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From: Michael Smith <msmith@atrad.adelaide.edu.au>
Message-Id: <199612060524.PAA26375@genesis.atrad.adelaide.edu.au>
Subject: Re: Help! Turning off DTR on a serial device
In-Reply-To: <199612060459.PAA10852@godzilla.zeta.org.au> from Bruce Evans at "Dec 6, 96 03:59:18 pm"
To: bde@zeta.org.au (Bruce Evans)
Date: Fri, 6 Dec 1996 15:54:07 +1030 (CST)
Cc: brandon@glacier.cold.org, mtaylor@cybernet.com, hackers@freebsd.org
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Bruce Evans stands accused of saying:
>
> This is why DTR should be controlled using tcsettattr() instead of the old
> ioctls. Set the output speed to B0 to turn DTR off. Keep it as B0 to keep
> DTR off. Set it back to the actual speed to turn DTR on.
You're not keeping enough state on the problem here folks. The original
poster is trying to talk to a VISA FEP which is a braindead piece of
crap. One of the contributing factors here is that it wants to be
talked to with DTR _NOT_ asserted.
Unless my understanding of comparam() is wrong, setting a speed of 0
will program a divisor of 0 as well, which is not helpful.
> Bruce
--
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