*BSD News Article 19478


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From: bde@kralizec.zeta.org.au (Bruce Evans)
Newsgroups: comp.os.386bsd.misc
Subject: Re: Using the sio ports for terminals w/o modem ctl signals
Date: 14 Aug 1993 05:59:38 +1000
Organization: Kralizec Dialup Unix Sydney: +61-2-837-1183 V.32bis
Lines: 32
Message-ID: <24grraINNl92@kralizec.zeta.org.au>
References: <1872@dcsc.dla.mil> <CBJnzu.6nG@obiwan.uucp> <1993Aug10.193616.16846@fcom.cc.utah.edu>
NNTP-Posting-Host: kralizec.zeta.org.au

In <1993Aug10.193616.16846@fcom.cc.utah.edu> terry@cs.weber.edu (A Wizard of Earth C) writes:

>In article <CBJnzu.6nG@obiwan.uucp> bob@obiwan.uucp (Bob Willcox) writes:
>>What about using sio on locally attached terminals connected through
>>a multi-port card (BocaBoard BB1008) that only has TX, RX, RTS &
>>CTS signal connections (via RJ-11 connectors)?
>[ ... ]

>Setting CLOCAL is *supposed* to work in this case.  Depending on which of
>the revisions of the serial drivers you are using, it will or it won't,
>with the highest probability on "won't".

Rubbish.  It will work for all drivers.

It works for the old com driver because that driver pretends that carrier
is always on, so the setting of CLOCAL is irrelevant.

It works for sio because I regard the CLOCAL on case as normal and made it
the default and tested it a lot.

There might still be problems from broken programs such as getty blindly
turning CLOCAL off.

>The correct way to handle this is to have a different driver for the board
>so that it ignores it before making requirements on the board at all; if the
>board provides these signals as "floating", it's a broken board.  From
>what I remember of the thing, it doesn't, and you *do* need a different
>(or at least indifferent 8-)) driver.

It is sufficient to have a non-broken board and/or cables with DCD wired on.
-- 
Bruce Evans  bde@kralizec.zeta.org.au