From owner-freebsd-hardware@FreeBSD.ORG  Tue Nov  6 13:04:15 2007
Return-Path: <owner-freebsd-hardware@FreeBSD.ORG>
Delivered-To: freebsd-hardware@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id DE47E16A420
	for <freebsd-hardware@freebsd.org>;
	Tue,  6 Nov 2007 13:04:15 +0000 (UTC)
	(envelope-from achill@matrix.gatewaynet.com)
Received: from smadev.internal.net (host3.dynacom.ondsl.gr [62.103.35.211])
	by mx1.freebsd.org (Postfix) with ESMTP id 4C62613C4B6
	for <freebsd-hardware@freebsd.org>;
	Tue,  6 Nov 2007 13:04:14 +0000 (UTC)
	(envelope-from achill@matrix.gatewaynet.com)
Received: from smadev.internal.net (localhost [127.0.0.1])
	by smadev.internal.net (8.13.6/8.13.6) with ESMTP id lA6D3tlZ028267
	for <freebsd-hardware@freebsd.org>; Tue, 6 Nov 2007 15:03:55 +0200 (EET)
	(envelope-from achill@matrix.gatewaynet.com)
Received: from localhost (localhost [[UNIX: localhost]])
	by smadev.internal.net (8.13.6/8.13.6/Submit) id lA6D3q9k028266
	for freebsd-hardware@freebsd.org; Tue, 6 Nov 2007 15:03:52 +0200 (EET)
	(envelope-from achill@matrix.gatewaynet.com)
From: Achilleas Mantzios <achill@matrix.gatewaynet.com>
Organization: Dynacom Tankers Mgmt
To: freebsd-hardware@freebsd.org
User-Agent: KMail/1.9.3
References: <200711021411.02488.achill@matrix.gatewaynet.com>
	<47305327.7050205@cam.ac.uk>
In-Reply-To: <47305327.7050205@cam.ac.uk>
MIME-Version: 1.0
Content-Disposition: inline
Date: Tue, 6 Nov 2007 16:03:52 +0300
Content-Type: text/plain;
  charset="iso-8859-7"
Content-Transfer-Encoding: quoted-printable
Message-Id: <200711061503.52706.achill@matrix.gatewaynet.com>
Subject: Re: Implementing a "normally open" relay
X-BeenThere: freebsd-hardware@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: General discussion of FreeBSD hardware <freebsd-hardware.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hardware>, 
	<mailto:freebsd-hardware-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hardware>
List-Post: <mailto:freebsd-hardware@freebsd.org>
List-Help: <mailto:freebsd-hardware-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hardware>, 
	<mailto:freebsd-hardware-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 06 Nov 2007 13:04:15 -0000

=D3=F4=E9=F2 =D4=F1=DF=F4=E7 06 =CD=EF=DD=EC=E2=F1=E9=EF=F2 2007 13:42, =E3=
=F1=DC=F8=E1=F4=E5:
> Achilleas Mantzios wrote:
> > Hi,
> > i am building a home security system based on zoneminder under FreeBSD
> > 6.2. I think i have it all sorted out, except a way to drive an external
> > alarm upon camera motion.
> >
> >
> >
> > Have two states:
> >
> > a) (normal) Have the two wires isolated from eachother, ground, voltage
> > b) (alarm) Connect the wires together (shortcircuiting the EOL).
> >
> > Could it be done someway with /dev/cuad* /dev/lpt*
>
> Probably overkill, but you can buy general purpose relay boards driven
> from the parallel port, e.g.,
>
> http://www.electronic-kits-and-projects.com/3074.htm

Thank you Chris,
thats probably a good solution for commercial/industrial applications.

Bill (WKK) gave me an excellent idea about using a modem, and it works
very good.

>
> Chris

=2D-=20
Achilleas Mantzios