From owner-freebsd-questions Tue Feb 17 08:16:48 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id IAA19558 for freebsd-questions-outgoing; Tue, 17 Feb 1998 08:16:48 -0800 (PST) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from cerberus.partsnow.com (gatekeeper.partsnow.com [207.155.26.98]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id IAA19545 for ; Tue, 17 Feb 1998 08:16:40 -0800 (PST) (envelope-from don@partsnow.com) Received: (from bin@localhost) by cerberus.partsnow.com (8.8.5/8.6.9) id IAA18454; Tue, 17 Feb 1998 08:17:21 -0800 (PST) X-Authentication-Warning: cerberus.partsnow.com: bin set sender to using -f Received: from wildeweb(192.168.100.10) by cerberus.partsnow.com via smap (V2.0) id xma018444; Tue, 17 Feb 98 08:17:15 -0800 Message-ID: <34E9B796.DC9E5BEA@partsnow.com> Date: Tue, 17 Feb 1998 08:15:18 -0800 From: Don Wilde Reply-To: don@partsnow.com Organization: Soligen, Incorporated X-Mailer: Mozilla 4.04 [en] (X11; I; FreeBSD 2.2.5-RELEASE i386) MIME-Version: 1.0 To: "Alex N. Zhuravlev" CC: questions@FreeBSD.ORG Subject: Re: I need a device which can signalize the connection lost References: <199802170609.NAA27582@keep.scn.ru> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > You see ... It must be a remote device.And a person who can only understand that if > the light is on all OK and if off then he must call administrator. That's all. > I saw a neat tip in Electronic Design a while ago. You have a free serial port on your machine? After your ping script reports failure, have it toggle one of the free bits in the serial port, like DTR or CTS. On the other end of that bit, have a red-green (or red-white) bi-color LED plus a resistor tied to ground. You'll have to experiment, because line loss in the cable to your 'remote device' will reduce the voltage, but all you need is the LED, two wires and a resistor. In a nutshell, toggling a serial bit causes the output pin to toggle between + and - 12 volts DC with respect to pin 7 common ground. You could even just use TX and send data out the port at a low baud rate. This will give you red-green flashing. You know, this really is almost just $0.02 worth :) -- oooOOO O O O o * * * * * * o ___ _________ _________ ________ _________ _________ ___==_ V_=_=_DW ===--- Don Wilde [don@PartsNow.com] [http://www.PartsNow.com ] /oo0000oo-oo--oo-ooo---ooo-ooo---ooo-ooo--ooo-ooo---ooo-ooo---ooo-oo--oo  To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message