From owner-freebsd-questions Fri Jul 7 10:58:57 1995 Return-Path: questions-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id KAA19240 for questions-outgoing; Fri, 7 Jul 1995 10:58:57 -0700 Received: from lupine.nsi.nasa.gov (lupine.nsi.nasa.gov [198.116.2.100]) by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id KAA19234 for ; Fri, 7 Jul 1995 10:58:55 -0700 Received: (from mnewell@localhost) by lupine.nsi.nasa.gov (8.6.12/8.6.12) id NAA28660; Fri, 7 Jul 1995 13:56:50 -0400 Date: Fri, 7 Jul 1995 13:56:49 -0400 (EDT) From: "Michael C. Newell" To: "Rashid Karimov." cc: chuckr@Glue.umd.edu, FreeBSD-Questions@freefall.cdrom.com Subject: Re: Using No-break Power Systems In-Reply-To: <199507071722.NAA23818@haven.ios.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: questions-owner@FreeBSD.org Precedence: bulk On Fri, 7 Jul 1995, Rashid Karimov. wrote: > Usually UPS'es come standard with DB-9 like socket , on > which there are 2 or 3 pins ( TTL) which change the voltage > on them during power failures - so it's pretty easy to analize > the output from them via some simple program ( say using the > pin which goes to 1 when there is problem as DCD, so you'll > be able to open the port only when the power disapears) and > take appropriate actions w/o wroting actual device driver :) > Even dumb( back-up ) UPS often have this connectors. Neither of the two Tripp-Lite units that I own have such a connector. I've been sorely tempted to open the box and add bufferred lines off the front panel LEDs, but that would be a personal hack and would most likely void any warranties... In my case I wasn't too concerned about this feature because (a) the outages here tend to be very short and (b) if the systems do go down gracelessly it's not a really big deal to me. However, if you DO require this feature then you need to make sure it's present on the unit you buy... For me it was better to buy a unit with higher capacity at the same price and sacrifice the status output. Thanks, Mike +--------------------------------------+------------------------------------+ |Mike Newell | The opinions expressed herein are | |NASA Science Internet Network Systems | my own, and do not necessarily | |Sterling Software, Inc. | reflect those of the NSI program, | |MNewell@nsipo.nasa.gov | Sterling Software, NASA, or anyone | |+1-202-434-8954 | else. | +--------------------------------------+------------------------------------+ | work: http://www.eco.nsi.nasa.gov/~mnewell | | home: http://www.newell.arlington.va.us | +---------------------------------------------------------------------------+