From owner-freebsd-hackers@FreeBSD.ORG Fri Jan 1 20:57:30 2010 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 09521106566B for ; Fri, 1 Jan 2010 20:57:30 +0000 (UTC) (envelope-from stb@lassitu.de) Received: from koef.zs64.net (koef.zs64.net [212.12.50.230]) by mx1.freebsd.org (Postfix) with ESMTP id 9C2D28FC08 for ; Fri, 1 Jan 2010 20:57:29 +0000 (UTC) Received: from localhost by koef.zs64.net (8.14.3/8.14.3) with ESMTP id o01KSUfO065562 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO) for ; Fri, 1 Jan 2010 21:28:31 +0100 (CET) (envelope-from stb@lassitu.de) (authenticated as stb) From: Stefan Bethke Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Date: Fri, 1 Jan 2010 21:28:30 +0100 Message-Id: <8E9BCE63-C37A-438C-94D8-7AA86B9F6597@lassitu.de> To: freebsd-hackers@freebsd.org Mime-Version: 1.0 (Apple Message framework v1077) X-Mailer: Apple Mail (2.1077) Subject: TEMPer USB Thermometer X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 01 Jan 2010 20:57:30 -0000 Various outfits including Brando are selling a cheap-ish USB thermometer = named =93TEMPer=94. (I need one to monitor my home server closet.) I've put together a small command line utility that reads out the = temperature from the LM75 sensor in the TEMPer: = http://wiki.zs64.net/TEMPer_USB_Thermometer To run it, you will need to have the driver for WinChipHead = USB-to-serial controller loaded (uchcom(8) on FreeBSD). It puts the LM75 into 12-bit resolution mode (about one measurement per = second) and outputs temperature data once per second in degrees Celcius. The LM75 thermostat is connected to an LED, so you can use that as an = indicator of temperature. Note that driving the LED dissipates enough = power (probably through the current-limiting resistor) that the measured = temperature rises by two degrees. usage: temper [-d device] [-h high] [-l low] [-n count] -d device USB serial port of the TEMPer -h high thermostat on temperature -l low thermostat off temperature -n count number of readings to take, <0 is infinite If the high temperature is below the low temperature, operation of the thermostat is reversed, and the output is turned on when the measured temperature is below the threshold. Enjoy! Stefan --=20 Stefan Bethke Fon +49 151 14070811