From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Ionescu Subject: Re: question about ACPI & Smart Batteries Date: Fri, 13 Aug 2004 01:40:34 +0300 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: References: <20040812222936.GD30862@miramar.cse.ucsc.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Return-path: Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Hi Cintia, In CM case I think that when you look into /proc/acpi/battery/BAT0/state, you get the instantaneous value. So the state file is not updated unless you look in it, and then you get the values at that moment, because the APCI code will just call _BST method to tell you the actual values. So, I think you can trust those values as being pretty accurate. Paul On Thu, 12 Aug 2004 15:29:36 -0700, Cintia B. Margi wrote: >> For a CM battery, the OS can poll the battery state by calling _BST, or >> set a trip point (via _BTP) and the OS will get an interrupt when the >> battery crosses that trip. > > I do not want to set a trip point, but I would like to monitor the > battery discharge process... I want to characterize the battery > discharge behavior under different tasks, so I intend to monitor the > battery voltage and the discharge rate (which I can obtain from > /proc/acpi/battery/BAT0/state). What I would like to know is how often > the state file is updated and how accurate these values are. Any idea > where I can get this info? > > Thanks, > > Cintia ------------------------------------------------------- SF.Net email is sponsored by Shop4tech.com-Lowest price on Blank Media 100pk Sonic DVD-R 4x for only $29 -100pk Sonic DVD+R for only $33 Save 50% off Retail on Ink & Toner - Free Shipping and Free Gift. http://www.shop4tech.com/z/Inkjet_Cartridges/9_108_r285