From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 18 Apr 2002 20:10:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 18 Apr 2002 20:10:58 -0400 Received: from h24-67-14-151.cg.shawcable.net ([24.67.14.151]:9461 "EHLO webber.adilger.int") by vger.kernel.org with ESMTP id ; Thu, 18 Apr 2002 20:10:58 -0400 From: Andreas Dilger Date: Thu, 18 Apr 2002 18:09:28 -0600 To: "Adrian V. Bono" Cc: linux-kernel@vger.kernel.org Subject: Re: something weird on Linux 2.4.17 on an IBM Thinkpad T20 Message-ID: <20020419000928.GB28956@turbolinux.com> Mail-Followup-To: "Adrian V. Bono" , linux-kernel@vger.kernel.org In-Reply-To: <3CBF6225.6050605@tmg99.ntes.nec.co.jp> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.27i X-GPG-Key: 1024D/0D35BED6 X-GPG-Fingerprint: 7A37 5D79 BF1B CECA D44F 8A29 A488 39F5 0D35 BED6 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Apr 19, 2002 09:17 +0900, Adrian V. Bono wrote: > While working in X on kernel 2.4.17 on an IBM Thinkpad T20, sometimes > the mouse pointer would just gravitate all by itself, without my moving > the mouse or pointing stick, upwards. The first time that happened, i > was coding in an xterm when suddenly, window focus shifted to another > window and i noticed the mouse pointer was moving upwards by itself. > Anyone else notice this? This is common to all thinkpads (or other laptops which have trackpoint devices) and also happens under Windows. The cause is related to automatic compensation for the centering of the trackpoint. Early trackpoint devices didn't have automatic centering and I remember replacing more than a few keyboards because the mouse would start drifting by itself. Later trackpoints have automatic centering, but if you hold onto the trackpoint for a long time (causing the "center" to be offset by some amount) and then let go, it will settle back to the "old center" and the cursor will drift for a few seconds until the automatic centering kicks in again. Moral of the story - don't touch the trackpoint when you aren't doing anything with it. Cheers, Andreas -- Andreas Dilger http://www-mddsp.enel.ucalgary.ca/People/adilger/ http://sourceforge.net/projects/ext2resize/