From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 8 Jun 2001 12:28:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 8 Jun 2001 12:28:46 -0400 Received: from olsinka.site.cas.cz ([147.231.11.16]:2178 "EHLO twilight.suse.cz") by vger.kernel.org with ESMTP id ; Fri, 8 Jun 2001 12:28:34 -0400 Date: Fri, 8 Jun 2001 18:28:07 +0200 From: Vojtech Pavlik To: Pavel Machek Cc: linux-kernel@vger.kernel.org Subject: Re: [driver] New life for Serial mice Message-ID: <20010608182807.B2083@suse.cz> In-Reply-To: <20010606125556.A1766@suse.cz> <20010606232133.E38@toy.ucw.cz> <20010608181521.A1998@suse.cz> <20010608182046.H13825@atrey.karlin.mff.cuni.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20010608182046.H13825@atrey.karlin.mff.cuni.cz>; from pavel@suse.cz on Fri, Jun 08, 2001 at 06:20:46PM +0200 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 08, 2001 at 06:20:46PM +0200, Pavel Machek wrote: > Hi! > > > > > If you still have your 3-button MouseSystems (or any other serial) mouse > > > > somewhere in your driver, forgotten becase of the incredibly slow update > > > > rate causing so much jumping of the pointer on the screen that it is > > > > unusable, you may want to pull it out and give it a try. > > > > > > > > Or if you're still using it with some old 486 computer, this driver is > > > > for you. > > > > > > > > What it does is that it enhances the update rate from 24 (with current > > > > GPM and X drivers) to 96. This is almost what the best USB mice do. > > > > > > What's the "prediction" stuff? Does it mean you are guessing some values > > > by interpolation? > > > > Extrapolation, yes. > > Can't it make mouse jump forward and back when user suddenly stops? In theory - yes. It doesn't seem to be a problem in practice, though. It'll happen when a user slows down the mouse pointer motion faster than exponentially (base 2). I haven't been able to stop that fast. > > > [If so, what kind of update rate would it do on USB?] > > > > It wouldn't make any difference - on USB you always get whole packets, > > while over serial port the data is processed byte by byte and thus we > > know a little of the information before the whole packet arrives. > > Ouch, nice trick! Most importantly - it makes serial mice usable. -- Vojtech Pavlik SuSE Labs