From owner-freebsd-hackers@freebsd.org Fri Sep 30 15:32:21 2016 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 5E24CC02E1D for ; Fri, 30 Sep 2016 15:32:21 +0000 (UTC) (envelope-from hps@selasky.org) Received: from mail.turbocat.net (heidi.turbocat.net [88.198.202.214]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 24EEB8B8; Fri, 30 Sep 2016 15:32:20 +0000 (UTC) (envelope-from hps@selasky.org) Received: from laptop015.home.selasky.org (unknown [62.141.129.119]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.turbocat.net (Postfix) with ESMTPSA id 6C68C1FE022; Fri, 30 Sep 2016 17:32:18 +0200 (CEST) Subject: Re: Logitech G510s keyboard fail. To: lidl@FreeBSD.org, freebsd-hackers@freebsd.org References: <336fa405-dc7d-4715-bbc9-6f1cbf049bbd@FreeBSD.org> From: Hans Petter Selasky Message-ID: <9afde4c1-714c-cc56-56b7-6901198028f1@selasky.org> Date: Fri, 30 Sep 2016 17:37:11 +0200 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <336fa405-dc7d-4715-bbc9-6f1cbf049bbd@FreeBSD.org> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Sep 2016 15:32:21 -0000 On 09/30/16 17:29, Kurt Lidl wrote: > > The number of simultaneous keypresses one can track is related to > the size of the bitmap. With the 16 bytes of bitmap, you get up > up to 128 simultaneous key-presses, etc... The 32 bytes of bitmap > get you up to 256 bits of presence detection. I don't know if > there's a 128 byte variant of the bitmap support packet or not. > Someone would have to do some usb low-level debugging to figure that > out... It seems straightforward - there's just a byte in the middle > of the bitmap packet support that says how many bytes of bitmap > data there are present. Hi Kurt, Typically USB full speed does not go beyond 64-bytes per packet. Possibly we should add support for the bitmap mode of USB keyboards. Your understanding is correct. --HPS