From owner-freebsd-arch@FreeBSD.ORG Fri Aug 31 12:27:32 2007 Return-Path: Delivered-To: arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 566D816A419 for ; Fri, 31 Aug 2007 12:27:32 +0000 (UTC) (envelope-from alexander@leidinger.net) Received: from redbull.bpaserver.net (redbullneu.bpaserver.net [213.198.78.217]) by mx1.freebsd.org (Postfix) with ESMTP id CFEC513C469 for ; Fri, 31 Aug 2007 12:27:31 +0000 (UTC) (envelope-from alexander@leidinger.net) Received: from outgoing.leidinger.net (p54A55A26.dip.t-dialin.net [84.165.90.38]) by redbull.bpaserver.net (Postfix) with ESMTP id 8CC682E332; Fri, 31 Aug 2007 14:01:03 +0200 (CEST) Received: from webmail.leidinger.net (webmail.Leidinger.net [192.168.1.102]) by outgoing.leidinger.net (Postfix) with ESMTP id 15BF25B4996; Fri, 31 Aug 2007 14:01:01 +0200 (CEST) Received: (from www@localhost) by webmail.leidinger.net (8.13.8/8.13.8/Submit) id l7VC10wU060273; Fri, 31 Aug 2007 14:01:00 +0200 (CEST) (envelope-from Alexander@Leidinger.net) Received: from proxy.Leidinger.net (proxy.Leidinger.net [192.168.1.103]) by webmail.leidinger.net (Horde MIME library) with HTTP; Fri, 31 Aug 2007 14:01:00 +0200 Message-ID: <20070831140100.zphn2zsxzb408okc@webmail.leidinger.net> X-Priority: 3 (Normal) Date: Fri, 31 Aug 2007 14:01:00 +0200 From: Alexander Leidinger To: Poul-Henning Kamp References: <8412.1188553371@critter.freebsd.dk> In-Reply-To: <8412.1188553371@critter.freebsd.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; DelSp="Yes"; format="flowed" Content-Disposition: inline Content-Transfer-Encoding: quoted-printable User-Agent: Internet Messaging Program (IMP) H3 (4.1.4) / FreeBSD-7.0 X-BPAnet-MailScanner-Information: Please contact the ISP for more information X-BPAnet-MailScanner: Found to be clean X-BPAnet-MailScanner-SpamCheck: not spam, SpamAssassin (not cached, score=-14.9, required 8, BAYES_00 -15.00, RDNS_DYNAMIC 0.10) X-BPAnet-MailScanner-From: alexander@leidinger.net X-Spam-Status: No Cc: arch@freebsd.org Subject: Re: Proof of concept: soundcard as console device X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 31 Aug 2007 12:27:32 -0000 Quoting Poul-Henning Kamp (from Fri, 31 Aug 2007 =20 09:42:51 +0000): > > Yesterday while I was futzing with my new laptop and ACPI suspend/resume, > I once again found myself cursing the nutjob who took away our serial > ports. Lucky those people with a firewire interface... > Then my mind wandered around a bit and suddenly it struck me: all > modern hardware have built in AC97 sound hardware, and it offers a > channel with a pretty decent bandwidth. You are too late, Intel is moving to HDA and away of AC97. And it =20 seems everyone except Creative is following (there are companies with =20 their own interfaces (VIA envy24), but often they provide a HDA =20 chipset too). Creative doesn't really matter, as they don't provide =20 docs and everyone tries to avoid it. > This morning I ran a simple experiment, from userland, but the > result show clearly that the idea is workable. > > The transmission format I used: send a negative transient to start > a character and after N samples, send a positive transient, where > N is the ASCII value of the character + a small constant. Some cards have digital-out/in (SPDIF), maybe it's an option for you. Bye, Alexander. --=20 Never give an inch! http://www.Leidinger.net Alexander @ Leidinger.net: PGP ID =3D B0063FE7 http://www.FreeBSD.org netchild @ FreeBSD.org : PGP ID =3D 72077137