From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mta5.srv.hcvlny.cv.net ([167.206.4.200]) by www.linuxtv.org with esmtp (Exim 4.63) (envelope-from ) id 1KplXv-0005cb-6v for linux-dvb@linuxtv.org; Tue, 14 Oct 2008 17:10:54 +0200 Received: from steven-toths-macbook-pro.local (ool-18bfe594.dyn.optonline.net [24.191.229.148]) by mta5.srv.hcvlny.cv.net (Sun Java System Messaging Server 6.2-8.04 (built Feb 28 2007)) with ESMTP id <0K8Q0076HI52I000@mta5.srv.hcvlny.cv.net> for linux-dvb@linuxtv.org; Tue, 14 Oct 2008 11:10:16 -0400 (EDT) Date: Tue, 14 Oct 2008 11:10:14 -0400 From: Steven Toth In-reply-to: <200810141451.02941.hftom@free.fr> To: Christophe Thommeret Message-id: <48F4B656.6010404@linuxtv.org> MIME-version: 1.0 References: <200810141133.36559.hftom@free.fr> <1985.1223980189@kewl.org> <200810141451.02941.hftom@free.fr> Cc: linux-dvb@linuxtv.org Subject: Re: [linux-dvb] [PATCH] cx24116 DVB-S modulation fix List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: quoted-printable Sender: linux-dvb-bounces@linuxtv.org Errors-To: linux-dvb-bounces+mchehab=infradead.org@linuxtv.org List-ID: Christophe Thommeret wrote: > Le Tuesday 14 October 2008 12:29:49 Darron Broad, vous avez =E9crit : >> In message <200810141133.36559.hftom@free.fr>, Christophe Thommeret wrot= e: >> >> hi >> >>> Hi, >>> >>> This patch makes cx24116 to behave like other dvb-s frontends. >> Unlike most DVB-S cards the those with a cx24116 use S2API >> this makes them somewhat different. >> >>> This is needed especially because QAM_AUTO is used in a lot of scan fil= es. >> What scan files are you referring to? The >> cx24116 only does PSK, not AM. QAM_AUTO >> doesn't sound right. the cx24116 can't >> auto detect anything, but that's another >> story... > = > dvbscan initial tuning data files for DVB-S don't have an entry for = > modulation. So an app like kaffeine simply set modulation to QAM_AUTO. > Why not QPSK, you ask? Simply because DVB-S standard allows QPSK and 16QA= M. = > Maybe there is not a single 16QAM TP all over the world, but it's still a = > valid modulation for DVB-S. > So, we set modulation to QAM_AUTO when it's unknown/unspecified, like in = > dvbscan files (those being also used by kaffeine). And it works pretty we= ll, = > just because most dvb-s can only do QPSK and so force modulation to QPSK = > instead of returning a notsup. > See this as software QAM_AUTO :) I've only glanced briefly at the patch but setting the modulation type = to QAM_AUTO, and expecting the card to support it I think is a bad idea. I can accept the argument that the current driver will not accept 16QAM, = but that's not the problem being discussed. (I'll address this in a = separate patch) Call DTV_CLEAR should also default your rolloff to 3.5. Let's investigate a better approach. kaffeine should be working well already, with the current code. Unless = it was recently broken - in which case please discuss. - Steve _______________________________________________ linux-dvb mailing list linux-dvb@linuxtv.org http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb