From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from 7of9.schinagl.nl ([88.159.158.68]:51390 "EHLO 7of9.schinagl.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753673Ab2GQKtt (ORCPT ); Tue, 17 Jul 2012 06:49:49 -0400 Received: from [10.2.0.242] (unknown [10.2.0.242]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by 7of9.schinagl.nl (Postfix) with ESMTPSA id 75D6F24422 for ; Tue, 17 Jul 2012 12:50:16 +0200 (CEST) Message-ID: <50053610.9010909@schinagl.nl> Date: Tue, 17 Jul 2012 11:53:20 +0200 From: Oliver Schinagl MIME-Version: 1.0 To: linux-media@vger.kernel.org Subject: Re: TechnoTrend Budget CI stutters and often fails at tuning encrypted channel. References: <500522AE.9020900@schinagl.nl> In-Reply-To: <500522AE.9020900@schinagl.nl> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 17-07-12 10:30, Oliver Schinagl wrote: > Hi list, > > I have been using a tt1500, a saa7146 PCI DVB-T tuner for well over a > year now. Running gentoo 64bit tracking the ~amd64 branch (that only > get bi-monthly upgraded) I've been always more or less up to date. > > This card however has never properly worked. I've been running vdr > 1.6.* since that is what's stably in gentoo. Whilst writing this down > I realized I still have to test me-tv to double check my findings. > > Some background info. Here in NL we have 4 FTA channels and about 20 > conax encrypted channels that the CAM in the CI module decrypts. I > have two smartcards, of which one is only in active use at the moment. > > When changing channels between the FTA channels, the first 'bug' > occurs. Somtimes (not predictably or anything, about 50% of the > channel changes) sound stutters the first few seconds, upto 30 seconds > sometimes. It sounds almost if the sound is being fed through some > sort of PWM, that slowly catches up. So first you hear 1 second of > audio, 3 seconds of nothing, then 1 second of audio again, then 2 > seconds of nothing etc. This audio delay is random. E.g. sometimes it > stutters for about 30 seconds while it has a hard time to catch up, > other times the audio needs only 2 or 3 seconds to catch up. Very > occasionally it instantly works right. The stuttering appears to be > worse on encrypted channels. > > Encrypted channels has the additional annoyance, that quote often, an > entire channel is not available. That is, every channel in its bouqet. > Simply waiting on that channel for about a minute or two, mysteriously > brings the unavailable channel up. Allthough it 'feels' like changing > channel helps this fix faster, it's just a placebo effect if you ask > me ;) > > I cannot safely say that the same skipping happens to the video, I > have not noticed it really. I have checked signal strength etc and > though the strength is only at 55%, the SNR is at 99% quite stable and > the BER (unrecoverable errors? are at 0). If for some reason there is > interferance, bad whether, blocked antenna, then the BER goes up > followed by distorted imagery and with really bad signal bad audio as > well (humans are more sensitive to bad audio iirc). > > I'm not sure what to profile, where to enable debugging, what logs to > check or what to do to help 'fix' this. > > lspci output: > 00:0a.0 Multimedia controller: Philips Semiconductors SAA7146 (rev 01) > Subsystem: Technotrend Systemtechnik GmbH DVB T-1500 > Flags: bus master, medium devsel, latency 32, IRQ 18 > Memory at f0162000 (32-bit, non-prefetchable) [size=512] > Kernel drive in use: budget_ci dvb > > /proc/interrupts > 18: 499 107651 IO-APIC-fasteoi saa7146 (0) > > Tuner: tda10046h dvb-t, firmware revision 20 > > > Thank you for your time, > oliver P.S. I forgot to mention, that once tuned to a channel, I can receive (and decode) it fine for many hours. I think the longest I had one channel up was about 8 hours or so without issue. A dvb-t radio channel (thus not dab) i had up for even longer, so once it goes, it goes on happily forever!