From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mailout-de.gmx.net ([213.165.64.23]:41951 "HELO mailout-de.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755162Ab2HNIx5 (ORCPT ); Tue, 14 Aug 2012 04:53:57 -0400 Message-ID: <502A1221.8020804@gmx.de> Date: Tue, 14 Aug 2012 10:53:53 +0200 From: Reinhard Nissl MIME-Version: 1.0 To: linux-media@vger.kernel.org Subject: STV0299: reading property DTV_FREQUENCY -- what am I expected to get? Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Hi, it seems that my 9 years old LNBs got some drift over time, as tuning takes quite a while until I get a lock. So I thought I could compensate this offset by adjusting VDR's diseqc.conf. Therefore I first hacked some logging into VDR's tuner code to read and output the above mentioned property once it got a lock after tuning. As VDR's EPG scanner travels over all transponders when idle, I get offset values for all transponders and can then try to find some average offset to put into diseqc.conf. So here are several "travel" results for a single transponder ordered by Delta: Sat. Pol. Band Freq (MHz) Set Freq (MHz) Get Delta (MHz) S13,0E H H 11938 11930,528 -7,472 S13,0E H H 11938 11936,294 -1,706 S13,0E H H 11938 11938,917 0,917 S13,0E H H 11938 11939,158 1,158 S13,0E H H 11938 11939,906 1,906 S13,0E H H 11938 11939,965 1,965 S13,0E H H 11938 11940,029 2,029 S13,0E H H 11938 11940,032 2,032 S13,0E H H 11938 11940,103 2,103 S13,0E H H 11938 11940,112 2,112 S13,0E H H 11938 11940,167 2,167 S13,0E H H 11938 11941,736 3,736 S13,0E H H 11938 11941,736 3,736 S13,0E H H 11938 11941,736 3,736 S13,0E H H 11938 11942,412 4,412 S13,0E H H 11938 11943,604 5,604 S13,0E H H 11938 11943,604 5,604 S13,0E H H 11938 11943,604 5,604 S13,0E H H 11938 11945,472 7,472 S13,0E H H 11938 11945,472 7,472 S13,0E H H 11938 11945,472 7,472 S13,0E H H 11938 11945,472 7,472 S13,0E H H 11938 11945,472 7,472 S13,0E H H 11938 11945,472 7,472 S13,0E H H 11938 11945,472 7,472 S13,0E H H 11938 11945,777 7,777 S13,0E H H 11938 11945,777 7,777 S13,0E H H 11938 11945,777 7,777 S13,0E H H 11938 11945,777 7,777 I really wonder why Delta varies that much, and there are other transponders in the same band which have no larger deltas then 3 MHz. So is it at all possible to determine LNB drift in that way? My other device, a STB0899, always reports the set frequency. So it seems driver dependent whether it reports the actually locked frequency found by the zig-zag-algorithm or just the set frequency to tune to. Thanks in advance for any replies. Bye. -- Dipl.-Inform. (FH) Reinhard Nissl mailto:rnissl@gmx.de