[linux-dvb] Re: dvbtune / Nova-T unable to lock on frequencyproblems

[Bruno Prior <bruno@rpgd.uklinux.net>]

Gregor Lawatscheck wrote:
> > 1. dvbtune -i gives me no information ("Nothing to read from fd_pat...")
> That's usually what I get when I have the wrong QAM and FEC for the 
> transponder. It locks on, but just doesn't read anything useful. I've 
> seen you're supplying qam and fec on the command line and for all but 
> the ITV and C5 transmitter QAM 16 and FEC 3_4 should be right. ITV / C5 
> have QAM 64 and FEC 2_3.
I am on the Crystal Palace transponder, so I use 505833 for BBC and 481833 
for ITV (you are welcome to check, but I understand from earlier emails that 
this is correct). So:

[root@localhost dvbtune]# ./dvbtune -f 505833 -qam 16 -cr 3_4 -i
Using DVB card "Grundig 29504-401"
tuning DVB-T (in United Kingdom) to 505833000 Hz
polling....
Getting frontend event
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Bit error rate: 80
Signal strength: 12079
SNR: 59624
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
<transponder type="T" freq="505833000">
Nothing to read from fd_sdt
</transponder>

[root@localhost dvbtune]# ./dvbtune -f 481833 -qam 64 -cr 2_3 -i
Using DVB card "Grundig 29504-401"
tuning DVB-T (in United Kingdom) to 481833000 Hz
polling....
Getting frontend event
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Bit error rate: 411
Signal strength: 12079
SNR: 54227
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
<transponder type="T" freq="481833000">
Nothing to read from fd_sdt
</transponder>

Unless you can spot an error, this seems to be the right QAM and FEC 
settings for the right channels, but still no info.

I checked my tzap channels.conf, and BBC had the "wrong" QAM and FEC (I 
think I borrowed an old one from somewhere - didn't the BBC change this?). 
So I tried with the "wrong" settings, and this is what I got:

[root@localhost dvbtune]# ./dvbtune -f 505833 -qam 64 -cr 2_3 -i
Using DVB card "Grundig 29504-401"
tuning DVB-T (in United Kingdom) to 505833000 Hz
polling....
Getting frontend event
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Bit error rate: 53
Signal strength: 12079
SNR: 59624
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
<transponder type="T" freq="505833000">
<service id="25664" ca="0">
<description tag="0x48" type="1" provider_name="EMAP" service_name="The HITS" />
</service>
<service id="25728" ca="0">
<description tag="0x48" type="1" provider_name="MTV Europe" 
service_name="TMF" />
</service>
<service id="25792" ca="0">
<description tag="0x48" type="1" provider_name="UKTV" 
service_name="UKBrightIdeas" />
</service>
<service id="25856" ca="0">
<description tag="0x48" type="1" provider_name="Flextech" service_name="f tn" />
</service>
<service id="25920" ca="0">
<description tag="0x48" type="1" provider_name="...." service_name="Ch 22" />
</service>
<service id="25984" ca="0">
<description tag="0x48" type="1" provider_name="...." service_name="Ch 32" />
</service>
<service id="26048" ca="0">
<description tag="0x48" type="1" provider_name="...." service_name="Ch 44" />
</service>
<service id="26176" ca="0">
<description tag="0x48" type="2" provider_name="EMAP" service_name="Kiss" />
</service>
<service id="26240" ca="0">
<description tag="0x48" type="2" provider_name="EMAP" service_name="Smash 
Hits!" />
</service>
<service id="26304" ca="0">
<description tag="0x48" type="2" provider_name="EMAP" service_name="Kerrang!" />
</service>
<service id="26368" ca="0">
<description tag="0x48" type="2" provider_name="GMG" service_name="jazz fm" />
</service>
<service id="26432" ca="0">
<description tag="0x48" type="2" provider_name="Oneword" 
service_name="oneword" />
</service>
<service id="26496" ca="0">
<description tag="0x48" type="2" provider_name="BBC" service_name="BBC World 
Sv." />
</service>
</transponder>

Then I tried exactly the same thing again and got this:

[root@localhost dvbtune]# ./dvbtune -f 505833 -qam 64 -cr 2_3 -i
Using DVB card "Grundig 29504-401"
tuning DVB-T (in United Kingdom) to 505833000 Hz
polling....
Getting frontend event
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Bit error rate: 59
Signal strength: 12079
SNR: 59624
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
<transponder type="T" freq="505833000">
Nothing to read from fd_sdt
</transponder>

And several more tries never got any information again. So I went back to 
the "right" QAM and FEC settings, and got (variously) information for the 
same channels as above, the Sky channels or nothing. When I tried with the 
ITV frequency (481833) and QAM 64 and FEC 2_3, I got information on the BBC 
channels. This is exactly the behaviour I got on my wife's computer (see 
message to list on 13 Jan). It is both inconsistent and illogical.

Still, this was more than I had had since I took the card out of my wife's 
computer, so I decided to have another go with dvbstream. Lo and behold, I got:

[root@localhost dvbstream]# ./dvbstream -f 505833 -qam 16 -cr 3_4 -ps 600 
601 -o | mplayer -
dvbstream v0.4pre3 - (C) Dave Chapman 2001
Released under the GPL.
Latest version available from http://www.linuxstb.org/
Using DVB card "Grundig 29504-401"
tuning DVB-T (in United Kingdom) to 505833000 Hz
Using GNU internationalization
Original domain: messages
Original dirname: /usr/share/locale
Current domain: mplayer
Current dirname: /usr/share/locale

MPlayer 0.90rc4-3.2.1 (C) 2000-2003 Arpad Gereoffy (see DOCS)

CPU: Intel  (Family: 8, Stepping: 7)
Detected cache-line size is 64 bytes
CPUflags:  MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1
Compiled with Runtime CPU Detection - WARNING - this is not optimal!
To get best performance, recompile MPlayer with --disable-runtime-cpudetection
Reading config file /etc/mplayer/mplayer.conf
Reading config file /root/.mplayer/config
Reading /root/.mplayer/codecs.conf: can't open '/root/.mplayer/codecs.conf': 
No such file or directory
Reading /etc/mplayer/codecs.conf: 50 audio & 135 video codecs
font: can't open file: /root/.mplayer/font/font.desc
Font /usr/share/mplayer/font/font.desc loaded successfully! (206 chars)
Using Linux hardware RTC timing (1024Hz).
Can't open input config file /root/.mplayer/input.conf : No such file or 
directory
Input config file /etc/mplayer/input.conf parsed : 52 binds
Opening joystick device /dev/input/js0
Can't open joystick device /dev/input/js0 : No such file or directory
Can't init input joystick
Setting up LIRC support...
mplayer: could not connect to socket
mplayer: No such file or directory
Failed to open LIRC support.
You will not be able to use your remote control.

Playing -
Reading from stdin...
Cache fill:  0.00% (0 bytes)    polling....
Cache fill:  0.00% (0 bytes)    Getting frontend event
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Bit error rate: 65
Signal strength: 12079
SNR: 59624
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI FE_HAS_SYNC
Output to stdout
Streaming 2 streams
Cache fill:  0.00% (0 bytes)    Audiostream: Layer: 2  BRate: 256 kb/s 
Freq: 48.0 kHz
Cache fill:  0.00% (0 bytes)    Videostream: ASPECT: 16:9  Size = 720x576 
FRate: 25 fps  BRate: 15.00 Mbit/s
Cache fill: 19.92% (1671168 bytes)    MPEG-PS file format detected.
VIDEO:  MPEG2  720x576  (aspect 3)  25.00 fps  18750.0 kbps (2343.8 kbyte/s)
==========================================================================
Opening audio decoder: [mp3lib] MPEG layer-2, layer-3
MP3lib: init layer2&3 finished, tables done
AUDIO: 48000 Hz, 2 ch, 16 bit (0x10), ratio: 32000->192000 (256.0 kbit)
Selected audio codec: [mp3] afm:mp3lib (mp3lib MPEG layer-2, layer-3)
==========================================================================
vo: X11 running at 1024x768 with depth 16 and 16 bpp (":0.0" => local display)
Disabling DPMS
==========================================================================
Opening video decoder: [mpegpes] MPEG 1/2 Video passthrough
VDec: vo config request - 720 x 576 (preferred csp: Mpeg PES)
Could not find matching colorspace - retrying with -vop scale...
Opening video filter: [scale]
The selected video_out device is incompatible with this codec.
VDecoder init failed :(
Opening video decoder: [libmpeg2] MPEG 1/2 Video decoder v2.0
libmpeg2: Using MMXEXT for IDCT transform
libmpeg2: Using MMXEXT for motion compensation
VDec: vo config request - 720 x 576 (preferred csp: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 1.78:1 - prescaling to correct movie aspect.
VO: [xv] 720x576 => 1024x576 Planar YV12  [fs]
Selected video codec: [mpeg12] vfm:libmpeg2 (MPEG 1 or 2 (libmpeg2))
==========================================================================
Checking audio filter chain for 48000Hz/2ch/16bit -> 48000Hz/2ch/16bit...
AF_pre: af format: 2 bps, 2 ch, 48000 hz, little endian signed int
AF_pre: 48000Hz 2ch Signed 16-bit (Little-Endian)
audio_setup: Can't open audio device /dev/dsp: Device or resource busy
alsa-init: testing and bugreports are welcome.
alsa-init: requested format: 48000 Hz, 2 channels, Signed 16-bit (Little-Endian)
alsa-init: no soundcards found: Success
AO: [arts] can't connect to aRts soundserver
AO: [esd] esd_open_sound failed: No such file or directory
ao_nas: init(): Can't open nas audio server -> nosound
SDL: Samplerate: 48000Hz Channels: Stereo Format Signed 16-bit (Little-Endian)
SDL: Unable to open audio: No available audio device
AO: [null] 48000Hz 2ch Signed 16-bit (Little-Endian) (2 bps)
Building audio filter chain for 48000Hz/2ch/16bit -> 48000Hz/2ch/16bit...
Starting playback...
@@@ libmpeg2 returned from sig11... (bad file?) @@@  11% 15%  1.0% 0 0 71%%
@@@ libmpeg2 returned from sig11... (bad file?) @@@  10% 15%  0.9% 0 0 67%
@@@ libmpeg2 returned from sig11... (bad file?) @@@
@@@ libmpeg2 returned from sig11... (bad file?) @@@
@@@ libmpeg2 returned from sig11... (bad file?) @@@
@@@ libmpeg2 returned from sig11... (bad file?) @@@
@@@ libmpeg2 returned from sig11... (bad file?) @@@
@@@ libmpeg2 returned from sig11... (bad file?) @@@
@@@ libmpeg2 returned from sig11... (bad file?) @@@
@@@ libmpeg2 returned from sig11... (bad file?) @@@

And a picture (no sound) that was initially badly broken up but settled down 
after 5 seconds. This is the first success I have had with this card. The 
only things I have done since the last attempts yesterday are:

(a) I chowned, chgrped and chmoded all the files under drivers/ to be owned 
by root, in my personal group and make the file permissions 664 (I wanted to 
try running make insmod as me rather than root, but I still couldn't because 
my user doesn't have execute permissions to insmod).

(b) The aerial socket is a double - TV and FM with a DAB tuner in the FM 
socket, and I had unplugged the DAB tuner.

Having repeated this a few times to make sure that this would work 
consistently without the DAB tuner (and in the process getting sound as well 
as a picture), I plugged the tuner aerial back in and ran the command again. 
This worked as well as without the tuner plugged in, so I conclude it is 
nothing to do with the aerial.

That leaves changing the permissions on the files in drivers/ as the only 
difference between working today and not working yesterday. I have been 
suspicious of permissions, but assumed the problem would be permissions on 
the devices. It didn't occur to me that the problem might be permissions on 
the driver files, particularly as I was doing all this as root. But 
Mandrake's setup seems to treat root in a non-standard way - this is not the 
first time that I have seen root prevented from doing things that I thought 
it should be able to do (i.e. everything). Does file permissions sound like 
a possible cause of my problems?

I still can't run this as anyone other than root, so I think I have more to 
work out regarding the right permissions to get this working.

> > Which never moves past this point. So it seems that dvbstream is not 
> > actually streaming anything successfully to stdout, despite saying 
> > that it is.
> are you selecting the right PIDs on command line. For BBC-1 for example 
> these should be 600 for video and 601 for audio (I believe these are the 
> same around the country).
Yes, I am (see above).

Cheers,

Bruno



--
Info:
To unsubscribe send a mail to listar@linuxtv.org with "unsubscribe linux-dvb" as subject.