[linux-dvb] patch "budget-av: Remove polarity switching of the clock for the DVB-C cards" causes corrupt stream

Matthias Dahl mldvb at mortal-soul.de
Sun May 20 14:44:31 CEST 2007

On Saturday 19 May 2007 23:45:12 e9hack wrote:

> Did you switch to a FTA channel or did you also remove the CI physical from
> the card?

Tried both (with and without CI attached to the knc one)... the result was the 

> Than you have another problem. If you get such a warning with a buffer of
> 658kB, interrupts wasn't deliver to the dvb-driver for more than 85..106ms.

I know. When I first ran into this problem, I spent -a lot of time- debugging 
it. I tracked it down to the nvidia binary only driver. With the nv driver, I 
wasn't able to cause any vpeirq msgs. Unfortunately I need the binary only 
driver for computer graphics stuff (no gaming). So... once I figured that 
increasing the bufsize to 1410 solves the symptoms, I could live with it.

Tried almost everything to solve the problem itself... but that's another 
topic I guess. :-) [just a note: seems like the nvidia driver holds an 
interrupt for too long when doing a XOrg <-> VT switch]

> The windows driver uses a small buffer (188kB), in odd/even buffer
> mode.

Interesting. Just tried to cause a corrupt stream there without any luck. But 
that's hardly representative because I don't use windows at all. It's just 
there in case I need it for university or work.

> Can you create such a dump again?

Just did. Attached you find several dumps... one without the CI attached to 
the card (tuned into a FTA channel), a few others with and without the CI 
initialised (but attached to the card). The filename should be

Like always, if you need anything, please let me know.

Have a nice sunday,
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ci_encrypted_channel.txt.gz
Type: application/x-gzip
Size: 1646 bytes
Desc: not available
Url : http://www.linuxtv.org/pipermail/linux-dvb/attachments/20070520/af4cfff9/ci_encrypted_channel.txt.bin
-------------- next part --------------
A non-text attachment was scrubbed...
Name: noci_fta_channel.txt.gz
Type: application/x-gzip
Size: 1696 bytes
Desc: not available
Url : http://www.linuxtv.org/pipermail/linux-dvb/attachments/20070520/af4cfff9/noci_fta_channel.txt.bin
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ci_encrypted_channel2.txt.gz
Type: application/x-gzip
Size: 1683 bytes
Desc: not available
Url : http://www.linuxtv.org/pipermail/linux-dvb/attachments/20070520/af4cfff9/ci_encrypted_channel2.txt.bin
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ci_fta_channel.txt.gz
Type: application/x-gzip
Size: 1630 bytes
Desc: not available
Url : http://www.linuxtv.org/pipermail/linux-dvb/attachments/20070520/af4cfff9/ci_fta_channel.txt.bin
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ci_fta_channel_ci_not_initialised.txt.gz
Type: application/x-gzip
Size: 1694 bytes
Desc: not available
Url : http://www.linuxtv.org/pipermail/linux-dvb/attachments/20070520/af4cfff9/ci_fta_channel_ci_not_initialised.txt.bin

More information about the linux-dvb mailing list