[pvrusb2] problem with a hvr-1900

[Mike Isely]

On Fri, 10 Sep 2010, vdb128 at picaros.org wrote:

> > strange, even if it says that root was the owner I coulnt do anything.
> 
> The file redirection ' >/path/to/file' is done by the shell that
> interpretes the command.  You might want to give
> 
>   sudo sh -c 'echo "composite" >/sys/class/pvrusb2/sn*/ctl_input/cur_val'

I think you nailed it.  This is not the first time people have been 
fooled by sudo and file redirection!

> 
> a try.  Make sure there is a valid composite signal.  Then try
> 
>   dd if=/dev/video0 of=test.mpg bs=4096 count=1000
> 
> which should take less than 10 seconds.  If the file does play, 
> e.g. mplayer outputs
> 
> A:   0.2 V:   0.3 A-V: -0.138 ct:  0.000   2/  2 ??% ??% ??,?% 0 0 
> Broken frame at 0x236A0                                                  
> A:   3.5 V:   3.8 A-V: -0.327 ct: -0.285  90/ 90 11%  4%  0.6% 0 0 
> 
> but contains a black image then the signal doesn't reach the working 
> encoder chip.  Support for the last variant of the hvr-1900 is very 
> recent.  You may need to upgrade to linux 2.6.35.4.

Another thing that is very useful to try when suspecting RF tuner 
problems: bypass the tuner.

If you attempt a capture using the s-video or composite inputs (like the 
detailed sequence I had told Lorne about which he then forwarded to the 
list), then you're testing every aspect of the video pipeline *except* 
the RF tuner.  So if such an experiment succeeds, then you know 
everything else is healthy.

  -Mike

-- 

Mike Isely
isely @ isely (dot) net
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