Re: OMAP3 ISP & BT656

[Gary Thomas <gary@mlbassoc.com>]

On 2012-01-17 14:50, Gary Thomas wrote:
> I have a number of boards with OMAP 3530/3730 that use the
> TVP5150AM1 video decoder. On most of these boards, I can
> capture reasonable quality video. However, I have some (more
> than a few which is reason for concern) where the video is
> either really bad or even the ISP doesn't seem to recognize
> the BT656 data stream. On the ones that have "bad" video,
> the data is all blown out and barely recognizable.
>
> All the boards are running the same kernel (3.0+ with the
> YUV patches that Lennart and others proposed late last year).
> I've verified that the component registers (ISPCCDC and TVP5150)
> match. I can't see what could be the cause of such radically
> variable behaviour.

Sorry, attribution should be to Laurent Pinchart :-)

>
> The one thing I've found is on the boards that don't work
> at all, the CCDC_SYN_MODE[FLDSTAT] bit is not toggling, which
> in turn causes no data to be pushed through the V4L2 pipeline.
>
> Any ideas what can cause this? More importantly, what I can
> try to fix it? The really scary thing is that all the boards
> in my lab work great, but in the factory (some 6000 miles away),
> more than not don't work :-(
>
> Would it be possible to configure the CCDC to capture the
> raw BT656 data? These boards are very small and it's impossible
> to get onto the video data lines going into the processor (they
> are all hidden within the circuit board).
>
> Any help/ideas gladly accepted.
>

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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