2009-06-10 10:51:01 ADV7183B and BF527 EZKit video capture problems
Stefan Wanja (GERMANY)
Message: 75465
Hello,
I am trying to get the adv7183b daughterboard running with the bf527 EZkit. I am using toolchain and uboot and uclinux-dist with kernel from svn trunk, revision 8255. The ffmpeg libs and binary I'm using is from 2008R1.5. I have proceeded so far, that now I can actually capture video.
But what I capture looks like there is a sync problem. Please see the attached screenshot. This should be numbes 1-12 splitted up in three rows.
I think the black/green vertical bars are line syncs. There also seems to be a frame sync in the middle. When you move all "line syncs" on one line, you get an almost correct image (except for the colour). When watched as a video the syncs are moving around chaotically.
I have a Canon Ixus' TV out (PAL) attached the the AVIN5 of the adv7183b.
Has someone an idea, what the problem could be?
Kind regards,
Stefan
vlcsnap-5381393.png
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2009-06-10 11:07:25 Re: ADV7183B and BF527 EZKit video capture problems
Stefan Wanja (GERMANY)
Message: 75467
additional info:
I disabled PPI_ERROR request in the driver after I got many many PPI_ERROR interrupts (at least 1000x more than PPI DMA interrupts) and changing interrupt priority (as stated in the docs http://docs.blackfin.uclinux.org/doku.php?id=ppi) didn't help.
SysClock is 131,25MHz and core is running at 525MHz.
The PPI_CLK looks ok when looking at with an oscilloscope.
What could cause those PPI_ERRORS and could this lead to the sync problems as in the picture?
Kind regards again,
Stefan
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2009-06-10 11:28:45 Re: ADV7183B and BF527 EZKit video capture problems
Michael Hennerich (GERMANY)
Message: 75469 Are you really sure that your clock is ok?
Did you disable the BF527-EZKIT onboard clock - used for the display???
A PPI ERROR typically signals lost synchronization.
With the ADV7183 in ITU BT656 mode this can happen even if there is only
one glitch in the clock.
-Michael
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2009-06-11 05:32:20 Re: ADV7183B and BF527 EZKit video capture problems
Stefan Wanja (GERMANY)
Message: 75525
Hey Michael,
thanks alot for your reply. I figured it out now. I wrongly used the 27MHz clock signal that goes into the video encoder also as PPI clock and that was obviously not in sync with the encoder's output. After choosing VDEC_CLKOUT as PPI_CLK it works fine.
Thank you!
Stefan
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2009-06-11 07:13:01 Re: ADV7183B and BF527 EZKit video capture problems
Stefan Wanja (GERMANY)
Message: 75531
I meant decoder when I wrote encoder of cause...