My customer is seeing some issues in the video pipeline. He is trying to figure it out but there are important pieces of information MISSING from the datasheets and user guide for the ADV7282A.
For example, in a post on EZ someone asked about the timing and bt656 format of the progressive video from the ADV7282A. The Analog Devices FAE recommend that the book Video Demystified.
I checked out the book and found the page in question. The VBI in the book are lines 1-44 and line 525.
However, when I sent the bt656 decoded Vsync and Hsync from the ADV7282A to two test points connected to a oscilloscope and I am seeing 18 lines for the Vsync. I am using format 720 x 487 as seen on page 36 Table 72, so I expected to see more lines of vsync.
There also appears to be dropped lines of hsync. I need more data on the bt656 frame format Analog Devices is ACTUALLY using.
I am seeing the ff..00..00..86, ff..00.00.AB, ff..00.00.9D and ff..00.00.80 bt656 codes but lines of video seem to be missing going by the what appears to be dropped hsyncs.
Any idea or answers to what might be going on?
As per expert comment "In 480p mode when BT.656-4 bit equal to 1 the output format is actually 720x507 not 720x 487". There is a mistake in document which will be updating shortly. Please refer here ez.analog.com/.../12106