Reply To: sampling phase auto-sync

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The phase seems to jump (180 degrees?) in the optimized modes with every few changes in values. I read another post about PLLDIV2 bug related to the sampling phase. The tvp7002 documentation says half of the sampling phase values are not valid with post divider, but that’s all it says about it. Maybe it isn’t known which settings are invalid until a relationship has been established.

I tried a few things:
– Automatically advancing +1 and then back to +0 of the current phase stting after sync is established. Also tried +2 and +16.
– Button to do the same as above.
– Reset to divide by 1 and then back to divide by 2 after sync is established.
– Re-use the line buffer to record values from a specific row on multiple frames and diff them to measure quality of image.

The button was the only thing that really worked, but it was not reliable. Sometimes it didn’t work on the first press. Resetting the video source, resetting the ossc, or advancing/returning the phase all seem to randomly cause it to get a bad phase after sync. Whether the phase is bad or not seems to correlate with a desync. It consistently goes either in or out of phase every time the red LED lights up when cycling through the phases using the menu. But after power cycling one of the devices it could be either in or out of phase.

I don’t understand the relationship between phase selection and PLLDIV2 well enough to know what else to try.