I'm trying to get a consistent 480p video input working with the ADV7619. The problem I'm having is the recommended value for IO register 0x05 (i2c address 0x98) is 0x28. However, if I am showing 720p double pixel mode and then want to switch to 480p single pixel per clock mode, as the last step, I have to write 0x08 to this register. This zero's out bit 0x20 (a bit right next to F_OUT_SEL). This bit appears undocumented, but I'm not sure why this works.
In fact, if the bit is left a zero instead of the default of 1, then everything seems to work fine.
Is this causing a problem? Or, is there more documentation on this bit?