Do you have any applications notes explaining the use of ADV7343 in non-standard timing mode?
Attached is an apps note with some information on this feature on the old ADV732x. It is however valid for ADV734x encoders
In addition, find a script which was used to configure the encoder for an VGA 640x480 input stream supplied in the form of 8-bit 444 YCbCr data. Customer can use it as a starting point
56 17 02 ; Software Reset
56 00 FC ; Power up all DACs and PLL
56 01 70 ; SELECT INPUT MODE
56 02 10 ; RGB out, sync on all RGB channels
56 30 20 ; ED-HD Nonstandard Timing Mode, Use external HSYNC and VSYNC inputs
56 31 01 ; ED-HD DATA VALID
56 33 2C ; ED-HD MODE REG 4
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