ADV7188 - what are the register settings to add graphics to NTSC blue screen?
You mean the overlay functionality? I don't no that it works with no CVBS input. You'd have to use the FB pin if it did though-- no register setting for that since you couldn't alpha blend with no CVBS input signal to key off. The different overlay modes are on page 16/17 of the data sheet.
No, this is just for background information, not using overlay functionality of the ADV7188. Need is to configure the ADV7188 to output a blue screen (as in free-run mode) in ITU656 NTSC format, provided that there is no analog input to the ADV7188.
If there is no lock, it'll free-run by default with a blue screen. You can check bit 4 of register 0x13 to check if it's free-running. It's not clear from the docs but I think you can use VID_SEL to set the free run output timing.
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