I'm wondering about the SoG and YPrPb thing. In SoG mode with NeoYume the sync is definitely working as I have a stable image. It appears that red and blue colour channels are present in the image where expected, but there's just no green channel video on screen, and what is meant to be white is coming out purple (red+blue), instead of red+blue+green. I still wonder if the levels are setup right or if this thing expects negative 0.3V on green for sync and the different P2 DAC offsets are messing it up. Perhaps the DC restoration during the horizontal blanking intervals is not doing the correct thing to setup the DC levels...? The ADC's are AC coupled on each channel so I would have thought they can work independently but who knows. It could also potentially require i2c access to fully enable SoG perhaps via registers, although I'd imagine it should be possible to detect automatically - and it's already dealing with the lack of sync on H&V on its own too.
I also probed the input impedance of the SOG pin when unpowered and its like 28 mega-ohms, same as each video input. I guess I could probe it with a scope to see if anything is pulling down the green signal on the ADC side while running..?
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Interesting that font is readable, but the character sprites suffer from the classic "uneven eyes" syndrome.
I'm wondering about the SoG and YPrPb thing. In SoG mode with NeoYume the sync is definitely working as I have a stable image. It appears that red and blue colour channels are present in the image where expected, but there's just no green channel video on screen, and what is meant to be white is coming out purple (red+blue), instead of red+blue+green. I still wonder if the levels are setup right or if this thing expects negative 0.3V on green for sync and the different P2 DAC offsets are messing it up. Perhaps the DC restoration during the horizontal blanking intervals is not doing the correct thing to setup the DC levels...? The ADC's are AC coupled on each channel so I would have thought they can work independently but who knows. It could also potentially require i2c access to fully enable SoG perhaps via registers, although I'd imagine it should be possible to detect automatically - and it's already dealing with the lack of sync on H&V on its own too.
I also probed the input impedance of the SOG pin when unpowered and its like 28 mega-ohms, same as each video input. I guess I could probe it with a scope to see if anything is pulling down the green signal on the ADC side while running..?