Re: [hatari-devel] video freq set to 60 Hz instead of 50 Hz for Falcon VGA

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 28/02/2024 à 09:07, Miro Kropáček a écrit :
> On Wed, 28 Feb 2024 at 09:03, Nicolas Pomarède <npomarede@xxxxxxxxxxxx 
> <mailto:npomarede@xxxxxxxxxxxx>> wrote:
>
>     but then, out of curiosity, why do TOS and Emutos set ff820a when
>     configuring videl video mode ?
>
>     Or maybe ff820a is taken into account in "st compatible mode" when
>     writing the resolution to ff8260 ?
>
> Frankly, I don't know. I wasn't even aware of 820a until this thread. 
> :-) My guess would be they wanted to keep it for backward compatibility, 
> perhaps mainly for the ST modes as you have said.

If you look at the thread "Sync byte on Falcon" here (in sept and nov 
2023), Roger made some tests on his falcon and the content of ff820a is 
modified depending on the video mode.

so indeed, it's not very clear what it's used for :(