Re: Open hardware AV to digital conversion

The problem is that the non interlace and interlace displays have a 
different frame rate because of the extra half scan line per field.

I think the c64 is 59.83hz, but interlaced NTSC frame rate is 59.94hz.

To be perfectly legal the frame rate has to be a multiple of the line 
rate, so I don't see how you can manipulate the output to hit the same 
frame rate using a simple line buffer.

Taking 240p in and outputting 480p (vga, component, dvid or hdmi) is 
likely to be a whole lot easier. You'll still have to deal with 
mismatched frame rates, but you won't have the half lines.

The NES HDMI that kevtris is working on changes the NES clock speed so 
the output is 60hz, which is probably not a good idea on the c64 because 
of 1541 timing.


On 09/01/2015 23:46, silverdr@wfmh.org.pl wrote:
>
> I want the solution to reconstruct the sync pulses itself but what you 
> say has to be double-checked. If you say that I may run out of the 
> VBLANK time to get the proper timing and remain in sync with the 
> source then this would indeed pose a problem, solving which would make 
> the whole thing more difficult. I think, however that this is not the 
> case. 


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