Re: [stella] Timing blues...

Subject: Re: [stella] Timing blues...
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
Date: Mon, 30 Jul 2001 18:56:59 +0200
> If the second clock is to clock the pixels out at a different frequency
> the PAL vs NTSC it would be interesting to know the difference in pixel
> frequency.  Which is faster, PAL or NTSC?  Because the difference in
> Kool-Aide working or not working is a bizarre difference that probably has
> nothing to do with color generation.  It is more like a timing glitch.  I
> would not be surprised if the guts of the positioning logic are identical
> between the two machines but the difference in horizontal clock speed is
> what makes the difference.
> But regardless of what the difference turns out to be it would be nice to
> understand what is going on.

OK, I looked up television in the encyclopedia. It seems that the
4.433618 clock corresponds with the carrier frequency for the
colour encoding on PAL systems. The 3.546894 clock corresponds
with the PAL colour burst signal. The colour burst signal on NTSC
seems to be a little higher at about 3.57 MHz, so I'm assuming
that the NTSC VCS is running at that speed? So it seems that the
PAL VCS is a little slower than the NTSC VCS.  How this can cause
effects like in Kool Aide Man I don't know either.

Ciao, Eckhard Stolberg

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