Re: [stella] Timing blues...

Subject: Re: [stella] Timing blues...
From: "John Saeger" <john@xxxxxxxxxxx>
Date: Sun, 29 Jul 2001 11:15:26 -0700
Chris Wilkson wrote:

> It's true that NTSC decks only have one clock circuit.  Why would you need
> 2 for PAL?  But I remember seeing the 2 generators when I opened up the
> you sent me, and at the time I think I suspected that one was for "normal"
> PAL, and one was for 4.43 NTSC.  But it didn't make sense that they'd
> the components for both circuits.  I don't remember...maybe I'll take
> look before CGE.

If the second clock is to clock the pixels out at a different frequency for
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.

Eckhard Stolberg wrote:

> BTW, did you get my email with the changes to the z26 cpu engine
> and just didn't have time to answer it yet, or was that lost again?

I got them.  They've been released and available for hours.  ;-)  For
everyone else's information, this version (1.46) has better bus state
emulation for better emulation of illegal TIA reads.


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