RE: [stella] why -68?

Subject: RE: [stella] why -68?
From: Nicolás Olhaberry <nolh@xxxxxxxxxxxxx>
Date: Wed, 7 Nov 2001 08:29:50 -0300
----- Original Message -----
From: John Saeger <john@xxxxxxxxxxx>
To: <stella@xxxxxxxxxxx>
Sent: Tuesday, November 06, 2001 1:49 PM
Subject: Re: [stella] why -68?

> In any case, we start counting TIA cycles at -68 because that's how PCAE
> does it.  We wanted to make it easy to compare results between z26 and
> When working on an emu, it's very handy to be able to compare with other
> ones.  But this way TIA starts drawing at cycle 0.

What do you mean by "but"? From my experience looks like HBLANK ends at
colorclock 66 instead of the documented 68. If this is correct. when I
position an object (having it´s delay in consideration)  to be displayed in
colorclock 66, or , let say, 159 (since I´m not too sure about moving
limits), would this two pixels be visible? Mmm... maybe just giving the
background a different color from the playfield would be enough to see this.

Does this make any sense? I guess it´s time to get an atari and a cuttle
cart... ;-)

> ...
.  Funny, even to this
> day we're still having discussions about where a scanline should end and
> next one should begin.  It has to do with the worm war demo that was
> a while back.  In z26 1.51 it doesn't jitter any more.  Some of us think
> should still be jittering, and some of us aren't so sure.  Stay tuned.

I would be very interested in hearing more on that subject...



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