Re: Re: [stella] Help with my demo, PAL, NTSC :-)

Subject: Re: Re: [stella] Help with my demo, PAL, NTSC :-)
From: Dennis Debro <ddebro@xxxxxxxxxxxxx>
Date: Mon, 24 Mar 2003 18:42:55 -0500
> This sounds illogical! My current values: NTSC VBLANK: $01( 1 count X
> TIM64T ), IIRC, this gave my 202 lines. I haven't changed PAL VBLANK yet.
> NTSC overscan: also $01!

So that says your kernel is ~200 scan lines. 

> VBLANK is supposed to be 43 or 44 x TIM64T, right? So my current values
> should cause the screen in z26 to ROLL, right?

That depends. If you're going for a 200 scan line kernel you will have adjust your vertical blank and overscan lines accordingly. For example, Climber 5 has 200 scan lines for the kernel. To stay within the 262 scan lines for an NTSC display I chopped 4 lines off vertical blank and overscan time.

> Does z26 show NTSC 192 lines or does it "display" all 262 lines?

Z26 counts the number of scan lines before the next frame.

I hope this helps you.

Take care,

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