Re: [stella] Qb/Demo background animation (playable)

Subject: Re: [stella] Qb/Demo background animation (playable)
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
Date: Wed, 7 Feb 2001 22:06:51 +0100
> This version, you complete the level, it goes onto the next one.  No
> code this time.  I just have to do the creatures AI, fixup the jitters, do
> some scoring and sounds... and I'll be done.  Then I want to release a

Judging by the source code for the last version, the jittering
problem comes from the INTIM loops for vblank and overscan. In
the vblank loop you should change the BMI for a BNE. INTIM returns
the current timer value, and if you set it up with a value of 42,
then the BMI will fail and the loop will never be taken.

For the overscan you need to set up a TIM64 timer for 30 scanlines
and add a deley loop after you have called all subroutines. Then
you will be able to generate the same number of scanlines regardless
of how long the subroutines take to execute.

BTW maybe you could have a look at the joystick routines too.
At least on z26 the game feels a little unsmooth.

> cart... DESPITE the lack of interest ;)  So, will ANYONE buy this on cart,
> numbered and signed??

On RGVC someone managed to sell a game that he didn't even had
written yet. Since you already have a working demo, your chances
should be even better. ;-)

Ciao, Eckhard Stolberg

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