Re: [stella] Crazy Balloon Beginner Mode

Subject: Re: [stella] Crazy Balloon Beginner Mode
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
Date: Tue, 14 Jun 2005 11:05:20 -0400
> I took a look at your source code and noticed something unusual.
> In this code:
>     CLC
>     STA balloonPtr2
>     LDA balloonOffset
>     CLC
>     ADC balloonMoveTab,Y
>     STA balloonmovPtr
>     CLC
>     STA balloonmovPtr2
> Shouldn't BALLOON_HEIGHT be immediate in both cases?  Just a guess.

That seems to be the problem. BALLOON_HEIGHT is defined as 11,
so using it as a zeropage address would read from INPT3. With
no paddle connected this register should still return 11, so
normally the above routine should work as if the values were
immediate. But as it seems z26 reaches the maximum paddle charge
counter value after about 10 minutes even when it emulates
joysticks. (I have to check why this happens.) So after that time
reading from INPT3 will return $8b. This is what causes the strange
look of the balloon. You can get the same thing to happen, if you
press the 'v' key. It simulates a booster grip button, which is
also read through INPT3.

Ciao, Eckhard Stolberg

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