Re: Re: [stella] Climber 5 RC#03

Subject: Re: Re: [stella] Climber 5 RC#03
From: Dennis Debro <ddebro@xxxxxxxxxxxxx>
Date: Wed, 11 Feb 2004 7:22:48 -0500
Hi there,

> > LDA affects the N and Z flags, so you can do BMI / BPL as well as  BNE 
> > BEQ, but I have never seen where it affects the carry.
> Hm... because it doesn't change the carry. Did the original code branch 
> according to the carry state?

Yes it did. The original was...

   ldx obstacleType                 ; get the obstacle type
   cpx #$04                         ; see if the obstacle is harmful to the climber
   lda CXPPMM                       ; read the player collisions
   bpl .overscanWait                ; if no collisions then jump to the big wait
   bcs .playerGirderCollision

Either way I like the new one because it reads better.

Take care,

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