Re: [stella] FWD: help with Indirect Indexed Addressing

Subject: Re: [stella] FWD: help with Indirect Indexed Addressing
From: "Andrew Davie" <atari2600@xxxxxxxxxxxxx>
Date: Mon, 8 Sep 2003 13:37:43 +1000
> LDA #00
> ;if the p0VisibleLine is non zero,
> ;we're drawing it
> LDX p0VisibleLine
> BEQ FinishPlayer0 ;we're done drawing
> DEC p0VisibleLine
> LDA (pointerP0Graphic),X ;what's wrong with this???
> ;LDA #%10011001
> FinishPlayer0
> STA p0DrawBuffer



There is no (indirect),x addressing mode!
I'm surprised the assembler is letting you do this, but it's probably
interpreting the statement as an expression with indexed addressing.
Which would come out to basically  just   lda  pointerP0Graphic,x
You can only use the Y register for the addressing mode you're after, here.

Cheers
A


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