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Pengwin

Addressing modes help needed

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I have this piece of code:

 

; Routine to load the next level
level_vec .word $0000
scrn_vec .word GameScreen + $28
outchar  .byte $00
loadlevel inc level   ;Increment the level
  lda #$05   ;If the level is now 5, then set it back to 1
  cmp level
  beq levelok
  lda #$01
  sta level
levelok  ldx level	 ;Load the level and reduce it by 1
  dex level
  txa	 ;Multiply the level by 2 for the offset
  asl
  tax
  lda lvlvectors,x ;Get the address of the level data
  sta level_vec
  lda lvlvectors+1,x
  sta level_vec+1
  ldy #$00
getscrnchr lda (level_vec),y   ; <---- THIS LINE HERE GENERATES THE ERROR
  cmp #$FF
  beq leveldone
  tax
  and #$0f
  clc
  adc #$40
  sta outchar
  txa
  lsr
  lsr
  lsr
  lsr
  tax
  lda outchar
rptscrnchr cpx #$00
  beq getscrnchr
  sta (level_vec),y
  iny
  dex
  jmp rptscrnchr
 
  ;  ++++++ HERE ++++++
leveldone lda #$00   ;Temporary instruction
  rts

 

I know it's probablu quite messy, but this is my first real assembly project.

However, when I try to run the assembler, it tells me that I have an illegal addressing mode on the indicated line. I though that indirect-indexed was allowed for LDA.

 

Any help please

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Never mind, just found out that it is for zero-page addresses only. That will explain my error

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