snake6502/src/levelreset.asm

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2020-04-08 08:54:54 +00:00
; Reset variables for a new level
; ----------------------------------------------------------------------
2020-04-08 08:54:54 +00:00
levelresetvar:
; Turn MultiColor mode on
jsr multicolorOn
; Init game variables
lda #4
sta irqn ; Initialize interrupt divider
lda #6
sta direction ; Snake must go right
; Note: these values depends on following list initialization
lda #19
sta snakeX ; Snake is at screen center width...
lda #12
sta snakeY ; ... and height
lda #5
sta listStart ; Beginning of snake tiles list
lda #5
sta length ; Length of the list
; Clear snake lists X and Y
ldx #$00
clearListLoop:
dex
lda #19
sta listX,x
lda #12
sta listY,x
cpx #$00
bne clearListLoop
rts