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|
.segment "CODE"
;; Check `basics/sprite.s` for a deeper look on the logic below. I have only
;; added code after configuration/reset is done.
.proc reset
sei
cld
ldx #$40
stx $4017
ldx #$FF
txs
inx
stx $2000
stx $2001
stx $4010
bit $2002
@vblankwait1:
bit $2002
bpl @vblankwait1
ldx #0
lda #0
@ram_reset_loop:
sta $000, x
sta $100, x
sta $300, x
sta $400, x
sta $500, x
sta $600, x
sta $700, x
inx
bne @ram_reset_loop
lda #$EF
@sprite_reset_loop:
sta $200, x
inx
bne @sprite_reset_loop
@vblankwait2:
bit $2002
bpl @vblankwait2
;;;
;; NOTE: configuration/reset is done, the code below is our actual program :D
jmp main
.endproc
|
