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MOre notes and experimentation

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greg 2016-12-04 16:49:45 -08:00
parent a5c3313651
commit 802c9ff499
1 changed files with 21 additions and 12 deletions
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33
tic_tac.asm
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@ -87,7 +87,7 @@ sta $420b ;start DMA
lda #%10000000 ; VRAM writing mode lda #%10000000 ; VRAM writing mode
sta $2115 sta $2115
ldx #$4000 ldx #$5000
stx $2116 ; write to VRAM stx $2116 ; write to VRAM
;ugly code starts here - it writes the # shape I mentioned before. ;ugly code starts here - it writes the # shape I mentioned before.
@ -144,11 +144,15 @@ stx $2118 ;data for VRAM write register
lda #%00110000 ; 16x16 tiles, mode 0 lda #%00110000 ; 16x16 tiles, mode 0
sta $2105 ; $2105 is the mode for bg mode + tile size sta $2105 ; $2105 is the mode for bg mode + tile size
lda #%01000000 ; data starts from $4000 lda #$50 ; data starts from $4000
sta $2107 ; for bg1 sta $2107 ; for bg1 ; $2107 is address of tile map location for BG1
; tile map location registers:
; %aaaaaass
; a's <- tile map address location, << 11
; ss <- 32x32, 32x64, 32x64, 64x64
lda #%0110000 ; and $6000 lda #60 ; and $6000
sta $2108 ; for bg2 sta $2108 ; for bg2 ; and $2108 is tile map location for BG2
stz $210b ; BG1 and BG2 use the $0000 tiles stz $210b ; BG1 and BG2 use the $0000 tiles
@ -176,19 +180,24 @@ sta $2100
lda #%10000001 ; enable NMI and joypads lda #%10000001 ; enable NMI and joypads
sta $4200 sta $4200
Spin_Loop lda #%00011111
lda #%00000011
sta $2100 sta $2100
mainloop: mainloop:
Spin_Loop Spin_Loop
lda #%00000011 ;lda #%00000011
sta $2100 ;sta $2100
lda #%00110000
sta $2105
Spin_Loop Spin_Loop
lda #$0f
sta $2100 ;lda #$0f
;sta $2100
lda #%00000000
sta $2105
jmp mainloop jmp mainloop