Zzap

  .inesprg 1   ; 1x 16KB PRG code
  .ineschr 1   ; 1x  8KB CHR data
  .inesmap 0   ; mapper 0 = NROM, no bank swapping
  .inesmir 1   ; background mirroring


;;;;;;;;;;;;;;;

  .org $0000
AddrLow:  .rs 1
AddrHigh:  .rs 1

  .bank 0

  .org $C000
RESET:
  SEI          ; disable IRQs
  CLD          ; disable decimal mode
  LDX #$40
  STX $4017    ; disable APU frame IRQ
  LDX #$FF
  TXS          ; Set up stack
  INX          ; now X = 0
  STX $2000    ; disable NMI
  STX $2001    ; disable rendering
  STX $4010    ; disable DMC IRQs

vblankwait1:       ; First wait for vblank to make sure PPU is ready
  BIT $2002
  BPL vblankwait1

clrmem:
  LDA #$00
  STA $0000, x
  STA $0100, x
  STA $0300, x
  STA $0400, x
  STA $0500, x
  STA $0600, x
  STA $0700, x
  LDA #$FE
  STA $0200, x
  INX
  BNE clrmem

vblankwait2:      ; Second wait for vblank, PPU is ready after this
  BIT $2002
  BPL vblankwait2


LoadPalettes:
  LDA $2002             ; read PPU status to reset the high/low latch
  LDA #$3F
  STA $2006             ; write the high byte of $3F00 address
  LDA #$00
  STA $2006             ; write the low byte of $3F00 address
  LDX #$00              ; start out at 0
LoadPalettesLoop:
  LDA palette, x        ; load data from address (palette + the value in x)
                          ; 1st time through loop it will load palette+0
                          ; 2nd time through loop it will load palette+1
                          ; 3rd time through loop it will load palette+2
                          ; etc
  STA $2007             ; write to PPU
  INX                   ; X = X + 1
  CPX #$20              ; Compare X to hex $10, decimal 16 - copying 16 bytes = 4 sprites<- lol wut? It's CPXing to $20, but says $10. �\(�_O)/�
  BNE LoadPalettesLoop  ; Branch to LoadPalettesLoop if compare was Not Equal to zero
                        ; if compare was equal to 32, keep going down



LoadSprites:
  LDX #$00              ; start at 0
LoadSpritesLoop:
  LDA sprites, x        ; load data from address (sprites +  x)
  STA $0200, x          ; store into RAM address ($0200 + x)
  INX                   ; X = X + 1
  CPX #$10              ; Compare X to hex $10, decimal 16
  BNE LoadSpritesLoop   ; Branch to LoadSpritesLoop if compare was Not Equal to zero
                        ; if compare was equal to 16, keep going down


  LDA $2002
  LDA #$20
  STA $2006             ; write the high byte of $2000 address
  LDA #$00
  STA $2006             ; write the low byte of $2000 address

  LDA #low(background)
  STA AddrLow
  LDA #high(background)
  STA AddrHigh

  LDX #$04              ; Loop X 4 times
  LDY #$00              ; Loop Y 256 times
LoadBackgroundsLoop:
  LDA [AddrLow],y
  STA $2007
  INY
  BNE LoadBackgroundsLoop
; Outer loop
  INC AddrHigh           ; increment high byte of address backg to next 256 byte chunk
  DEX                    ; one chunk done so X = X - 1.
  BNE LoadBackgroundsLoop   ; if X isn't zero, do again


  LDA $2002              ; Reset Scroll
  LDA #$00
  STA $2005
  STA $2005
  STA $2006
  STA $2006


  LDA #%10010000   ; enable NMI, sprites from Pattern Table 0, background from Pattern Table 1
  STA $2000

  LDA #%00011110   ; enable sprites, enable background, no clipping on left side
  STA $2001

Forever:
  JMP Forever     ;jump back to Forever, infinite loop



NMI:
  LDA #$00
  STA $2003       ; set the low byte (00) of the RAM address
  LDA #$02
  STA $4014       ; set the high byte (02) of the RAM address, start the transfer


LatchController:
  LDA #$01
  STA $4016
  LDA #$00
  STA $4016     ;  tell both the controllers to latch buttons

ButtonA:
  LDA $4016       ; player 1 - A
  AND #%00000001  ; look only at bit 0
  BNE ButtonB

; Button stuff here

ButtonB:
  LDA $4016       ; player 1 - B
  AND #%00000001  ; look only at bit 0
  BNE SelectButton

; Button stuff here

SelectButton:
  LDA $4016       ; player 1 - Select
  AND #%00000001  ; look only at bit 0
  BNE StartButton

; Button stuff here

StartButton:
  LDA $4016       ; player 1 - Start
  AND #%00000001  ; look only at bit 0
  BNE UpButton

; Button stuff here

UpButton:
  LDA $4016       ; player 1 - Up
  AND #%00000001  ; look only at bit 0
  BNE DownButton
  LDA $0200       ; load sprite Y position
  CLC             ; make sure the carry flag is clear
  ADC #$01        ; A = A + 1
  STA $0200       ; save sprite Y position
  LDA $0204       ; load sprite Y position
  CLC             ; make sure the carry flag is clear
  ADC #$01        ; A = A + 1
  STA $0204       ; save sprite Y position
  LDA $0208       ; load sprite Y position
  CLC             ; make sure the carry flag is clear
  ADC #$01        ; A = A + 1
  STA $0208       ; save sprite Y position
  LDA $020C       ; load sprite Y position
  CLC             ; make sure the carry flag is clear
  ADC #$01        ; A = A + 1
  STA $020C       ; save sprite Y position

DownButton:
  LDA $4016       ; player 1 - Down
  AND #%00000001  ; look only at bit 0
  BNE LeftButton
  LDA $0200       ; load sprite Y position
  SEC             ; make sure carry flag is set
  SBC #$01        ; A = A - 1
  STA $0200       ; save sprite Y position
  LDA $0204       ; load sprite Y position
  SEC             ; make sure carry flag is set
  SBC #$01        ; A = A - 1
  STA $0204       ; save sprite Y position
  LDA $0208       ; load sprite Y position
  SEC             ; make sure carry flag is set
  SBC #$01        ; A = A - 1
  STA $0208       ; save sprite Y position
  LDA $020C       ; load sprite Y position
  SEC             ; make sure carry flag is set
  SBC #$01        ; A = A - 1
  STA $020C       ; save sprite Y position

LeftButton:
  LDA $4016       ; player 1 - Left
  AND #%00000001  ; look only at bit 0
  BNE RightButton
  LDA $0203       ; load sprite X position
  CLC             ; make sure the carry flag is clear
  ADC #$01        ; A = A + 1
  STA $0203       ; save sprite X position
  LDA $0207       ; load sprite X position
  CLC             ; make sure the carry flag is clear
  ADC #$01        ; A = A + 1
  STA $0207       ; save sprite X position
  LDA $020B       ; load sprite X position
  CLC             ; make sure the carry flag is clear
  ADC #$01        ; A = A + 1
  STA $020B       ; save sprite X position
  LDA $020F       ; load sprite X position
  CLC             ; make sure the carry flag is clear
  ADC #$01        ; A = A + 1
  STA $020F       ; save sprite X position

RightButton:
  LDA $4016       ; player 1 - Right
  AND #%00000001  ; look only at bit 0
  BNE NotRightButton
  LDA $0203       ; load sprite X position
  SEC             ; make sure carry flag is set
  SBC #$01        ; A = A - 1
  STA $0203       ; save sprite X position
  LDA $0207       ; load sprite X position
  SEC             ; make sure carry flag is set
  SBC #$01        ; A = A - 1
  STA $0207       ; save sprite X position
  LDA $020B       ; load sprite X position
  SEC             ; make sure carry flag is set
  SBC #$01        ; A = A - 1
  STA $020B       ; save sprite X position
  LDA $020F       ; load sprite X position
  SEC             ; make sure carry flag is set
  SBC #$01        ; A = A - 1
  STA $020F       ; save sprite X position

NotRightButton:
  JMP ButtonA

  RTI             ; return from interrupt

;;;;;;;;;;;;;;



  .bank 1
  .org $E000
palette:
  .db $22,$29,$1A,$0F,  $22,$36,$17,$0F,  $22,$30,$21,$0F,  $22,$27,$17,$0F   ;;background palette
  .db $22,$12,$36,$15,  $22,$02,$38,$3C,  $22,$1C,$15,$14,  $22,$02,$38,$3C   ;;sprite palette

sprites:
     ;vert tile attr horiz
  .db $80, $32, $00, $80   ;sprite 0
  .db $80, $33, $00, $88   ;sprite 1
  .db $88, $34, $00, $80   ;sprite 2
  .db $88, $35, $00, $88   ;sprite 3


background:
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 2
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$36,$37,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 2
  .db $24,$24,$24,$24,$24,$24,$24,$35,$25,$25,$38,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$45,$45,$24,$24,$45,$45,$45,$45,$45,$45,$24,$24  ;;row 3
  .db $24,$24,$24,$24,$24,$24,$24,$39,$3A,$3B,$3C,$24,$53,$54,$24,$24  ;;some brick tops

  .db $24,$24,$24,$24,$47,$47,$24,$24,$47,$47,$47,$47,$47,$47,$24,$24  ;;row 4
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$55,$56,$24,$24  ;;brick bottoms

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 2
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 2
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$36,$37,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 2
  .db $24,$24,$24,$24,$24,$24,$24,$35,$25,$25,$38,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$45,$45,$24,$24,$45,$45,$45,$45,$45,$45,$24,$24  ;;row 3
  .db $24,$24,$24,$24,$24,$24,$24,$39,$3A,$3B,$3C,$24,$53,$54,$24,$24  ;;some brick tops

  .db $24,$24,$24,$24,$47,$47,$24,$24,$47,$47,$47,$47,$47,$47,$24,$24  ;;row 4
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$55,$56,$24,$24  ;;brick bottoms

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 2
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;row 1
  .db $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24  ;;all sky

attribute:
  .db %00000000, %00000000, %00000000, %00000000, %00000000, %00000000, %00000000, %00000000
  .db %00000000, %00000000, %00000000, %00000000, %00000000, %00000000, %00000000, %00000000
  .db %00000000, %00000000, %00000000, %00000000, %00000000, %10000000, %10100000, %00000000
  .db %00000000, %00000001, %00000101, %00000001, %00000000, %00001000, %00001010, %00000011

  .db %00000000, %00000000, %00000000, %00000000, %00000000, %00000000, %00000000, %00000000
  .db %00000000, %00000000, %00000000, %00000000, %00000000, %00000000, %00000000, %00000000
  .db %00000000, %00000000, %00000000, %00000000, %00000000, %10000000, %10100000, %00000000
  .db %00000000, %00000001, %00000101, %00000001, %00000000, %00001000, %00001010, %00000011



  .org $FFFA     ;first of the three vectors starts here
  .dw NMI        ;when an NMI happens (once per frame if enabled) the
                   ;processor will jump to the label NMI:
  .dw RESET      ;when the processor first turns on or is reset, it will jump
                   ;to the label RESET:
  .dw 0          ;external interrupt IRQ is not used in this tutorial


;;;;;;;;;;;;;;


  .bank 2
  .org $0000
  .incbin "mario.chr"   ;includes 8KB graphics file from SMB1