INCLUDE "hardware.inc" ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; Header section ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ SECTION "Header", ROM0[$100] jp EntryPoint ds $150 - @, 0 ; Make room for the header! ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; Initialization section ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ EntryPoint: ; Do not turn the LCD off outside of VBlank WaitVBlank1: ld a, [rLY] ; Load our LCD Y position into a cp 144 ; Compare to 144 jp c, WaitVBlank1; Jump if carry (if a < 144) ; Turn the LCD off ld a, 0 ; Load 0's into a ld [rLCDC], a ; Set our LCD Controller to 0 to turn everything off ;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; V RAM operations ;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; Copy the background tile data ld de, bgTileStart ; Load our tile block start into d/e ld hl, $9000 ; Load our VRAM start into h/l ld bc, bgTileEnd - bgTileStart ; Load the size of our tile block into b/c Memcopy1: ld a, [de] ; Load value from source into a. ld [hli], a ; Load that value into destination and increment destination pointer. inc de ; Increment our source pointer. dec bc ; Decrement our length value ld a, b ; Load the value of b into a or a, c ; Or a with c jp nz, Memcopy1 ; While a and c are nonzero, jump back to Memcopy ; Copy the background tilemap data ld de, bgMapStart ; Load our tilemap block start into d/e ld hl, $9800 ; Load our VRAM start into h/l ld bc, bgMapEnd - bgMapStart ; Load the size of our tilemap block into b/c Memcopy2: ld a, [de] ; Load value from source into a. ld [hli], a ; Load that value into destination and increment destination pointer. inc de ; Increment our source pointer. dec bc ; Decrement our length value ld a, b ; Load the value of b into a or a, c ; Or a with c jp nz, Memcopy2 ; While a and c are nonzero, jump back to Memcopy ;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; OAM RAM operations ;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; Startup ;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; Turn the LCD on ld a, LCDCF_ON | LCDCF_BGON ; Pretty clear what this does, actually. ld [rLCDC], a ; LCDCF_ON and LDCDF_BGON are the bits that control the LCD and background ; During the first (blank) frame, initialize display registers ld a, %00011011 ; rBGP = FF47. Palettes: ID 0:white 1:LG 2:DG 3:Black ld [rBGP], a ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; Main program loop ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Main: ; Wait until it's *not* VBLANK ld a, [rLY] ; Load our LCD Y position into a cp 144 ; Compare it to 144 jp nc, Main ; Jump if carry (a < 144) WaitVBlank2: ; Wait until it *is* VBLANK ld a,[rLY] cp 144 jp c, WaitVBlank2 jp Main ; Loop infinitely ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; Functions ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; Tile data ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ SECTION "Tile data", ROM0 bgTileStart: db %11111111, %11111111 db %11111111, %11111111 db %11111111, %11111111 db %11111111, %11111111 db %11111111, %11111111 db %11111111, %11111111 db %11111111, %11111111 db %11111111, %11111111 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10011001, %11100111 db %11000011, %11111111 db %11111111, %11111111 db %11111111, %11111111 db %11000000, %11111111 db %10011111, %11100000 db %10100000, %11000000 db %10100000, %11000000 db %10011111, %11100000 db %11000000, %11111111 db %11111111, %11111111 db %10100100, %11000011 db %10100010, %11000001 db %10010001, %11100000 db %11001000, %11110000 db %11100100, %11111000 db %11110011, %11111100 db %11111000, %11111111 db %11111111, %11111111 db %11111111, %11111111 db %11000011, %11111111 db %10011001, %11100111 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %10100101, %11000011 db %11111111, %11111111 db %11111000, %11111111 db %11110011, %11111100 db %11100100, %11111000 db %11001000, %11110000 db %10010001, %11100000 db %10100010, %11000001 db %10100100, %11000011 db %10100100, %11000011 db %10100010, %11000001 db %10010001, %11100000 db %11001000, %11110000 db %11001000, %11110000 db %10010001, %11100000 db %10100010, %11000001 db %10100100, %11000011 db %11111111, %11111111 db %00000011, %11111111 db %11111001, %00000111 db %00000101, %00000011 db %00000101, %00000011 db %11111001, %00000111 db %00000011, %11111111 db %11111111, %11111111 db %00100101, %11000011 db %01000101, %10000011 db %10001001, %00000111 db %00010011, %00001111 db %00100111, %00011111 db %11001111, %00111111 db %00011111, %11111111 db %11111111, %11111111 db %11111111, %11111111 db %00000000, %11111111 db %11111111, %00000000 db %00000000, %00000000 db %00000000, %00000000 db %11111111, %00000000 db %00000000, %11111111 db %11111111, %11111111 db %00100100, %11000011 db %01000010, %10000001 db %10000001, %00000000 db %00011000, %00000000 db %00100100, %00011000 db %11000011, %00111100 db %00011000, %11111111 db %11111111, %11111111 db %11111111, %11111111 db %00011111, %11111111 db %11001111, %00111111 db %00100111, %00011111 db %00010011, %00001111 db %10001001, %00000111 db %01000101, %10000011 db %00100101, %11000011 db %00100101, %11000011 db %01000101, %10000011 db %10001001, %00000111 db %00010011, %00001111 db %00010011, %00001111 db %10001001, %00000111 db %01000101, %10000011 db %00100101, %11000011 db %11111111, %11111111 db %00011000, %11111111 db %11000011, %00111100 db %00100100, %00011000 db %00011000, %00000000 db %10000001, %00000000 db %01000010, %10000001 db %00100100, %11000011 db %00100100, %11000011 db %01000010, %10000001 db %10000001, %00000000 db %00011000, %00000000 db %00011000, %00000000 db %10000001, %00000000 db %01000010, %10000001 db %00100100, %11000011 bgTileEnd: bgMapStart: db $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$04,$00,$04,$06,$0A,$08,$04,$00,$00,$04,$00,$00,$06,$0A,$0C,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$05,$00,$05,$05,$00,$00,$05,$00,$00,$05,$00,$00,$05,$00,$05,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$07,$0A,$0D,$07,$0A,$08,$05,$00,$00,$05,$00,$00,$05,$00,$05,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$05,$00,$05,$05,$00,$00,$05,$00,$00,$05,$00,$00,$05,$00,$05,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$01,$00,$01,$03,$0A,$08,$03,$0A,$08,$03,$0A,$08,$03,$0A,$09,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$04,$04,$04,$06,$0A,$0C,$06,$0A,$0C,$04,$00,$00,$06,$0C,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$05,$05,$05,$05,$00,$05,$05,$00,$05,$05,$00,$00,$05,$03,$0C,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$05,$05,$05,$05,$00,$05,$07,$0E,$09,$05,$00,$00,$05,$00,$05,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$05,$05,$05,$05,$00,$05,$05,$03,$0C,$05,$00,$00,$05,$06,$09,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$03,$0B,$09,$03,$0A,$09,$01,$00,$01,$03,$0A,$08,$03,$09,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 db $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00 bgMapEnd: ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ; Global variables ; ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~