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Reset::
di
call InitSound
xor a
ldh [hMapAnims], a
call ClearPalettes
xor a
ldh [rIF], a
ld a, 1 << VBLANK
ldh [rIE], a
ei
ld hl, wcfbe
set 7, [hl]
ld c, 32
call DelayFrames
jr Init
_Start::
cp $11
jr z, .cgb
xor a ; FALSE
jr .load
.cgb
ld a, TRUE
.load
ldh [hCGB], a
ld a, TRUE
ldh [hSystemBooted], a
Init::
di
xor a
ldh [rIF], a
ldh [rIE], a
ldh [rRP], a
ldh [rSCX], a
ldh [rSCY], a
ldh [rSB], a
ldh [rSC], a
ldh [rWX], a
ldh [rWY], a
ldh [rBGP], a
ldh [rOBP0], a
ldh [rOBP1], a
ldh [rTMA], a
ldh [rTAC], a
ld [wd000], a
ld a, %100 ; Start timer at 4096Hz
ldh [rTAC], a
.wait
ldh a, [rLY]
cp LY_VBLANK + 1
jr nz, .wait
xor a
ldh [rLCDC], a
; Clear WRAM bank 0
ld hl, WRAM0_Begin
ld bc, WRAM0_End - WRAM0_Begin
.ByteFill:
ld [hl], 0
inc hl
dec bc
ld a, b
or c
jr nz, .ByteFill
ld sp, wStackTop
; Clear HRAM
ldh a, [hCGB]
push af
ldh a, [hSystemBooted]
push af
xor a
ld hl, HRAM_Begin
ld bc, HRAM_End - HRAM_Begin
call ByteFill
pop af
ldh [hSystemBooted], a
pop af
ldh [hCGB], a
call ClearWRAM
ld a, 1
ldh [rSVBK], a
call ClearVRAM
call ClearSprites
call ClearsScratch
ld a, BANK(WriteOAMDMACodeToHRAM) ; aka BANK(GameInit)
rst Bankswitch
call WriteOAMDMACodeToHRAM
xor a
ldh [hMapAnims], a
ldh [hSCX], a
ldh [hSCY], a
ldh [rJOYP], a
ld a, $8 ; HBlank int enable
ldh [rSTAT], a
ld a, $90
ldh [hWY], a
ldh [rWY], a
ld a, 7
ldh [hWX], a
ldh [rWX], a
ld a, LCDC_DEFAULT ; %11100011
; LCD on
; Win tilemap 1
; Win on
; BG/Win tiledata 0
; BG Tilemap 0
; OBJ 8x8
; OBJ on
; BG on
ldh [rLCDC], a
ld a, CONNECTION_NOT_ESTABLISHED
ldh [hSerialConnectionStatus], a
farcall InitCGBPals
ld a, HIGH(vBGMap1)
ldh [hBGMapAddress + 1], a
xor a ; LOW(vBGMap1)
ldh [hBGMapAddress], a
farcall StartClock
xor a ; SRAM_DISABLE
ld [MBC3LatchClock], a
ld [MBC3SRamEnable], a
ldh a, [hCGB]
and a
jr z, .no_double_speed
call NormalSpeed
.no_double_speed
xor a
ldh [rIF], a
ld a, IE_DEFAULT
ldh [rIE], a
ei
call DelayFrame
predef InitSGBBorder
call InitSound
xor a
ld [wMapMusic], a
jp GameInit
ClearVRAM::
; Wipe VRAM banks 0 and 1
ld a, 1
ldh [rVBK], a
call .clear
xor a ; 0
ldh [rVBK], a
.clear
ld hl, VRAM_Begin
ld bc, VRAM_End - VRAM_Begin
xor a
call ByteFill
ret
ClearWRAM::
; Wipe swappable WRAM banks (1-7)
; Assumes CGB or AGB
ld a, 1
.bank_loop
push af
ldh [rSVBK], a
xor a
ld hl, WRAM1_Begin
ld bc, WRAM1_End - WRAM1_Begin
call ByteFill
pop af
inc a
cp 8
jr nc, .bank_loop ; Should be jr c
ret
ClearsScratch::
; Wipe the first 32 bytes of sScratch
ld a, BANK(sScratch)
call OpenSRAM
ld hl, sScratch
ld bc, $20
xor a
call ByteFill
call CloseSRAM
ret
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