Split more code out of home.asm.

1 files changed, 139 insertions, 0 deletions

diff --git a/home/init.asm b/home/init.asm
new file mode 100644
index 00000000..939e81b5
--- /dev/null
+++ b/home/init.asm
@@ -0,0 +1,139 @@
+SoftReset::
+	call StopAllSounds
+	call GBPalWhiteOut
+	ld c, $20
+	call DelayFrames
+	; fallthrough
+
+Init::
+;  Program init.
+
+rLCDC_DEFAULT EQU %11100011
+; * LCD enabled
+; * Window tile map at $9C00
+; * Window display enabled
+; * BG and window tile data at $8800
+; * BG tile map at $9800
+; * 8x8 OBJ size
+; * OBJ display enabled
+; * BG display enabled
+
+	di
+
+	xor a
+	ld [rIF], a
+	ld [rIE], a
+	ld [$ff43], a
+	ld [$ff42], a
+	ld [$ff01], a
+	ld [$ff02], a
+	ld [$ff4b], a
+	ld [$ff4a], a
+	ld [$ff06], a
+	ld [$ff07], a
+	ld [$ff47], a
+	ld [$ff48], a
+	ld [$ff49], a
+
+	ld a, rLCDC_ENABLE_MASK
+	ld [rLCDC], a
+	call DisableLCD
+
+	ld sp, wStack
+
+	ld hl, $c000 ; start of WRAM
+	ld bc, $2000 ; size of WRAM
+.loop
+	ld [hl], 0
+	inc hl
+	dec bc
+	ld a, b
+	or c
+	jr nz, .loop
+
+	call ClearVram
+
+	ld hl, $ff80
+	ld bc, $ffff - $ff80
+	call FillMemory
+
+	call ClearSprites
+
+	ld a, Bank(WriteDMACodeToHRAM)
+	ld [H_LOADEDROMBANK], a
+	ld [MBC3RomBank], a
+	call WriteDMACodeToHRAM
+
+	xor a
+	ld [$ffd7], a
+	ld [$ff41], a
+	ld [$ffae], a
+	ld [$ffaf], a
+	ld [$ff0f], a
+	ld a, 1 << VBLANK + 1 << TIMER + 1 << SERIAL
+	ld [rIE], a
+
+	ld a, 144 ; move the window off-screen
+	ld [$ffb0], a
+	ld [rWY], a
+	ld a, 7
+	ld [rWX], a
+
+	ld a, $ff
+	ld [$ffaa], a
+
+	ld h, vBGMap0 / $100
+	call ClearBgMap
+	ld h, vBGMap1 / $100
+	call ClearBgMap
+
+	ld a, rLCDC_DEFAULT
+	ld [rLCDC], a
+	ld a, 16
+	ld [hSoftReset], a
+	call StopAllSounds
+
+	ei
+
+	ld a, $40 ; PREDEF_SGB_BORDER
+	call Predef
+
+	ld a, $1f
+	ld [wc0ef], a
+	ld [wc0f0], a
+	ld a, $9c
+	ld [$ffbd], a
+	xor a
+	ld [$ffbc], a
+	dec a
+	ld [wcfcb], a
+
+	ld a, $32 ; PREDEF_INTRO
+	call Predef
+
+	call DisableLCD
+	call ClearVram
+	call GBPalNormal
+	call ClearSprites
+	ld a, rLCDC_DEFAULT
+	ld [rLCDC], a
+
+	jp SetDefaultNamesBeforeTitlescreen
+
+ClearVram:
+	ld hl, $8000
+	ld bc, $2000
+	xor a
+	jp FillMemory
+
+
+StopAllSounds::
+	ld a, Bank(Func_9876)
+	ld [wc0ef], a
+	ld [wc0f0], a
+	xor a
+	ld [wMusicHeaderPointer], a
+	ld [wc0ee], a
+	ld [wcfca], a
+	dec a
+	jp PlaySound