Organize the engine/ directory, take 3

Renamed `title` to `movies`.
Moved some functions from `engine/routines/` to their fitting
directories, and cleaned up the base `engine/` directory.
Moved `engine/pokemon/tmhm.asm` back to `engine/items/`.

Made a new subdirectory:
* engine/tilesets: Contains all map-related graphics routines.

3 files changed, 2734 insertions, 0 deletions

diff --git a/engine/menus/debug.asm b/engine/menus/debug.asm
new file mode 100755
index 000000000..4c3110fe1
--- /dev/null
+++ b/engine/menus/debug.asm
@@ -0,0 +1,1447 @@
+	const_def $6a
+	const DEBUGTEST_UP_ARROW ; $6a
+	const DEBUGTEST_TICKS    ; $6b
+	const DEBUGTEST_WHITE    ; $6c
+	const DEBUGTEST_LIGHT    ; $6d
+	const DEBUGTEST_DARK     ; $6e
+	const DEBUGTEST_BLACK    ; $6f
+	const DEBUGTEST_0        ; $70
+	const DEBUGTEST_1        ; $71
+	const DEBUGTEST_2        ; $72
+	const DEBUGTEST_3        ; $73
+	const DEBUGTEST_4        ; $74
+	const DEBUGTEST_5        ; $75
+	const DEBUGTEST_6        ; $76
+	const DEBUGTEST_7        ; $77
+	const DEBUGTEST_8        ; $78
+	const DEBUGTEST_9        ; $79
+	const DEBUGTEST_A        ; $7a
+	const DEBUGTEST_B        ; $7b
+	const DEBUGTEST_C        ; $7c
+	const DEBUGTEST_D        ; $7d
+	const DEBUGTEST_E        ; $7e
+	const DEBUGTEST_F        ; $7f
+
+ColorTest: ; 818ac
+; A debug menu to test monster and trainer palettes at runtime.
+
+	ld a, [hCGB]
+	and a
+	jr nz, .asm_818b5
+	ld a, [hSGB]
+	and a
+	ret z
+
+.asm_818b5
+	ld a, [hInMenu]
+	push af
+	ld a, $1
+	ld [hInMenu], a
+	call DisableLCD
+	call Function81948
+	call Function8197c
+	call Function819a7
+	call Function818f4
+	call EnableLCD
+	ld de, MUSIC_NONE
+	call PlayMusic
+	xor a
+	ld [wJumptableIndex], a
+	ld [wcf66], a
+	ld [wd003], a
+.asm_818de
+	ld a, [wJumptableIndex]
+	bit 7, a
+	jr nz, .asm_818f0
+	call Function81a74
+	call Function81f5e
+	call DelayFrame
+	jr .asm_818de
+
+.asm_818f0
+	pop af
+	ld [hInMenu], a
+	ret
+; 818f4
+
+Function818f4: ; 818f4
+	ld a, [wd002]
+	and a
+	jr nz, Function81911
+	ld hl, PokemonPalettes
+
+Function818fd: ; 818fd
+	ld de, wOverworldMap
+	ld c, NUM_POKEMON + 1
+.asm_81902
+	push bc
+	push hl
+	call Function81928
+	pop hl
+	ld bc, 8
+	add hl, bc
+	pop bc
+	dec c
+	jr nz, .asm_81902
+	ret
+
+Function81911: ; 81911
+	ld hl, TrainerPalettes
+	ld de, wOverworldMap
+	ld c, NUM_TRAINER_CLASSES
+.asm_81919
+	push bc
+	push hl
+	call Function81928
+	pop hl
+	ld bc, 4
+	add hl, bc
+	pop bc
+	dec c
+	jr nz, .asm_81919
+	ret
+; 81928
+
+Function81928: ; 81928
+	ld a, BANK(PokemonPalettes) ; BANK(TrainerPalettes)
+	call GetFarByte
+	ld [de], a
+	inc de
+	inc hl
+	ld a, BANK(PokemonPalettes) ; BANK(TrainerPalettes)
+	call GetFarByte
+	ld [de], a
+	inc de
+	inc hl
+	ld a, BANK(PokemonPalettes) ; BANK(TrainerPalettes)
+	call GetFarByte
+	ld [de], a
+	inc de
+	inc hl
+	ld a, BANK(PokemonPalettes) ; BANK(TrainerPalettes)
+	call GetFarByte
+	ld [de], a
+	inc de
+	ret
+; 81948
+
+Function81948: ; 81948
+	ld a, $1
+	ld [rVBK], a
+	ld hl, vTiles0
+	ld bc, sScratch - vTiles0
+	xor a
+	call ByteFill
+	ld a, $0
+	ld [rVBK], a
+	ld hl, vTiles0
+	ld bc, sScratch - vTiles0
+	xor a
+	call ByteFill
+	hlcoord 0, 0, wAttrMap
+	ld bc, SCREEN_WIDTH * SCREEN_HEIGHT
+	xor a
+	call ByteFill
+	hlcoord 0, 0
+	ld bc, SCREEN_WIDTH * SCREEN_HEIGHT
+	xor a
+	call ByteFill
+	call ClearSprites
+	ret
+; 8197c
+
+Function8197c: ; 8197c
+	ld hl, DebugColorTestGFX + 1 tiles
+	ld de, vTiles2 tile DEBUGTEST_UP_ARROW
+	ld bc, 22 tiles
+	call CopyBytes
+	ld hl, DebugColorTestGFX
+	ld de, vTiles0
+	ld bc, 1 tiles
+	call CopyBytes
+	call LoadStandardFont
+	ld hl, vTiles1
+	lb bc, 8, 0
+.asm_8199d
+	ld a, [hl]
+	xor $ff
+	ld [hli], a
+	dec bc
+	ld a, c
+	or b
+	jr nz, .asm_8199d
+	ret
+; 819a7
+
+Function819a7: ; 819a7
+	ld a, [hCGB]
+	and a
+	ret z
+	ld a, [rSVBK]
+	push af
+	ld a, BANK(wBGPals2)
+	ld [rSVBK], a
+	ld hl, Palette_DebugBG
+	ld de, wBGPals2
+	ld bc, 16 palettes
+	call CopyBytes
+	ld a, 1 << rBGPI_AUTO_INCREMENT
+	ld [rBGPI], a
+	ld hl, Palette_DebugBG
+	ld c, 8 palettes
+	xor a
+.asm_819c8
+	ld [rBGPD], a
+	dec c
+	jr nz, .asm_819c8
+	ld a, 1 << rOBPI_AUTO_INCREMENT
+	ld [rOBPI], a
+	ld hl, Palette_DebugOB
+	ld c, 8 palettes
+.asm_819d6
+	ld a, [hli]
+	ld [rOBPD], a
+	dec c
+	jr nz, .asm_819d6
+	ld a, $94
+	ld [wc608], a
+	ld a, $52
+	ld [wc608 + 1], a
+	ld a, $4a
+	ld [wc608 + 2], a
+	ld a, $29
+	ld [wc608 + 3], a
+	pop af
+	ld [rSVBK], a
+	ret
+; 819f4
+
+Palette_DebugBG: ; 819f4
+INCLUDE "gfx/debug/bg.pal"
+
+Palette_DebugOB: ; 81a34
+INCLUDE "gfx/debug/ob.pal"
+; 81a74
+
+Function81a74: ; 81a74
+	call JoyTextDelay
+	ld a, [wJumptableIndex]
+	cp $4
+	jr nc, .asm_81a8b
+	ld hl, hJoyLast
+	ld a, [hl]
+	and SELECT
+	jr nz, .asm_81a9a
+	ld a, [hl]
+	and START
+	jr nz, .asm_81aab
+
+.asm_81a8b
+	ld a, [wJumptableIndex]
+	ld e, a
+	ld d, 0
+	ld hl, Jumptable_81acf
+	add hl, de
+	add hl, de
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	jp hl
+
+.asm_81a9a
+	call Function81eca
+	call Function81ac3
+	ld e, a
+	ld a, [wcf66]
+	inc a
+	cp e
+	jr c, .asm_81aba
+	xor a
+	jr .asm_81aba
+
+.asm_81aab
+	call Function81eca
+	ld a, [wcf66]
+	dec a
+	cp $ff
+	jr nz, .asm_81aba
+	call Function81ac3
+	dec a
+
+.asm_81aba
+	ld [wcf66], a
+	ld a, $0
+	ld [wJumptableIndex], a
+	ret
+; 81ac3
+
+Function81ac3: ; 81ac3
+; Looping back around the pic set.
+	ld a, [wd002]
+	and a
+	jr nz, .asm_81acc
+	ld a, NUM_POKEMON ; CELEBI
+	ret
+
+.asm_81acc
+	ld a, NUM_TRAINER_CLASSES - 1 ; MYSTICALMAN
+	ret
+; 81acf
+
+Jumptable_81acf: ; 81acf
+	dw Function81adb
+	dw Function81c18
+	dw Function81c33
+	dw Function81cc2
+	dw Function81d8e
+	dw Function81daf
+; 81adb
+
+Function81adb: ; 81adb
+	xor a
+	ld [hBGMapMode], a
+	hlcoord 0, 0
+	ld bc, SCREEN_WIDTH * SCREEN_HEIGHT
+	ld a, DEBUGTEST_BLACK
+	call ByteFill
+	hlcoord 1, 3
+	lb bc, 7, 18
+	ld a, DEBUGTEST_WHITE
+	call Bank20_FillBoxWithByte
+	hlcoord 11, 0
+	lb bc, 2, 3
+	ld a, DEBUGTEST_LIGHT
+	call Bank20_FillBoxWithByte
+	hlcoord 16, 0
+	lb bc, 2, 3
+	ld a, DEBUGTEST_DARK
+	call Bank20_FillBoxWithByte
+	call Function81bc0
+	call Function81bf4
+	ld a, [wcf66]
+	inc a
+	ld [wCurPartySpecies], a
+	ld [wd265], a
+	hlcoord 0, 1
+	ld de, wd265
+	lb bc, PRINTNUM_LEADINGZEROS | 1, 3
+	call PrintNum
+	ld a, [wd002]
+	and a
+	jr nz, .asm_81b7a
+	ld a, $1
+	ld [wUnownLetter], a
+	call GetPokemonName
+	hlcoord 4, 1
+	call PlaceString
+	xor a
+	ld [wBoxAlignment], a
+	hlcoord 12, 3
+	call _PrepMonFrontpic
+	ld de, vTiles2 tile $31
+	predef GetMonBackpic
+	ld a, $31
+	ld [hGraphicStartTile], a
+	hlcoord 2, 4
+	lb bc, 6, 6
+	predef PlaceGraphic
+	ld a, [wd003]
+	and a
+	jr z, .asm_81b66
+	ld de, String_81baf
+	jr .asm_81b69
+
+.asm_81b66
+	ld de, String_81bb4
+
+.asm_81b69
+	hlcoord 7, 17
+	call PlaceString
+	hlcoord 0, 17
+	ld de, String_81bb9
+	call PlaceString
+	jr .asm_81ba9
+
+.asm_81b7a
+	ld a, [wd265]
+	ld [wTrainerClass], a
+	callfar GetTrainerAttributes
+	ld de, wStringBuffer1
+	hlcoord 4, 1
+	call PlaceString
+	ld de, vTiles2
+	callfar GetTrainerPic
+	xor a
+	ld [wTempEnemyMonSpecies], a
+	ld [hGraphicStartTile], a
+	hlcoord 2, 3
+	lb bc, 7, 7
+	predef PlaceGraphic
+
+.asm_81ba9
+	ld a, $1
+	ld [wJumptableIndex], a
+	ret
+; 81baf
+
+String_81baf: db "レア", DEBUGTEST_BLACK, DEBUGTEST_BLACK, "@" ; rare (shiny)
+String_81bb4: db "ノーマル@" ; normal
+String_81bb9: db DEBUGTEST_A, "きりかえ▶@" ; (A) switches
+; 81bc0
+
+Function81bc0: ; 81bc0
+	decoord 0, 11, wAttrMap
+	hlcoord 2, 11
+	ld a, $1
+	call Function81bde
+	decoord 0, 13, wAttrMap
+	hlcoord 2, 13
+	ld a, $2
+	call Function81bde
+	decoord 0, 15, wAttrMap
+	hlcoord 2, 15
+	ld a, $3
+
+Function81bde: ; 81bde
+	push af
+	ld a, DEBUGTEST_UP_ARROW
+	ld [hli], a
+	ld bc, $f
+	ld a, DEBUGTEST_TICKS
+	call ByteFill
+	ld l, e
+	ld h, d
+	pop af
+	ld bc, $28
+	call ByteFill
+	ret
+; 81bf4
+
+Function81bf4: ; 81bf4
+	ld a, [wcf66]
+	inc a
+	ld l, a
+	ld h, $0
+	add hl, hl
+	add hl, hl
+	ld de, wOverworldMap
+	add hl, de
+	ld de, wc608
+	ld bc, 4
+	call CopyBytes
+	xor a
+	ld [wcf64], a
+	ld [wcf65], a
+	ld de, wc608
+	call Function81ea5
+	ret
+; 81c18
+
+Function81c18: ; 81c18
+	ld a, [hCGB]
+	and a
+	jr z, .asm_81c2a
+	ld a, $2
+	ld [hBGMapMode], a
+	call DelayFrame
+	call DelayFrame
+	call DelayFrame
+
+.asm_81c2a
+	call WaitBGMap
+	ld a, $2
+	ld [wJumptableIndex], a
+	ret
+; 81c33
+
+Function81c33: ; 81c33
+	ld a, [hCGB]
+	and a
+	jr z, .asm_81c69
+	ld a, [rSVBK]
+	push af
+	ld a, BANK(wBGPals2)
+	ld [rSVBK], a
+	ld hl, wBGPals2
+	ld de, wc608
+	ld c, $1
+	call Function81ee3
+	hlcoord 10, 2
+	ld de, wc608
+	call Function81ca7
+	hlcoord 15, 2
+	ld de, wc608 + 2
+	call Function81ca7
+	ld a, $1
+	ld [hCGBPalUpdate], a
+	ld a, $3
+	ld [wJumptableIndex], a
+	pop af
+	ld [rSVBK], a
+	ret
+
+.asm_81c69
+	ld hl, wSGBPals
+	ld a, 1
+	ld [hli], a
+	ld a, LOW(PALRGB_WHITE)
+	ld [hli], a
+	ld a, HIGH(PALRGB_WHITE)
+	ld [hli], a
+	ld a, [wc608]
+	ld [hli], a
+	ld a, [wc608 + 1]
+	ld [hli], a
+	ld a, [wc608 + 2]
+	ld [hli], a
+	ld a, [wc608 + 3]
+	ld [hli], a
+	xor a
+	ld [hli], a
+	ld [hli], a
+	ld [hl], a
+	ld hl, wSGBPals
+	call Function81f0c
+	hlcoord 10, 2
+	ld de, wc608
+	call Function81ca7
+	hlcoord 15, 2
+	ld de, wc608 + 2
+	call Function81ca7
+	ld a, $3
+	ld [wJumptableIndex], a
+	ret
+; 81ca7
+
+Function81ca7: ; 81ca7
+	inc hl
+	inc hl
+	inc hl
+	ld a, [de]
+	call Function81cbc
+	ld a, [de]
+	swap a
+	call Function81cbc
+	inc de
+	ld a, [de]
+	call Function81cbc
+	ld a, [de]
+	swap a
+
+Function81cbc: ; 81cbc
+	and $f
+	add DEBUGTEST_0
+	ld [hld], a
+	ret
+; 81cc2
+
+Function81cc2: ; 81cc2
+	ld a, [hJoyLast]
+	and B_BUTTON
+	jr nz, .asm_81cdf
+	ld a, [hJoyLast]
+	and A_BUTTON
+	jr nz, .asm_81ce5
+	ld a, [wcf64]
+	and $3
+	ld e, a
+	ld d, 0
+	ld hl, Jumptable_81d02
+	add hl, de
+	add hl, de
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	jp hl
+
+.asm_81cdf
+	ld a, $4
+	ld [wJumptableIndex], a
+	ret
+
+.asm_81ce5
+	ld a, [wd002]
+	and a
+	ret nz
+	ld a, [wd003]
+	xor $4
+	ld [wd003], a
+	ld c, a
+	ld b, 0
+	ld hl, PokemonPalettes
+	add hl, bc
+	call Function818fd
+	ld a, $0
+	ld [wJumptableIndex], a
+	ret
+; 81d02
+
+Jumptable_81d02: ; 81d02
+	dw Function81d0a
+	dw Function81d34
+	dw Function81d46
+	dw Function81d58
+; 81d0a
+
+Function81d0a: ; 81d0a
+	ld hl, hJoyLast
+	ld a, [hl]
+	and D_DOWN
+	jr nz, Function81d89
+	ld a, [hl]
+	and D_LEFT
+	jr nz, .asm_81d1d
+	ld a, [hl]
+	and D_RIGHT
+	jr nz, .asm_81d28
+	ret
+
+.asm_81d1d
+	xor a
+	ld [wcf65], a
+	ld de, wc608
+	call Function81ea5
+	ret
+
+.asm_81d28
+	ld a, $1
+	ld [wcf65], a
+	ld de, wc608 + 2
+	call Function81ea5
+	ret
+
+Function81d34: ; 81d34
+	ld hl, hJoyLast
+	ld a, [hl]
+	and D_DOWN
+	jr nz, Function81d89
+	ld a, [hl]
+	and D_UP
+	jr nz, Function81d84
+	ld hl, wc608 + 10
+	jr Function81d63
+
+Function81d46: ; 81d46
+	ld hl, hJoyLast
+	ld a, [hl]
+	and D_DOWN
+	jr nz, Function81d89
+	ld a, [hl]
+	and D_UP
+	jr nz, Function81d84
+	ld hl, wc608 + 11
+	jr Function81d63
+
+Function81d58: ; 81d58
+	ld hl, hJoyLast
+	ld a, [hl]
+	and D_UP
+	jr nz, Function81d84
+	ld hl, wc608 + 12
+
+Function81d63: ; 81d63
+	ld a, [hJoyLast]
+	and D_RIGHT
+	jr nz, Function81d70
+	ld a, [hJoyLast]
+	and D_LEFT
+	jr nz, Function81d77
+	ret
+
+Function81d70: ; 81d70
+	ld a, [hl]
+	cp $1f
+	ret nc
+	inc [hl]
+	jr Function81d7b
+
+Function81d77: ; 81d77
+	ld a, [hl]
+	and a
+	ret z
+	dec [hl]
+
+Function81d7b: ; 81d7b
+	call Function81e67
+	ld a, $2
+	ld [wJumptableIndex], a
+	ret
+
+Function81d84: ; 81d84
+	ld hl, wcf64
+	dec [hl]
+	ret
+
+Function81d89: ; 81d89
+	ld hl, wcf64
+	inc [hl]
+	ret
+; 81d8e
+
+Function81d8e: ; 81d8e
+	hlcoord 0, 10
+	ld bc, $a0
+	ld a, DEBUGTEST_BLACK
+	call ByteFill
+	hlcoord 2, 12
+	ld de, String_81fcd
+	call PlaceString
+	xor a
+	ld [wd004], a
+	call Function81df4
+	ld a, $5
+	ld [wJumptableIndex], a
+	ret
+; 81daf
+
+Function81daf: ; 81daf
+	ld hl, hJoyPressed
+	ld a, [hl]
+	and B_BUTTON
+	jr nz, .asm_81dbb
+	call Function81dc7
+	ret
+
+.asm_81dbb
+	ld a, $0
+	ld [wJumptableIndex], a
+	ret
+; 81dc1
+
+Function81dc1: ; 81dc1
+	ld hl, wJumptableIndex
+	set 7, [hl]
+	ret
+; 81dc7
+
+Function81dc7: ; 81dc7
+	ld hl, hJoyLast
+	ld a, [hl]
+	and D_UP
+	jr nz, .asm_81dd5
+	ld a, [hl]
+	and D_DOWN
+	jr nz, .asm_81de2
+	ret
+
+.asm_81dd5
+	ld a, [wd004]
+	cp $3b
+	jr z, .asm_81ddf
+	inc a
+	jr .asm_81ded
+
+.asm_81ddf
+	xor a
+	jr .asm_81ded
+
+.asm_81de2
+	ld a, [wd004]
+	and a
+	jr z, .asm_81deb
+	dec a
+	jr .asm_81ded
+
+.asm_81deb
+	ld a, $3b
+
+.asm_81ded
+	ld [wd004], a
+	call Function81df4
+	ret
+; 81df4
+
+Function81df4: ; 81df4
+	hlcoord 10, 11
+	call Function81e5e
+	hlcoord 10, 12
+	call Function81e5e
+	hlcoord 10, 13
+	call Function81e5e
+	hlcoord 10, 14
+	call Function81e5e
+	ld a, [wd004]
+	inc a
+	ld [wd265], a
+	predef GetTMHMMove
+	ld a, [wd265]
+	ld [wPutativeTMHMMove], a
+	call GetMoveName
+	hlcoord 10, 12
+	call PlaceString
+	ld a, [wd004]
+	call Function81e55
+	ld [wCurItem], a
+	predef CanLearnTMHMMove
+	ld a, c
+	and a
+	ld de, String_81e46
+	jr nz, .asm_81e3f
+	ld de, String_81e4d
+
+.asm_81e3f
+	hlcoord 10, 14
+	call PlaceString
+	ret
+; 81e46
+
+String_81e46: db "おぼえられる@" ; can be taught
+String_81e4d: db "おぼえられない@" ; cannot be taught
+; 81e55
+
+Function81e55: ; 81e55
+	cp $32
+	jr c, .asm_81e5b
+	inc a
+	inc a
+
+.asm_81e5b
+	add $bf
+	ret
+; 81e5e
+
+Function81e5e: ; 81e5e
+	ld bc, 10
+	ld a, DEBUGTEST_BLACK
+	call ByteFill
+	ret
+; 81e67
+
+Function81e67: ; 81e67
+	ld a, [wc608 + 10]
+	and $1f
+	ld e, a
+	ld a, [wc608 + 11]
+	and $7
+	sla a
+	swap a
+	or e
+	ld e, a
+	ld a, [wc608 + 11]
+	and $18
+	sla a
+	swap a
+	ld d, a
+	ld a, [wc608 + 12]
+	and $1f
+	sla a
+	sla a
+	or d
+	ld d, a
+	ld a, [wcf65]
+	and a
+	jr z, .asm_81e9c
+	ld a, e
+	ld [wc608 + 2], a
+	ld a, d
+	ld [wc608 + 3], a
+	ret
+
+.asm_81e9c
+	ld a, e
+	ld [wc608], a
+	ld a, d
+	ld [wc608 + 1], a
+	ret
+; 81ea5
+
+Function81ea5: ; 81ea5
+	ld a, [de]
+	and $1f
+	ld [wc608 + 10], a
+	ld a, [de]
+	and $e0
+	swap a
+	srl a
+	ld b, a
+	inc de
+	ld a, [de]
+	and $3
+	swap a
+	srl a
+	or b
+	ld [wc608 + 11], a
+	ld a, [de]
+	and $7c
+	srl a
+	srl a
+	ld [wc608 + 12], a
+	ret
+; 81eca
+
+Function81eca: ; 81eca
+	ld a, [wcf66]
+	inc a
+	ld l, a
+	ld h, $0
+	add hl, hl
+	add hl, hl
+	ld de, wOverworldMap
+	add hl, de
+	ld e, l
+	ld d, h
+	ld hl, wc608
+	ld bc, 4
+	call CopyBytes
+	ret
+; 81ee3
+
+Function81ee3: ; 81ee3
+.asm_81ee3
+	ld a, LOW(PALRGB_WHITE)
+	ld [hli], a
+	ld a, HIGH(PALRGB_WHITE)
+	ld [hli], a
+	ld a, [de]
+	inc de
+	ld [hli], a
+	ld a, [de]
+	inc de
+	ld [hli], a
+	ld a, [de]
+	inc de
+	ld [hli], a
+	ld a, [de]
+	inc de
+	ld [hli], a
+	xor a
+	ld [hli], a
+	ld [hli], a
+	dec c
+	jr nz, .asm_81ee3
+	ret
+; 81efc
+
+Bank20_FillBoxWithByte: ; 81efc
+; For some reason, we have another copy of FillBoxWithByte here
+.row
+	push bc
+	push hl
+.col
+	ld [hli], a
+	dec c
+	jr nz, .col
+	pop hl
+	ld bc, SCREEN_WIDTH
+	add hl, bc
+	pop bc
+	dec b
+	jr nz, .row
+	ret
+; 81f0c
+
+Function81f0c: ; 81f0c
+	ld a, [wcfbe]
+	push af
+	set 7, a
+	ld [wcfbe], a
+	call Function81f1d
+	pop af
+	ld [wcfbe], a
+	ret
+; 81f1d
+
+Function81f1d: ; 81f1d
+	ld a, [hl]
+	and $7
+	ret z
+	ld b, a
+.asm_81f22
+	push bc
+	xor a
+	ld [rJOYP], a
+	ld a, $30
+	ld [rJOYP], a
+	ld b, $10
+.asm_81f2c
+	ld e, $8
+	ld a, [hli]
+	ld d, a
+.asm_81f30
+	bit 0, d
+	ld a, $10
+	jr nz, .asm_81f38
+	ld a, $20
+
+.asm_81f38
+	ld [rJOYP], a
+	ld a, $30
+	ld [rJOYP], a
+	rr d
+	dec e
+	jr nz, .asm_81f30
+	dec b
+	jr nz, .asm_81f2c
+	ld a, $20
+	ld [rJOYP], a
+	ld a, $30
+	ld [rJOYP], a
+	ld de, 7000
+.asm_81f51
+	nop
+	nop
+	nop
+	dec de
+	ld a, d
+	or e
+	jr nz, .asm_81f51
+	pop bc
+	dec b
+	jr nz, .asm_81f22
+	ret
+; 81f5e
+
+Function81f5e: ; 81f5e
+	ld a, DEBUGTEST_BLACK
+	hlcoord 10, 0
+	ld [hl], a
+	hlcoord 15, 0
+	ld [hl], a
+	hlcoord 1, 11
+	ld [hl], a
+	hlcoord 1, 13
+	ld [hl], a
+	hlcoord 1, 15
+	ld [hl], a
+	ld a, [wJumptableIndex]
+	cp $3
+	jr nz, .asm_81fc9
+	ld a, [wcf64]
+	and a
+	jr z, .asm_81f8d
+	dec a
+	hlcoord 1, 11
+	ld bc, 2 * SCREEN_WIDTH
+	call AddNTimes
+	ld [hl], $ed
+
+.asm_81f8d
+	ld a, [wcf65]
+	and a
+	jr z, .asm_81f98
+	hlcoord 15, 0
+	jr .asm_81f9b
+
+.asm_81f98
+	hlcoord 10, 0
+
+.asm_81f9b
+	ld [hl], $ed
+	ld b, $70
+	ld c, $5
+	ld hl, wVirtualOAM
+	ld de, wc608 + 10
+	call .asm_81fb7
+	ld de, wc608 + 11
+	call .asm_81fb7
+	ld de, wc608 + 12
+	call .asm_81fb7
+	ret
+
+.asm_81fb7
+	ld a, b
+	ld [hli], a ; y
+	ld a, [de]
+	add a
+	add a
+	add 3 * TILE_WIDTH
+	ld [hli], a ; x
+	xor a
+	ld [hli], a ; tile id
+	ld a, c
+	ld [hli], a ; attributes
+	ld a, 2 * TILE_WIDTH
+	add b
+	ld b, a
+	inc c
+	ret
+
+.asm_81fc9
+	call ClearSprites
+	ret
+; 81fcd
+
+String_81fcd: ; 81fcd
+	db   "おわりますか？" ; Are you finished?
+	next "はい<DOT><DOT><DOT>", DEBUGTEST_A ; YES...(A)
+	next "いいえ<DOT><DOT>", DEBUGTEST_B ; NO..(B)
+	db   "@"
+; 81fe3
+
+DebugColorTestGFX:
+INCBIN "gfx/debug/color_test.2bpp"
+
+
+TilesetColorTest:
+	ret
+	xor a
+	ld [wJumptableIndex], a
+	ld [wcf64], a
+	ld [wcf65], a
+	ld [wcf66], a
+	ld [hMapAnims], a
+	call ClearSprites
+	call OverworldTextModeSwitch
+	call WaitBGMap2
+	xor a
+	ld [hBGMapMode], a
+	ld de, DebugColorTestGFX + 1 tiles
+	ld hl, vTiles2 tile DEBUGTEST_UP_ARROW
+	lb bc, BANK(DebugColorTestGFX), 22
+	call Request2bpp
+	ld de, DebugColorTestGFX
+	ld hl, vTiles1
+	lb bc, BANK(DebugColorTestGFX), 1
+	call Request2bpp
+	ld a, HIGH(vBGMap1)
+	ld [hBGMapAddress + 1], a
+	hlcoord 0, 0
+	ld bc, SCREEN_WIDTH * SCREEN_HEIGHT
+	ld a, DEBUGTEST_BLACK
+	call ByteFill
+	hlcoord 0, 0, wAttrMap
+	ld bc, SCREEN_WIDTH * SCREEN_HEIGHT
+	ld a, $7
+	call ByteFill
+	ld de, $15
+	ld a, DEBUGTEST_WHITE
+	call Function821d2
+	ld de, $1a
+	ld a, DEBUGTEST_LIGHT
+	call Function821d2
+	ld de, $1f
+	ld a, DEBUGTEST_DARK
+	call Function821d2
+	ld de, $24
+	ld a, DEBUGTEST_BLACK
+	call Function821d2
+	call Function821f4
+	call Function8220f
+	call WaitBGMap2
+	ld [wJumptableIndex], a
+	ld a, $40
+	ld [hWY], a
+	ret
+; 821d2
+
+Function821d2: ; 821d2
+	hlcoord 0, 0
+	call Function821de
+
+Function821d8: ; 821d8
+	ld a, [wcf64]
+	hlcoord 0, 0, wAttrMap
+
+Function821de: ; 821de
+	add hl, de
+rept 4
+	ld [hli], a
+endr
+	ld bc, $10
+	add hl, bc
+rept 4
+	ld [hli], a
+endr
+	ld bc, $10
+	add hl, bc
+rept 4
+	ld [hli], a
+endr
+	ret
+; 821f4
+
+Function821f4: ; 821f4
+	hlcoord 2, 4
+	call Function82203
+	hlcoord 2, 6
+	call Function82203
+	hlcoord 2, 8
+
+Function82203: ; 82203
+	ld a, DEBUGTEST_UP_ARROW
+	ld [hli], a
+	ld bc, $10 - 1
+	ld a, DEBUGTEST_TICKS
+	call ByteFill
+	ret
+; 8220f
+
+Function8220f: ; 8220f
+	ld a, [rSVBK]
+	push af
+	ld a, BANK(wBGPals1)
+	ld [rSVBK], a
+	ld a, [wcf64]
+	ld l, a
+	ld h, $0
+	add hl, hl
+	add hl, hl
+	add hl, hl
+	ld de, wBGPals1
+	add hl, de
+	ld de, wc608
+	ld bc, 8
+	call CopyBytes
+	ld de, wc608
+	call Function81ea5
+	pop af
+	ld [rSVBK], a
+	ret
+; 82236
+
+
+Function82236: ; 82236
+	ld hl, hJoyLast
+	ld a, [hl]
+	and SELECT
+	jr nz, .loop7
+	ld a, [hl]
+	and B_BUTTON
+	jr nz, .asm_82299
+	call Function822f0
+	ret
+
+.loop7
+	ld hl, wcf64
+	ld a, [hl]
+	inc a
+	and $7
+	cp $7
+	jr nz, .asm_82253
+	xor a
+
+.asm_82253
+	ld [hl], a
+	ld de, $15
+	call Function821d8
+	ld de, $1a
+	call Function821d8
+	ld de, $1f
+	call Function821d8
+	ld de, $24
+	call Function821d8
+	ld a, [rSVBK]
+	push af
+	ld a, BANK(wBGPals2)
+	ld [rSVBK], a
+	ld hl, wBGPals2
+	ld a, [wcf64]
+	ld bc, 1 palettes
+	call AddNTimes
+	ld de, wc608
+	ld bc, 1 palettes
+	call CopyBytes
+	pop af
+	ld [rSVBK], a
+	ld a, $2
+	ld [hBGMapMode], a
+	ld c, 3
+	call DelayFrames
+	ld a, $1
+	ld [hBGMapMode], a
+	ret
+
+.asm_82299
+	call ClearSprites
+	ld a, [hWY]
+	xor $d0
+	ld [hWY], a
+	ret
+; 822a3
+
+Function822a3: ; 822a3
+	ld a, [rSVBK]
+	push af
+	ld a, BANK(wBGPals2)
+	ld [rSVBK], a
+	ld hl, wBGPals2
+	ld a, [wcf64]
+	ld bc, 1 palettes
+	call AddNTimes
+	ld e, l
+	ld d, h
+	ld hl, wc608
+	ld bc, 1 palettes
+	call CopyBytes
+	hlcoord 1, 0
+	ld de, wc608
+	call Function81ca7
+	hlcoord 6, 0
+	ld de, wc608 + 2
+	call Function81ca7
+	hlcoord 11, 0
+	ld de, wc608 + 4
+	call Function81ca7
+	hlcoord 16, 0
+	ld de, wc608 + 6
+	call Function81ca7
+	pop af
+	ld [rSVBK], a
+	ld a, $1
+	ld [hCGBPalUpdate], a
+	call DelayFrame
+	ret
+; 822f0
+
+Function822f0: ; 822f0
+	ld a, [wcf65]
+	and 3
+	ld e, a
+	ld d, 0
+	ld hl, .dw
+	add hl, de
+	add hl, de
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	jp hl
+; 82301
+
+.dw ; 82301
+	dw Function82309
+	dw Function82339
+	dw Function8234b
+	dw Function8235d
+; 82309
+
+Function82309: ; 82309
+	ld hl, hJoyLast
+	ld a, [hl]
+	and D_DOWN
+	jr nz, Function8238c
+	ld a, [hl]
+	and D_LEFT
+	jr nz, .asm_8231c
+	ld a, [hl]
+	and D_RIGHT
+	jr nz, .asm_82322
+	ret
+
+.asm_8231c
+	ld a, [wcf66]
+	dec a
+	jr .asm_82326
+
+.asm_82322
+	ld a, [wcf66]
+	inc a
+
+.asm_82326
+	and $3
+	ld [wcf66], a
+	ld e, a
+	ld d, $0
+	ld hl, wc608
+	add hl, de
+	add hl, de
+	ld e, l
+	ld d, h
+	call Function81ea5
+	ret
+
+Function82339: ; 82338
+	ld hl, hJoyLast
+	ld a, [hl]
+	and D_DOWN
+	jr nz, Function8238c
+	ld a, [hl]
+	and D_UP
+	jr nz, Function82387
+	ld hl, wc608 + 10
+	jr Function82368
+
+Function8234b: ; 8234b
+	ld hl, hJoyLast
+	ld a, [hl]
+	and D_DOWN
+	jr nz, Function8238c
+	ld a, [hl]
+	and D_UP
+	jr nz, Function82387
+	ld hl, wc608 + 11
+	jr Function82368
+
+Function8235d: ; 8235d
+	ld hl, hJoyLast
+	ld a, [hl]
+	and D_UP
+	jr nz, Function82387
+	ld hl, wc608 + 12
+
+Function82368: ; 82368
+	ld a, [hJoyLast]
+	and D_RIGHT
+	jr nz, .asm_82375
+	ld a, [hJoyLast]
+	and D_LEFT
+	jr nz, .asm_8237c
+	ret
+
+.asm_82375
+	ld a, [hl]
+	cp $1f
+	ret nc
+	inc [hl]
+	jr .asm_82380
+
+.asm_8237c
+	ld a, [hl]
+	and a
+	ret z
+	dec [hl]
+
+.asm_82380
+	call Function82391
+	call Function822a3
+	ret
+
+Function82387: ; 82387
+	ld hl, wcf65
+	dec [hl]
+	ret
+
+Function8238c: ; 8238c
+	ld hl, wcf65
+	inc [hl]
+	ret
+; 82391
+
+Function82391: ; 82391
+	ld a, [wc608 + 10]
+	and $1f
+	ld e, a
+	ld a, [wc608 + 11]
+	and $7
+	sla a
+	swap a
+	or e
+	ld e, a
+	ld a, [wc608 + 11]
+	and $18
+	sla a
+	swap a
+	ld d, a
+	ld a, [wc608 + 12]
+	and $1f
+	sla a
+	sla a
+	or d
+	ld d, a
+	ld a, [wcf66]
+	ld c, a
+	ld b, $0
+	ld hl, wc608
+	add hl, bc
+	add hl, bc
+	ld a, e
+	ld [hli], a
+	ld [hl], d
+	ret
+; 823c6
+
+Function823c6: ; 823c6
+	ret
+
+Function823c7: ; 823c7
+	ret
+; 823c8
diff --git a/engine/menus/save.asm b/engine/menus/save.asm
new file mode 100644
index 000000000..7984c1612
--- /dev/null
+++ b/engine/menus/save.asm
@@ -0,0 +1,1210 @@
+SaveMenu: ; 14a1a
+	call LoadStandardMenuHeader
+	farcall DisplaySaveInfoOnSave
+	call SpeechTextBox
+	call UpdateSprites
+	farcall SaveMenu_CopyTilemapAtOnce
+	ld hl, Text_WouldYouLikeToSaveTheGame
+	call SaveTheGame_yesorno
+	jr nz, .refused
+	call AskOverwriteSaveFile
+	jr c, .refused
+	call PauseGameLogic
+	call _SavingDontTurnOffThePower
+	call ResumeGameLogic
+	call ExitMenu
+	and a
+	ret
+
+.refused
+	call ExitMenu
+	call ret_d90
+	farcall SaveMenu_CopyTilemapAtOnce
+	scf
+	ret
+
+SaveAfterLinkTrade: ; 14a58
+	call PauseGameLogic
+	farcall StageRTCTimeForSave
+	farcall BackupMysteryGift
+	call SavePokemonData
+	call SaveChecksum
+	call SaveBackupPokemonData
+	call SaveBackupChecksum
+	farcall BackupPartyMonMail
+	farcall SaveRTC
+	call ResumeGameLogic
+	ret
+; 14a83
+
+
+ChangeBoxSaveGame: ; 14a83 (5:4a83)
+	push de
+	ld hl, Text_SaveOnBoxSwitch
+	call MenuTextBox
+	call YesNoBox
+	call ExitMenu
+	jr c, .refused
+	call AskOverwriteSaveFile
+	jr c, .refused
+	call PauseGameLogic
+	call SavingDontTurnOffThePower
+	call SaveBox
+	pop de
+	ld a, e
+	ld [wCurBox], a
+	call LoadBox
+	call SavedTheGame
+	call ResumeGameLogic
+	and a
+	ret
+.refused
+	pop de
+	ret
+
+Link_SaveGame: ; 14ab2
+	call AskOverwriteSaveFile
+	jr c, .refused
+	call PauseGameLogic
+	call _SavingDontTurnOffThePower
+	call ResumeGameLogic
+	and a
+
+.refused
+	ret
+; 14ac2
+
+MoveMonWOMail_SaveGame: ; 14ac2
+	call PauseGameLogic
+	push de
+	call SaveBox
+	pop de
+	ld a, e
+	ld [wCurBox], a
+	call LoadBox
+	call ResumeGameLogic
+	ret
+; 14ad5
+
+MoveMonWOMail_InsertMon_SaveGame: ; 14ad5
+	call PauseGameLogic
+	push de
+	call SaveBox
+	pop de
+	ld a, e
+	ld [wCurBox], a
+	ld a, $1
+	ld [wSaveFileExists], a
+	farcall StageRTCTimeForSave
+	farcall BackupMysteryGift
+	call ValidateSave
+	call SaveOptions
+	call SavePlayerData
+	call SavePokemonData
+	call SaveChecksum
+	call ValidateBackupSave
+	call SaveBackupOptions
+	call SaveBackupPlayerData
+	call SaveBackupPokemonData
+	call SaveBackupChecksum
+	farcall BackupPartyMonMail
+	farcall BackupMobileEventIndex
+	farcall SaveRTC
+	call LoadBox
+	call ResumeGameLogic
+	ld de, SFX_SAVE
+	call PlaySFX
+	ld c, 24
+	call DelayFrames
+	ret
+; 14b34
+
+StartMoveMonWOMail_SaveGame: ; 14b34
+	ld hl, Text_SaveOnMoveMonWOMail
+	call MenuTextBox
+	call YesNoBox
+	call ExitMenu
+	jr c, .refused
+	call AskOverwriteSaveFile
+	jr c, .refused
+	call PauseGameLogic
+	call _SavingDontTurnOffThePower
+	call ResumeGameLogic
+	and a
+	ret
+
+.refused
+	scf
+	ret
+; 14b54
+
+PauseGameLogic: ; 14b54
+	ld a, $1
+	ld [wGameLogicPaused], a
+	ret
+; 14b5a
+
+ResumeGameLogic: ; 14b5a
+	xor a
+	ld [wGameLogicPaused], a
+	ret
+; 14b5f
+
+
+AddHallOfFameEntry: ; 14b5f
+	ld a, BANK(sHallOfFame)
+	call GetSRAMBank
+	ld hl, sHallOfFame + HOF_LENGTH * (NUM_HOF_TEAMS - 1) - 1
+	ld de, sHallOfFame + HOF_LENGTH * NUM_HOF_TEAMS - 1
+	ld bc, HOF_LENGTH * (NUM_HOF_TEAMS - 1)
+.loop
+	ld a, [hld]
+	ld [de], a
+	dec de
+	dec bc
+	ld a, c
+	or b
+	jr nz, .loop
+	ld hl, wOverworldMap
+	ld de, sHallOfFame
+	ld bc, HOF_LENGTH
+	call CopyBytes
+	call CloseSRAM
+	ret
+; 14b85
+
+SaveGameData: ; 14b85
+	call SaveGameData_
+	ret
+; 14b89
+
+AskOverwriteSaveFile: ; 14b89
+	ld a, [wSaveFileExists]
+	and a
+	jr z, .erase
+	call CompareLoadedAndSavedPlayerID
+	jr z, .yoursavefile
+	ld hl, Text_AnotherSaveFile
+	call SaveTheGame_yesorno
+	jr nz, .refused
+	jr .erase
+
+.yoursavefile
+	ld hl, Text_AlreadyASaveFile
+	call SaveTheGame_yesorno
+	jr nz, .refused
+	jr .ok
+
+.erase
+	call ErasePreviousSave
+
+.ok
+	and a
+	ret
+
+.refused
+	scf
+	ret
+; 14baf
+
+SaveTheGame_yesorno: ; 14baf
+	ld b, BANK(Text_WouldYouLikeToSaveTheGame)
+	call MapTextbox
+	call LoadMenuTextBox
+	lb bc, 0, 7
+	call PlaceYesNoBox
+	ld a, [wMenuCursorY]
+	dec a
+	call CloseWindow
+	push af
+	call ret_d90
+	pop af
+	and a
+	ret
+; 14bcb
+
+CompareLoadedAndSavedPlayerID: ; 14bcb
+	ld a, BANK(sPlayerData)
+	call GetSRAMBank
+	ld hl, sPlayerData + (wPlayerID - wPlayerData)
+	ld a, [hli]
+	ld c, [hl]
+	ld b, a
+	call CloseSRAM
+	ld a, [wPlayerID]
+	cp b
+	ret nz
+	ld a, [wPlayerID + 1]
+	cp c
+	ret
+; 14be3
+
+_SavingDontTurnOffThePower: ; 14be3
+	call SavingDontTurnOffThePower
+SavedTheGame: ; 14be6
+	call SaveGameData_
+	; wait 32 frames
+	ld c, $20
+	call DelayFrames
+	; copy the original text speed setting to the stack
+	ld a, [wOptions]
+	push af
+	; set text speed super slow
+	ld a, 3
+	ld [wOptions], a
+	; <PLAYER> saved the game!
+	ld hl, Text_PlayerSavedTheGame
+	call PrintText
+	; restore the original text speed setting
+	pop af
+	ld [wOptions], a
+	ld de, SFX_SAVE
+	call WaitPlaySFX
+	call WaitSFX
+	; wait 30 frames
+	ld c, $1e
+	call DelayFrames
+	ret
+; 14c10
+
+
+SaveGameData_: ; 14c10
+	ld a, 1
+	ld [wSaveFileExists], a
+	farcall StageRTCTimeForSave
+	farcall BackupMysteryGift
+	call ValidateSave
+	call SaveOptions
+	call SavePlayerData
+	call SavePokemonData
+	call SaveBox
+	call SaveChecksum
+	call ValidateBackupSave
+	call SaveBackupOptions
+	call SaveBackupPlayerData
+	call SaveBackupPokemonData
+	call SaveBackupChecksum
+	call UpdateStackTop
+	farcall BackupPartyMonMail
+	farcall BackupMobileEventIndex
+	farcall SaveRTC
+	ld a, BANK(sBattleTowerChallengeState)
+	call GetSRAMBank
+	ld a, [sBattleTowerChallengeState]
+	cp BATTLETOWER_RECEIVED_REWARD
+	jr nz, .ok
+	xor a
+	ld [sBattleTowerChallengeState], a
+.ok
+	call CloseSRAM
+	ret
+; 14c6b
+
+UpdateStackTop: ; 14c6b
+; sStackTop appears to be unused.
+; It could have been used to debug stack overflow during saving.
+	call FindStackTop
+	ld a, BANK(sStackTop)
+	call GetSRAMBank
+	ld a, [sStackTop + 0]
+	ld e, a
+	ld a, [sStackTop + 1]
+	ld d, a
+	or e
+	jr z, .update
+	ld a, e
+	sub l
+	ld a, d
+	sbc h
+	jr c, .done
+
+.update
+	ld a, l
+	ld [sStackTop + 0], a
+	ld a, h
+	ld [sStackTop + 1], a
+
+.done
+	call CloseSRAM
+	ret
+; 14c90
+
+FindStackTop: ; 14c90
+; Find the furthest point that sp has traversed to.
+; This is distinct from the current value of sp.
+	ld hl, wStack - $ff
+.loop
+	ld a, [hl]
+	or a
+	ret nz
+	inc hl
+	jr .loop
+; 14c99
+
+SavingDontTurnOffThePower: ; 14c99
+	; Prevent joypad interrupts
+	xor a
+	ld [hJoypadReleased], a
+	ld [hJoypadPressed], a
+	ld [hJoypadSum], a
+	ld [hJoypadDown], a
+	; Save the text speed setting to the stack
+	ld a, [wOptions]
+	push af
+	; Set the text speed to super slow
+	ld a, $3
+	ld [wOptions], a
+	; SAVING... DON'T TURN OFF THE POWER.
+	ld hl, Text_SavingDontTurnOffThePower
+	call PrintText
+	; Restore the text speed setting
+	pop af
+	ld [wOptions], a
+	; Wait for 16 frames
+	ld c, $10
+	call DelayFrames
+	ret
+; 14cbb
+
+
+ErasePreviousSave: ; 14cbb
+	call EraseBoxes
+	call EraseHallOfFame
+	call EraseLinkBattleStats
+	call EraseMysteryGift
+	call SaveData
+	call EraseBattleTowerStatus
+	ld a, BANK(sStackTop)
+	call GetSRAMBank
+	xor a
+	ld [sStackTop + 0], a
+	ld [sStackTop + 1], a
+	call CloseSRAM
+	ld a, $1
+	ld [wSavedAtLeastOnce], a
+	ret
+; 14ce2
+
+EraseLinkBattleStats: ; 14ce2
+	ld a, BANK(sLinkBattleStats)
+	call GetSRAMBank
+	ld hl, sLinkBattleStats
+	ld bc, sLinkBattleStatsEnd - sLinkBattleStats
+	xor a
+	call ByteFill
+	jp CloseSRAM
+; 14cf4
+
+EraseMysteryGift: ; 14cf4
+	ld a, BANK(sBackupMysteryGiftItem)
+	call GetSRAMBank
+	ld hl, sBackupMysteryGiftItem
+	ld bc, sBackupMysteryGiftItemEnd - sBackupMysteryGiftItem
+	xor a
+	call ByteFill
+	jp CloseSRAM
+; 14d06
+
+EraseHallOfFame: ; 14d06
+	ld a, BANK(sHallOfFame)
+	call GetSRAMBank
+	ld hl, sHallOfFame
+	ld bc, sHallOfFameEnd - sHallOfFame
+	xor a
+	call ByteFill
+	jp CloseSRAM
+; 14d18
+
+Unreferenced_Function14d18: ; 14d18
+; copy .Data to SRA4:a007
+	ld a, 4 ; MBC30 bank used by JP Crystal; inaccessible by MBC3
+	call GetSRAMBank
+	ld hl, .Data
+	ld de, $a007 ; address of MBC30 bank
+	ld bc, .DataEnd - .Data
+	call CopyBytes
+	jp CloseSRAM
+; 14d2c
+
+.Data: ; 14d2c
+	db $0d, $02, $00, $05, $00, $00
+	db $22, $02, $01, $05, $00, $00
+	db $03, $04, $05, $08, $03, $05
+	db $0e, $06, $03, $02, $00, $00
+	db $39, $07, $07, $04, $00, $05
+	db $04, $07, $01, $05, $00, $00
+	db $0f, $05, $14, $07, $05, $05
+	db $11, $0c, $0c, $06, $06, $04
+; 14d5c
+.DataEnd
+
+EraseBattleTowerStatus: ; 14d5c
+	ld a, BANK(sBattleTowerChallengeState)
+	call GetSRAMBank
+	xor a
+	ld [sBattleTowerChallengeState], a
+	jp CloseSRAM
+; 14d68
+
+SaveData: ; 14d68
+	call _SaveData
+	ret
+; 14d6c
+
+Unreferenced_Function14d6c: ; 14d6c
+	ld a, 4 ; MBC30 bank used by JP Crystal; inaccessible by MBC3
+	call GetSRAMBank
+	ld a, [$a60b] ; address of MBC30 bank
+	ld b, $0
+	and a
+	jr z, .ok
+	ld b, $2
+
+.ok
+	ld a, b
+	ld [$a60b], a ; address of MBC30 bank
+	call CloseSRAM
+	ret
+; 14d83
+
+Unreferenced_Function14d83: ; 14d83
+	ld a, 4 ; MBC30 bank used by JP Crystal; inaccessible by MBC3
+	call GetSRAMBank
+	xor a
+	ld [$a60c], a ; address of MBC30 bank
+	ld [$a60d], a ; address of MBC30 bank
+	call CloseSRAM
+	ret
+; 14d93
+
+Unreferenced_Function14d93: ; 14d93
+	ld a, 7 ; MBC30 bank used by JP Crystal; inaccessible by MBC3
+	call GetSRAMBank
+	xor a
+	ld [$a000], a ; address of MBC30 bank
+	call CloseSRAM
+	ret
+; 14da0
+
+
+HallOfFame_InitSaveIfNeeded: ; 14da0
+	ld a, [wSavedAtLeastOnce]
+	and a
+	ret nz
+	call ErasePreviousSave
+	ret
+; 14da9
+
+ValidateSave: ; 14da9
+	ld a, BANK(sCheckValue1) ; BANK(sCheckValue2)
+	call GetSRAMBank
+	ld a, SAVE_CHECK_VALUE_1
+	ld [sCheckValue1], a
+	ld a, SAVE_CHECK_VALUE_2
+	ld [sCheckValue2], a
+	jp CloseSRAM
+; 14dbb
+
+SaveOptions: ; 14dbb
+	ld a, BANK(sOptions)
+	call GetSRAMBank
+	ld hl, wOptions
+	ld de, sOptions
+	ld bc, wOptionsEnd - wOptions
+	call CopyBytes
+	ld a, [wOptions]
+	and $ff ^ (1 << NO_TEXT_SCROLL)
+	ld [sOptions], a
+	jp CloseSRAM
+; 14dd7
+
+SavePlayerData: ; 14dd7
+	ld a, BANK(sPlayerData)
+	call GetSRAMBank
+	ld hl, wPlayerData
+	ld de, sPlayerData
+	ld bc, wPlayerDataEnd - wPlayerData
+	call CopyBytes
+	ld hl, wCurrMapData
+	ld de, sCurrMapData
+	ld bc, wCurrMapDataEnd - wCurrMapData
+	call CopyBytes
+	jp CloseSRAM
+; 14df7
+
+SavePokemonData: ; 14df7
+	ld a, BANK(sPokemonData)
+	call GetSRAMBank
+	ld hl, wPokemonData
+	ld de, sPokemonData
+	ld bc, wPokemonDataEnd - wPokemonData
+	call CopyBytes
+	call CloseSRAM
+	ret
+; 14e0c
+
+SaveBox: ; 14e0c
+	call GetBoxAddress
+	call SaveBoxAddress
+	ret
+; 14e13
+
+SaveChecksum: ; 14e13
+	ld hl, sGameData
+	ld bc, sGameDataEnd - sGameData
+	ld a, BANK(sGameData)
+	call GetSRAMBank
+	call Checksum
+	ld a, e
+	ld [sChecksum + 0], a
+	ld a, d
+	ld [sChecksum + 1], a
+	call CloseSRAM
+	ret
+; 14e2d
+
+ValidateBackupSave: ; 14e2d
+	ld a, BANK(sBackupCheckValue1) ; BANK(sBackupCheckValue2)
+	call GetSRAMBank
+	ld a, SAVE_CHECK_VALUE_1
+	ld [sBackupCheckValue1], a
+	ld a, SAVE_CHECK_VALUE_2
+	ld [sBackupCheckValue2], a
+	call CloseSRAM
+	ret
+; 14e40
+
+SaveBackupOptions: ; 14e40
+	ld a, BANK(sBackupOptions)
+	call GetSRAMBank
+	ld hl, wOptions
+	ld de, sBackupOptions
+	ld bc, wOptionsEnd - wOptions
+	call CopyBytes
+	call CloseSRAM
+	ret
+; 14e55
+
+SaveBackupPlayerData: ; 14e55
+	ld a, BANK(sBackupPlayerData)
+	call GetSRAMBank
+	ld hl, wPlayerData
+	ld de, sBackupPlayerData
+	ld bc, wPlayerDataEnd - wPlayerData
+	call CopyBytes
+	ld hl, wCurrMapData
+	ld de, sBackupCurrMapData
+	ld bc, wCurrMapDataEnd - wCurrMapData
+	call CopyBytes
+	call CloseSRAM
+	ret
+; 14e76
+
+SaveBackupPokemonData: ; 14e76
+	ld a, BANK(sBackupPokemonData)
+	call GetSRAMBank
+	ld hl, wPokemonData
+	ld de, sBackupPokemonData
+	ld bc, wPokemonDataEnd - wPokemonData
+	call CopyBytes
+	call CloseSRAM
+	ret
+; 14e8b
+
+SaveBackupChecksum: ; 14e8b
+	ld hl, sBackupGameData
+	ld bc, sBackupGameDataEnd - sBackupGameData
+	ld a, BANK(sBackupGameData)
+	call GetSRAMBank
+	call Checksum
+	ld a, e
+	ld [sBackupChecksum + 0], a
+	ld a, d
+	ld [sBackupChecksum + 1], a
+	call CloseSRAM
+	ret
+; 14ea5
+
+
+TryLoadSaveFile: ; 14ea5 (5:4ea5)
+	call VerifyChecksum
+	jr nz, .backup
+	call LoadPlayerData
+	call LoadPokemonData
+	call LoadBox
+	farcall RestorePartyMonMail
+	farcall RestoreMobileEventIndex
+	farcall RestoreMysteryGift
+	call ValidateBackupSave
+	call SaveBackupOptions
+	call SaveBackupPlayerData
+	call SaveBackupPokemonData
+	call SaveBackupChecksum
+	and a
+	ret
+
+.backup
+	call VerifyBackupChecksum
+	jr nz, .corrupt
+	call LoadBackupPlayerData
+	call LoadBackupPokemonData
+	call LoadBox
+	farcall RestorePartyMonMail
+	farcall RestoreMobileEventIndex
+	farcall RestoreMysteryGift
+	call ValidateSave
+	call SaveOptions
+	call SavePlayerData
+	call SavePokemonData
+	call SaveChecksum
+	and a
+	ret
+
+.corrupt
+	ld a, [wOptions]
+	push af
+	set NO_TEXT_SCROLL, a
+	ld [wOptions], a
+	ld hl, Text_SaveFileCorrupted
+	call PrintText
+	pop af
+	ld [wOptions], a
+	scf
+	ret
+
+
+TryLoadSaveData: ; 14f1c
+	xor a
+	ld [wSaveFileExists], a
+	call CheckPrimarySaveFile
+	ld a, [wSaveFileExists]
+	and a
+	jr z, .backup
+
+	ld a, BANK(sPlayerData)
+	call GetSRAMBank
+	ld hl, sPlayerData + wStartDay - wPlayerData
+	ld de, wStartDay
+	ld bc, 8
+	call CopyBytes
+	ld hl, sPlayerData + wStatusFlags - wPlayerData
+	ld de, wStatusFlags
+	ld a, [hl]
+	ld [de], a
+	call CloseSRAM
+	ret
+
+.backup
+	call CheckBackupSaveFile
+	ld a, [wSaveFileExists]
+	and a
+	jr z, .corrupt
+
+	ld a, BANK(sBackupPlayerData)
+	call GetSRAMBank
+	ld hl, sBackupPlayerData + wStartDay - wPlayerData
+	ld de, wStartDay
+	ld bc, 8
+	call CopyBytes
+	ld hl, sBackupPlayerData + wStatusFlags - wPlayerData
+	ld de, wStatusFlags
+	ld a, [hl]
+	ld [de], a
+	call CloseSRAM
+	ret
+
+.corrupt
+	ld hl, DefaultOptions
+	ld de, wOptions
+	ld bc, wOptionsEnd - wOptions
+	call CopyBytes
+	call PanicResetClock
+	ret
+; 14f7c
+
+
+INCLUDE "data/default_options.asm"
+
+
+CheckPrimarySaveFile: ; 14f84
+	ld a, BANK(sCheckValue1) ; BANK(sCheckValue2)
+	call GetSRAMBank
+	ld a, [sCheckValue1]
+	cp SAVE_CHECK_VALUE_1
+	jr nz, .nope
+	ld a, [sCheckValue2]
+	cp SAVE_CHECK_VALUE_2
+	jr nz, .nope
+	ld hl, sOptions
+	ld de, wOptions
+	ld bc, wOptionsEnd - wOptions
+	call CopyBytes
+	call CloseSRAM
+	ld a, $1
+	ld [wSaveFileExists], a
+
+.nope
+	call CloseSRAM
+	ret
+; 14faf
+
+CheckBackupSaveFile: ; 14faf
+	ld a, BANK(sBackupCheckValue1) ; BANK(sBackupCheckValue2)
+	call GetSRAMBank
+	ld a, [sBackupCheckValue1]
+	cp SAVE_CHECK_VALUE_1
+	jr nz, .nope
+	ld a, [sBackupCheckValue2]
+	cp SAVE_CHECK_VALUE_2
+	jr nz, .nope
+	ld hl, sBackupOptions
+	ld de, wOptions
+	ld bc, wOptionsEnd - wOptions
+	call CopyBytes
+	ld a, $2
+	ld [wSaveFileExists], a
+
+.nope
+	call CloseSRAM
+	ret
+; 14fd7
+
+
+LoadPlayerData: ; 14fd7 (5:4fd7)
+	ld a, BANK(sPlayerData)
+	call GetSRAMBank
+	ld hl, sPlayerData
+	ld de, wPlayerData
+	ld bc, wPlayerDataEnd - wPlayerData
+	call CopyBytes
+	ld hl, sCurrMapData
+	ld de, wCurrMapData
+	ld bc, wCurrMapDataEnd - wCurrMapData
+	call CopyBytes
+	call CloseSRAM
+	ld a, BANK(sBattleTowerChallengeState)
+	call GetSRAMBank
+	ld a, [sBattleTowerChallengeState]
+	cp BATTLETOWER_RECEIVED_REWARD
+	jr nz, .not_4
+	ld a, BATTLETOWER_WON_CHALLENGE
+	ld [sBattleTowerChallengeState], a
+.not_4
+	call CloseSRAM
+	ret
+
+LoadPokemonData: ; 1500c
+	ld a, BANK(sPokemonData)
+	call GetSRAMBank
+	ld hl, sPokemonData
+	ld de, wPokemonData
+	ld bc, wPokemonDataEnd - wPokemonData
+	call CopyBytes
+	call CloseSRAM
+	ret
+; 15021
+
+LoadBox: ; 15021 (5:5021)
+	call GetBoxAddress
+	call LoadBoxAddress
+	ret
+
+VerifyChecksum: ; 15028 (5:5028)
+	ld hl, sGameData
+	ld bc, sGameDataEnd - sGameData
+	ld a, BANK(sGameData)
+	call GetSRAMBank
+	call Checksum
+	ld a, [sChecksum + 0]
+	cp e
+	jr nz, .fail
+	ld a, [sChecksum + 1]
+	cp d
+.fail
+	push af
+	call CloseSRAM
+	pop af
+	ret
+
+LoadBackupPlayerData: ; 15046 (5:5046)
+	ld a, BANK(sBackupPlayerData)
+	call GetSRAMBank
+	ld hl, sBackupPlayerData
+	ld de, wPlayerData
+	ld bc, wPlayerDataEnd - wPlayerData
+	call CopyBytes
+	ld hl, sBackupCurrMapData
+	ld de, wCurrMapData
+	ld bc, wCurrMapDataEnd - wCurrMapData
+	call CopyBytes
+	call CloseSRAM
+	ret
+
+LoadBackupPokemonData: ; 15067 (5:5067)
+	ld a, BANK(sBackupPokemonData)
+	call GetSRAMBank
+	ld hl, sBackupPokemonData
+	ld de, wPokemonData
+	ld bc, wPokemonDataEnd - wPokemonData
+	call CopyBytes
+	call CloseSRAM
+	ret
+
+VerifyBackupChecksum: ; 1507c (5:507c)
+	ld hl, sBackupGameData
+	ld bc, sBackupGameDataEnd - sBackupGameData
+	ld a, BANK(sBackupGameData)
+	call GetSRAMBank
+	call Checksum
+	ld a, [sBackupChecksum + 0]
+	cp e
+	jr nz, .fail
+	ld a, [sBackupChecksum + 1]
+	cp d
+.fail
+	push af
+	call CloseSRAM
+	pop af
+	ret
+
+
+_SaveData: ; 1509a
+	; This is called within two scenarios:
+	;   a) ErasePreviousSave (the process of erasing the save from a previous game file)
+	;   b) unused mobile functionality
+	; It is not part of a regular save.
+
+	ld a, BANK(sCrystalData)
+	call GetSRAMBank
+	ld hl, wCrystalData
+	ld de, sCrystalData
+	ld bc, wCrystalDataEnd - wCrystalData
+	call CopyBytes
+
+	; This block originally had some mobile functionality, but since we're still in
+	; BANK(sCrystalData), it instead overwrites the sixteen wEventFlags starting at 1:a603 with
+	; garbage from wd479. This isn't an issue, since ErasePreviousSave is followed by a regular
+	; save that unwrites the garbage.
+
+	ld hl, wd479
+	ld a, [hli]
+	ld [$a60e + 0], a
+	ld a, [hli]
+	ld [$a60e + 1], a
+
+	jp CloseSRAM
+
+
+_LoadData: ; 150b9
+	ld a, BANK(sCrystalData)
+	call GetSRAMBank
+	ld hl, sCrystalData
+	ld de, wCrystalData
+	ld bc, wCrystalDataEnd - wCrystalData
+	call CopyBytes
+
+	; This block originally had some mobile functionality to mirror _SaveData above, but instead it
+	; (harmlessly) writes the aforementioned wEventFlags to the unused wd479.
+
+	ld hl, wd479
+	ld a, [$a60e + 0]
+	ld [hli], a
+	ld a, [$a60e + 1]
+	ld [hli], a
+
+	jp CloseSRAM
+
+
+GetBoxAddress: ; 150d8
+	ld a, [wCurBox]
+	cp NUM_BOXES
+	jr c, .ok
+	xor a
+	ld [wCurBox], a
+
+.ok
+	ld e, a
+	ld d, 0
+	ld hl, BoxAddresses
+rept 5
+	add hl, de
+endr
+	ld a, [hli]
+	push af
+	ld a, [hli]
+	ld e, a
+	ld a, [hli]
+	ld d, a
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	pop af
+	ret
+; 150f9
+
+SaveBoxAddress: ; 150f9
+; Save box via wMisc.
+; We do this in three steps because the size of wMisc is less than
+; the size of sBox.
+	push hl
+; Load the first part of the active box.
+	push af
+	push de
+	ld a, BANK(sBox)
+	call GetSRAMBank
+	ld hl, sBox
+	ld de, wMisc
+	ld bc, (wMiscEnd - wMisc)
+	call CopyBytes
+	call CloseSRAM
+	pop de
+	pop af
+; Save it to the target box.
+	push af
+	push de
+	call GetSRAMBank
+	ld hl, wMisc
+	ld bc, (wMiscEnd - wMisc)
+	call CopyBytes
+	call CloseSRAM
+
+; Load the second part of the active box.
+	ld a, BANK(sBox)
+	call GetSRAMBank
+	ld hl, sBox + (wMiscEnd - wMisc)
+	ld de, wMisc
+	ld bc, (wMiscEnd - wMisc)
+	call CopyBytes
+	call CloseSRAM
+	pop de
+	pop af
+
+	ld hl, (wMiscEnd - wMisc)
+	add hl, de
+	ld e, l
+	ld d, h
+; Save it to the next part of the target box.
+	push af
+	push de
+	call GetSRAMBank
+	ld hl, wMisc
+	ld bc, (wMiscEnd - wMisc)
+	call CopyBytes
+	call CloseSRAM
+
+; Load the third and final part of the active box.
+	ld a, BANK(sBox)
+	call GetSRAMBank
+	ld hl, sBox + (wMiscEnd - wMisc) * 2
+	ld de, wMisc
+	ld bc, sBoxEnd - (sBox + (wMiscEnd - wMisc) * 2) ; $8e
+	call CopyBytes
+	call CloseSRAM
+	pop de
+	pop af
+
+	ld hl, (wMiscEnd - wMisc)
+	add hl, de
+	ld e, l
+	ld d, h
+; Save it to the final part of the target box.
+	call GetSRAMBank
+	ld hl, wMisc
+	ld bc, sBoxEnd - (sBox + (wMiscEnd - wMisc) * 2) ; $8e
+	call CopyBytes
+	call CloseSRAM
+
+	pop hl
+	ret
+; 1517d
+
+
+LoadBoxAddress: ; 1517d (5:517d)
+; Load box via wMisc.
+; We do this in three steps because the size of wMisc is less than
+; the size of sBox.
+	push hl
+	ld l, e
+	ld h, d
+; Load part 1
+	push af
+	push hl
+	call GetSRAMBank
+	ld de, wMisc
+	ld bc, (wMiscEnd - wMisc)
+	call CopyBytes
+	call CloseSRAM
+	ld a, BANK(sBox)
+	call GetSRAMBank
+	ld hl, wMisc
+	ld de, sBox
+	ld bc, (wMiscEnd - wMisc)
+	call CopyBytes
+	call CloseSRAM
+	pop hl
+	pop af
+
+	ld de, (wMiscEnd - wMisc)
+	add hl, de
+; Load part 2
+	push af
+	push hl
+	call GetSRAMBank
+	ld de, wMisc
+	ld bc, (wMiscEnd - wMisc)
+	call CopyBytes
+	call CloseSRAM
+	ld a, BANK(sBox)
+	call GetSRAMBank
+	ld hl, wMisc
+	ld de, sBox + (wMiscEnd - wMisc)
+	ld bc, (wMiscEnd - wMisc)
+	call CopyBytes
+	call CloseSRAM
+	pop hl
+	pop af
+; Load part 3
+	ld de, (wMiscEnd - wMisc)
+	add hl, de
+	call GetSRAMBank
+	ld de, wMisc
+	ld bc, sBoxEnd - (sBox + (wMiscEnd - wMisc) * 2) ; $8e
+	call CopyBytes
+	call CloseSRAM
+	ld a, BANK(sBox)
+	call GetSRAMBank
+	ld hl, wMisc
+	ld de, sBox + (wMiscEnd - wMisc) * 2
+	ld bc, sBoxEnd - (sBox + (wMiscEnd - wMisc) * 2) ; $8e
+	call CopyBytes
+	call CloseSRAM
+
+	pop hl
+	ret
+
+
+EraseBoxes: ; 151fb
+	ld hl, BoxAddresses
+	ld c, NUM_BOXES
+.next
+	push bc
+	ld a, [hli]
+	call GetSRAMBank
+	ld a, [hli]
+	ld e, a
+	ld a, [hli]
+	ld d, a
+	xor a
+	ld [de], a
+	inc de
+	ld a, -1
+	ld [de], a
+	inc de
+	ld bc, sBoxEnd - (sBox + 2)
+.clear
+	xor a
+	ld [de], a
+	inc de
+	dec bc
+	ld a, b
+	or c
+	jr nz, .clear
+	ld a, [hli]
+	ld e, a
+	ld a, [hli]
+	ld d, a
+	ld a, -1
+	ld [de], a
+	inc de
+	xor a
+	ld [de], a
+	call CloseSRAM
+	pop bc
+	dec c
+	jr nz, .next
+	ret
+; 1522d
+
+BoxAddresses: ; 1522d
+; dbww bank, address, address
+	dbww BANK(sBox1),  sBox1,  sBox1End
+	dbww BANK(sBox2),  sBox2,  sBox2End
+	dbww BANK(sBox3),  sBox3,  sBox3End
+	dbww BANK(sBox4),  sBox4,  sBox4End
+	dbww BANK(sBox5),  sBox5,  sBox5End
+	dbww BANK(sBox6),  sBox6,  sBox6End
+	dbww BANK(sBox7),  sBox7,  sBox7End
+	dbww BANK(sBox8),  sBox8,  sBox8End
+	dbww BANK(sBox9),  sBox9,  sBox9End
+	dbww BANK(sBox10), sBox10, sBox10End
+	dbww BANK(sBox11), sBox11, sBox11End
+	dbww BANK(sBox12), sBox12, sBox12End
+	dbww BANK(sBox13), sBox13, sBox13End
+	dbww BANK(sBox14), sBox14, sBox14End
+; 15273
+
+
+Checksum: ; 15273
+	ld de, 0
+.loop
+	ld a, [hli]
+	add e
+	ld e, a
+	ld a, 0
+	adc d
+	ld d, a
+	dec bc
+	ld a, b
+	or c
+	jr nz, .loop
+	ret
+; 15283
+
+
+Text_WouldYouLikeToSaveTheGame: ; 0x15283
+	; Would you like to save the game?
+	text_jump UnknownText_0x1c454b
+	db "@"
+; 0x15288
+
+Text_SavingDontTurnOffThePower: ; 0x15288
+	; SAVING… DON'T TURN OFF THE POWER.
+	text_jump UnknownText_0x1c456d
+	db "@"
+; 0x1528d
+
+Text_PlayerSavedTheGame: ; 0x1528d
+	; saved the game.
+	text_jump UnknownText_0x1c4590
+	db "@"
+; 0x15292
+
+Text_AlreadyASaveFile: ; 0x15292
+	; There is already a save file. Is it OK to overwrite?
+	text_jump UnknownText_0x1c45a3
+	db "@"
+; 0x15297
+
+Text_AnotherSaveFile: ; 0x15297
+	; There is another save file. Is it OK to overwrite?
+	text_jump UnknownText_0x1c45d9
+	db "@"
+; 0x1529c
+
+Text_SaveFileCorrupted: ; 0x1529c
+	; The save file is corrupted!
+	text_jump UnknownText_0x1c460d
+	db "@"
+; 0x152a1
+
+Text_SaveOnBoxSwitch: ; 0x152a1
+	; When you change a #MON BOX, data will be saved. OK?
+	text_jump UnknownText_0x1c462a
+	db "@"
+; 0x152a6
+
+Text_SaveOnMoveMonWOMail: ; 0x152a6
+	; Each time you move a #MON, data will be saved. OK?
+	text_jump UnknownText_0x1c465f
+	db "@"
+; 0x152ab
diff --git a/engine/menus/savemenu_copytilemapatonce.asm b/engine/menus/savemenu_copytilemapatonce.asm
new file mode 100644
index 000000000..9b50494a4
--- /dev/null
+++ b/engine/menus/savemenu_copytilemapatonce.asm
@@ -0,0 +1,77 @@
+SaveMenu_CopyTilemapAtOnce: ; 4cf45 (13:4f45)
+	ld a, [hCGB]
+	and a
+	jp z, WaitBGMap
+
+; The following is a modified version of CopyTilemapAtOnce.
+	ld a, [hBGMapMode]
+	push af
+	xor a
+	ld [hBGMapMode], a
+	ld a, [hMapAnims]
+	push af
+	xor a
+	ld [hMapAnims], a
+.WaitLY:
+	ld a, [rLY]
+	cp $60
+	jr c, .WaitLY
+
+	di
+	ld a, BANK(vBGMap2)
+	ld [rVBK], a
+	hlcoord 0, 0, wAttrMap
+	call .CopyTilemapAtOnce
+	ld a, BANK(vBGMap0)
+	ld [rVBK], a
+	hlcoord 0, 0
+	call .CopyTilemapAtOnce
+.WaitLY2:
+	ld a, [rLY]
+	cp $60
+	jr c, .WaitLY2
+	ei
+
+	pop af
+	ld [hMapAnims], a
+	pop af
+	ld [hBGMapMode], a
+	ret
+
+.CopyTilemapAtOnce: ; 4cf80 (13:4f80)
+	ld [hSPBuffer], sp ; $ffd9
+	ld sp, hl
+	ld a, [hBGMapAddress + 1]
+	ld h, a
+	ld l, 0
+	ld a, SCREEN_HEIGHT
+	ld [hTilesPerCycle], a
+	ld b, 1 << 1
+	ld c, LOW(rSTAT)
+
+.loop
+rept SCREEN_WIDTH / 2
+	pop de
+.loop\@
+	ld a, [$ff00+c]
+	and b
+	jr nz, .loop\@
+	ld [hl], e
+	inc l
+	ld [hl], d
+	inc l
+endr
+
+	ld de, BG_MAP_WIDTH - SCREEN_WIDTH
+	add hl, de
+	ld a, [hTilesPerCycle]
+	dec a
+	ld [hTilesPerCycle], a
+	jr nz, .loop
+
+	ld a, [hSPBuffer]
+	ld l, a
+	ld a, [hSPBuffer + 1]
+	ld h, a
+	ld sp, hl
+	ret