1 files changed, 96 insertions, 0 deletions
diff --git a/src/engine/unused_save_validation.asm b/src/engine/unused_save_validation.asm
new file mode 100644
index 0000000..f26bbcb
--- /dev/null
+++ b/src/engine/unused_save_validation.asm
@@ -0,0 +1,96 @@
+; this is a commented out routine for save data validation
+; sUnusedSaveDataValidationByte would be used to store some validation byte
+; and xor'd with $250 bytes in SRAM starting from sCardCollection
+; if the result wasn't 0, then it would mean there was
+; some save corruption and an error message would pop up
+StubbedUnusedSaveDataValidation:
+	ret
+
+UnusedSaveDataValidation: ; unreferenced
+	ldh a, [hBankSRAM]
+	or a
+	ret nz
+
+	push hl
+	push de
+	push bc
+	ld hl, sCardCollection
+	ld bc, $250
+	ld a, [sUnusedSaveDataValidationByte]
+	ld e, a
+.loop_xor
+	ld a, [hli]
+	xor e
+	ld e, a
+	dec bc
+	ld a, c
+	or b
+	jr nz, .loop_xor
+	ld a, e
+	pop bc
+	pop de
+	pop hl
+	or a
+	ret z
+
+	xor a
+	ld [wTileMapFill], a
+	ld hl, wDoFrameFunction
+	ld [hli], a
+	ld [hl], a
+	ldh [hSCX], a
+	ldh [hSCY], a
+	bank1call ZeroObjectPositionsAndToggleOAMCopy
+	call EmptyScreen
+	call LoadSymbolsFont
+	bank1call SetDefaultPalettes
+	ld a, [wConsole]
+	cp CONSOLE_SGB
+	jr nz, .not_sgb
+	ld a, $e4
+	ld [wOBP0], a
+	ld [wBGP], a
+	ld a, $01
+	ld [wFlushPaletteFlags], a
+.not_sgb
+	lb de, $38, $9f
+	call SetupText
+	ldtx hl, YourDataWasDestroyedSomehowText
+	bank1call DrawWholeScreenTextBox
+	ld a, SRAM_ENABLE
+	ld [MBC3SRamEnable], a
+	xor a
+	ldh [hBankSRAM], a
+	ld [MBC3SRamBank], a
+	ld [MBC3RTC], a
+	ld [MBC3SRamEnable], a
+	jp Reset
+
+	ret
+
+UnusedCalculateSaveDataValidationByte: ; unreferenced
+	ldh a, [hBankSRAM]
+	or a
+	ret nz
+	push hl
+	push de
+	push bc
+	ld hl, sCardCollection
+	ld bc, $250
+	ld e, $00
+.loop_xor
+	ld a, [hli]
+	xor e
+	ld e, a
+	dec bc
+	ld a, c
+	or b
+	jr nz, .loop_xor
+	ld a, SRAM_ENABLE
+	ld [MBC3SRamEnable], a
+	ld a, e
+	ld [sUnusedSaveDataValidationByte], a
+	pop bc
+	pop de
+	pop hl
+	ret