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SCHG How-to

Port Sonic 2 Level Select to Sonic 1

From Sonic Retro

Revision as of 06:41, 28 October 2017 by DelayHacks (talk | contribs)

Tutorial by DelayHacks. This is my first tutorial. You need to download level select by Esrael:

Download.svg Download Sonic 2 Level Select in Sonic 1
File: s2menu.rar (29 kB) (info)

and add him to disassembly.


Getting Level select in game

After download and add to disassembly go to "sonic1.asm" and go to end and you see this

; end of 'ROM'
EndOfRom:


		END

add this line before "; end of 'ROM'"

         include 's2_menu.asm' ; Sonic 2 Level Select

now go to

Title_ChkLevSel:
		tst.b	($FFFFFFE0).w		; check	if level select	code is	on
		beq.w	PlayLevel		; if not, play level
		btst	#iA,(Joypad|Held).w	; check if A is held
		beq.w	PlayLevel		; if not, play level
		moveq	#2,d0
		bsr.w	PalLoad2		; load level select pallet
		lea	($FFFFCC00).w,a1
		moveq	#0,d0
		move.w	#$DF,d1

and replace with this

Title_ChkLevSel:
		tst.b	($FFFFFFE0).w		; check	if level select	code is	on
		beq.w	PlayLevel		; if not, play level
		btst	#iA,(Joypad|Held).w	; check if A is held
		beq.w	PlayLevel		; if not, play level
		jmp     Level_Select_Menu ; if yes, goto Sonic 2 level select	
		moveq	#2,d0
		lea	($FFFFCC00).w,a1
		moveq	#0,d0
		move.w	#$DF,d1

Thats all. All permissions for this level select code goes to Esrael.