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Difference between revisions of "Sonic 2 (Simon Wai Prototype) Level Select in Sonic 1"

From Sonic Retro

m (Text replacement - "</asm>" to "</syntaxhighlight>")
Line 110: Line 110:
  
  
</asm>
+
</syntaxhighlight>
 
Notice anything here?
 
Notice anything here?
  
Line 146: Line 146:
 
bsr.w PlaySound_Special
 
bsr.w PlaySound_Special
 
bra.s LevelSelect
 
bra.s LevelSelect
</asm>
+
</syntaxhighlight>
  
 
We do not need the Japanese credits code, removed that junk. As for the levels, we want to start them with {{start}} but not exclusively just {{start}}, so an andi would be used there. Also, we want {{start}} to exit back to the Sega screen, and why not some nice music? Only {{B}} or {{C}} should play something on the sound test.
 
We do not need the Japanese credits code, removed that junk. As for the levels, we want to start them with {{start}} but not exclusively just {{start}}, so an andi would be used there. Also, we want {{start}} to exit back to the Sega screen, and why not some nice music? Only {{B}} or {{C}} should play something on the sound test.
Line 192: Line 192:
 
jmp MainGameLoop ;go to sega screen
 
jmp MainGameLoop ;go to sega screen
  
</asm>
+
</syntaxhighlight>
  
 
===Level Select Music Fix===
 
===Level Select Music Fix===
Line 204: Line 204:
  
 
bsr.w LevSelTextLoad
 
bsr.w LevSelTextLoad
</asm>
+
</syntaxhighlight>
  
 
and add under ''dbf d1,Title_ClrVram ; fill VRAM with 0'', these lines:
 
and add under ''dbf d1,Title_ClrVram ; fill VRAM with 0'', these lines:
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move.b  #$81,d0
 
move.b  #$81,d0
 
jsr PlaySound
 
jsr PlaySound
</asm>
+
</syntaxhighlight>
 
replace #$81 with your choice of song.
 
replace #$81 with your choice of song.
  
Line 221: Line 221:
 
jsr PlaySound
 
jsr PlaySound
 
bsr.w LevSelTextLoad
 
bsr.w LevSelTextLoad
</asm>
+
</syntaxhighlight>
 
Green Hill Zone music at the level select, how lovely. On the other hand, if you plan on using [[SCHG_How-to:Port_Sonic_2_Final_Sound_Driver_to_Sonic_1 | my Sonic 2 Sound Driver port]], try using music number $91 and PlayMusic as opposed to PlaySound.
 
Green Hill Zone music at the level select, how lovely. On the other hand, if you plan on using [[SCHG_How-to:Port_Sonic_2_Final_Sound_Driver_to_Sonic_1 | my Sonic 2 Sound Driver port]], try using music number $91 and PlayMusic as opposed to PlaySound.
  
Line 234: Line 234:
 
move.b ($FFFFF605).w,d1
 
move.b ($FFFFF605).w,d1
 
andi.b #$C,d1 ; is left/right pressed?
 
andi.b #$C,d1 ; is left/right pressed?
</asm>
+
</syntaxhighlight>
  
 
and change it to read out:
 
and change it to read out:
Line 244: Line 244:
 
andi.b #$4C,d1 ; is left/right/A pressed?
 
andi.b #$4C,d1 ; is left/right/A pressed?
  
</asm>
+
</syntaxhighlight>
 
instead.
 
instead.
  
Line 253: Line 253:
 
beq.s LevSel_NoMove ; if not, branch
 
beq.s LevSel_NoMove ; if not, branch
 
move.w ($FFFFFF84).w,d0
 
move.w ($FFFFFF84).w,d0
</asm>
+
</syntaxhighlight>
  
 
and add below:
 
and add below:
Line 259: Line 259:
 
btst #6,d1 ; is A pressed?
 
btst #6,d1 ; is A pressed?
 
bne.s LevSel_A ; if not, branch
 
bne.s LevSel_A ; if not, branch
</asm>
+
</syntaxhighlight>
  
 
Now locate:
 
Now locate:
Line 265: Line 265:
 
bcc.s LevSel_Right
 
bcc.s LevSel_Right
 
moveq #$4F,d0 ; if sound test moves below 0, set to $4F
 
moveq #$4F,d0 ; if sound test moves below 0, set to $4F
</asm>
+
</syntaxhighlight>
  
 
and add this routine under it to add {{A}} support to the level select:
 
and add this routine under it to add {{A}} support to the level select:
Line 273: Line 273:
 
beq.s LevSel_Right ; if not, branch
 
beq.s LevSel_Right ; if not, branch
 
add.w #16,d0 ; add $10 to sound test
 
add.w #16,d0 ; add $10 to sound test
</asm>
+
</syntaxhighlight>
  
 
Now the Sonic 1 level select will behave exactly like that of the one in Sonic 2 (Simon Wai prototype, except for night mode and split screen, those can be added manually if you get such a system working). Enjoy your alternative level select :)
 
Now the Sonic 1 level select will behave exactly like that of the one in Sonic 2 (Simon Wai prototype, except for night mode and split screen, those can be added manually if you get such a system working). Enjoy your alternative level select :)
 
{{S1Howtos}}
 
{{S1Howtos}}
 
[[Category:SCHG How-tos|{{PAGENAME}}]]
 
[[Category:SCHG How-tos|{{PAGENAME}}]]

Revision as of 21:30, 20 December 2015

(Original guide by Kram1024)

You probably wonder why Sonic 2 Beta has that level select that looks almost like the Sonic 1 level select, and how Sonic 2 Nick Arcade prototype has one that is the Sonic 1 level select. Well, that is what we are going to make the one in Sonic 1 behave like.

Overview

First, let's look at an overview of what our level select code looks like normally in Sonic 1 (this is from the Hivebrain disassembly): <asm>; ---------------------------------------------------------------------------

Level Select
---------------------------------------------------------------------------

LevelSelect: move.b #4,($FFFFF62A).w bsr.w DelayProgram bsr.w LevSelControls bsr.w RunPLC_RAM tst.l ($FFFFF680).w bne.s LevelSelect andi.b #$F0,($FFFFF605).w ; is A, B, C, or Start pressed? beq.s LevelSelect ; if not, branch move.w ($FFFFFF82).w,d0 cmpi.w #$14,d0 ; have you selected item $14 (sound test)? bne.s LevSel_Level_SS ; if not, go to Level/SS subroutine move.w ($FFFFFF84).w,d0 addi.w #$80,d0 tst.b ($FFFFFFE3).w ; is Japanese Credits cheat on? beq.s LevSel_NoCheat ; if not, branch cmpi.w #$9F,d0 ; is sound $9F being played? beq.s LevSel_Ending ; if yes, branch cmpi.w #$9E,d0 ; is sound $9E being played? beq.s LevSel_Credits ; if yes, branch

LevSel_NoCheat: cmpi.w #$94,d0 ; is sound $80-$94 being played? bcs.s LevSel_PlaySnd ; if yes, branch cmpi.w #$A0,d0 ; is sound $95-$A0 being played? bcs.s LevelSelect ; if yes, branch

LevSel_PlaySnd: bsr.w PlaySound_Special bra.s LevelSelect

===========================================================================

LevSel_Ending: ; XREF: LevelSelect move.b #$18,($FFFFF600).w ; set screen mode to $18 (Ending) move.w #$600,($FFFFFE10).w ; set level to 0600 (Ending) rts

===========================================================================

LevSel_Credits: ; XREF: LevelSelect move.b #$1C,($FFFFF600).w ; set screen mode to $1C (Credits) move.b #$91,d0 bsr.w PlaySound_Special ; play credits music move.w #0,($FFFFFFF4).w rts

===========================================================================

LevSel_Level_SS: ; XREF: LevelSelect add.w d0,d0 move.w LSelectPointers(pc,d0.w),d0 ; load level number bmi.w LevelSelect cmpi.w #$700,d0 ; check if level is 0700 (Special Stage) bne.s LevSel_Level ; if not, branch move.b #$10,($FFFFF600).w ; set screen mode to $10 (Special Stage) clr.w ($FFFFFE10).w ; clear level move.b #3,($FFFFFE12).w ; set lives to 3 moveq #0,d0 move.w d0,($FFFFFE20).w ; clear rings move.l d0,($FFFFFE22).w ; clear time move.l d0,($FFFFFE26).w ; clear score rts

===========================================================================

LevSel_Level: ; XREF: LevSel_Level_SS andi.w #$3FFF,d0 move.w d0,($FFFFFE10).w ; set level number

PlayLevel: ; XREF: ROM:00003246�j ... move.b #$C,($FFFFF600).w ; set screen mode to $0C (level) move.b #3,($FFFFFE12).w ; set lives to 3 moveq #0,d0 move.w d0,($FFFFFE20).w ; clear rings move.l d0,($FFFFFE22).w ; clear time move.l d0,($FFFFFE26).w ; clear score move.b d0,($FFFFFE16).w ; clear special stage number move.b d0,($FFFFFE57).w ; clear emeralds move.l d0,($FFFFFE58).w ; clear emeralds move.l d0,($FFFFFE5C).w ; clear emeralds move.b d0,($FFFFFE18).w ; clear continues move.b #$E0,d0 bsr.w PlaySound_Special ; fade out music rts

===========================================================================
---------------------------------------------------------------------------
Level select - level pointers
---------------------------------------------------------------------------

LSelectPointers: binclude misc\ls_point.bin align 2

---------------------------------------------------------------------------
Level select codes
---------------------------------------------------------------------------

LevelSelectCode_J: binclude misc\ls_jcode.bin align 2

LevelSelectCode_US: binclude misc\ls_ucode.bin align 2

===========================================================================


</syntaxhighlight> Notice anything here?

Button Fix, Part 1

A lot of stuff here we really do not need, as well as the fact that all buttons that are not the D-Pad seem to be used to play a sound or select a level. Let's fix that. <asm> LevelSelect: move.b #4,($FFFFF62A).w bsr.w DelayProgram bsr.w LevSelControls bsr.w RunPLC_RAM tst.l ($FFFFF680).w bne.s LevelSelect andi.b #$F0,($FFFFF605).w ; is A, B, C, or Start pressed? beq.s LevelSelect ; if not, branch move.w ($FFFFFF82).w,d0 cmpi.w #$14,d0 ; have you selected item $14 (sound test)? bne.s LevSel_Level_SS ; if not, go to Level/SS subroutine move.w ($FFFFFF84).w,d0 addi.w #$80,d0 tst.b ($FFFFFFE3).w ; is Japanese Credits cheat on? beq.s LevSel_NoCheat ; if not, branch cmpi.w #$9F,d0 ; is sound $9F being played? beq.s LevSel_Ending ; if yes, branch cmpi.w #$9E,d0 ; is sound $9E being played? beq.s LevSel_Credits ; if yes, branch

LevSel_NoCheat: cmpi.w #$94,d0 ; is sound $80-$94 being played? bcs.s LevSel_PlaySnd ; if yes, branch cmpi.w #$A0,d0 ; is sound $95-$A0 being played? bcs.s LevelSelect ; if yes, branch

LevSel_PlaySnd: bsr.w PlaySound_Special bra.s LevelSelect </syntaxhighlight>

We do not need the Japanese credits code, removed that junk. As for the levels, we want to start them with Start but not exclusively just Start, so an andi would be used there. Also, we want Start to exit back to the Sega screen, and why not some nice music? Only B or C should play something on the sound test.

The results should look like this:

<asm> LevelSelect: move.b #4,($FFFFF62A).w bsr.w DelayProgram bsr.w LevSelControls bsr.w RunPLC_RAM tst.l ($FFFFF680).w bne.s LevelSelect move.w ($FFFFFF82).w,d0 cmpi.w #$14,d0 ; have you selected item $14 (sound test)? bne.s LevSelLevCheckStart; if not, go to Level/SS subroutine cmpi.b #$80,($FFFFF605).w ; is Start pressed? beq.s LevSelStartPress ; if true, branch cmpi.b #$20,($FFFFF605).w ; is B pressed? beq.s LevSelBCPress ; if not, branch cmpi.b #$10,($FFFFF605).w ; is C pressed? beq.s LevSelBCPress ; if not, branch bra.s LevelSelect

===========================================================================

LevSelLevCheckStart: ; XREF: LevelSelect andi.b #$80,($FFFFF605).w ; is Start pressed? beq.s LevelSelect ; if not, branch bra.s LevSel_Level_SS

LevSelBCPress: ; XREF: LevelSelect move.w ($FFFFFF84).w,d0 addi.w #$80,d0 cmpi.w #$94,d0 ; is sound $80-$94 being played? bcs.s LevSel_PlaySnd ; if yes, branch cmpi.w #$A0,d0 ; is sound $95-$A0 being played? bcs.s LevelSelect ; if yes, branch

LevSel_PlaySnd: bsr.w PlaySound_Special bra.s LevelSelect

LevSelStartPress: ; XREF: LevelSelect move.b #$00,$FFFFF600 jmp MainGameLoop ;go to sega screen

</syntaxhighlight>

Level Select Music Fix

That fixes the level select so that it runs levels in a Sonic 2 manner, but it doesn't fix the music. Let's do that now.

Find: <asm> Title_ClrVram: move.l d0,(a6) dbf d1,Title_ClrVram ; fill VRAM with 0

bsr.w LevSelTextLoad </syntaxhighlight>

and add under dbf d1,Title_ClrVram ; fill VRAM with 0, these lines: <asm> move.b #$81,d0 jsr PlaySound </syntaxhighlight> replace #$81 with your choice of song.

the result should look like: <asm> Title_ClrVram: move.l d0,(a6) dbf d1,Title_ClrVram ; fill VRAM with 0 move.b #$81,d0 jsr PlaySound bsr.w LevSelTextLoad </syntaxhighlight> Green Hill Zone music at the level select, how lovely. On the other hand, if you plan on using my Sonic 2 Sound Driver port, try using music number $91 and PlayMusic as opposed to PlaySound.

Button Fix, Part 2

As you already know, A is not yet fixed, time to fix that button:

First, we will have to edit the "LevSel_SndTest" routine. $C (left and right) will not work for detecting A. We will need $4C (A/Left/Right) instead, so look in our function for: <asm> LevSel_SndTest: ; XREF: LevSelControls cmpi.w #$14,($FFFFFF82).w ; is item $14 selected? bne.s LevSel_NoMove ; if not, branch move.b ($FFFFF605).w,d1 andi.b #$C,d1 ; is left/right pressed? </syntaxhighlight>

and change it to read out: <asm> LevSel_SndTest: ; XREF: LevSelControls cmpi.w #$14,($FFFFFF82).w ; is item $14 selected? bne.s LevSel_NoMove ; if not, branch move.b ($FFFFF605).w,d1 andi.b #$4C,d1 ; is left/right/A pressed?

</syntaxhighlight> instead.

Now we can start working on adding the routine to handle A and increase the 16's ($10) part of the sound test:

locate: <asm> beq.s LevSel_NoMove ; if not, branch move.w ($FFFFFF84).w,d0 </syntaxhighlight>

and add below: <asm> btst #6,d1 ; is A pressed? bne.s LevSel_A ; if not, branch </syntaxhighlight>

Now locate: <asm> bcc.s LevSel_Right moveq #$4F,d0 ; if sound test moves below 0, set to $4F </syntaxhighlight>

and add this routine under it to add A support to the level select: <asm> LevSel_A: btst #6,d1 ; is A button pressed? beq.s LevSel_Right ; if not, branch add.w #16,d0 ; add $10 to sound test </syntaxhighlight>

Now the Sonic 1 level select will behave exactly like that of the one in Sonic 2 (Simon Wai prototype, except for night mode and split screen, those can be added manually if you get such a system working). Enjoy your alternative level select :)

SCHG How-To Guide: Sonic the Hedgehog (16-bit)
Fixing Bugs
Fix Demo Playback | Fix a Race Condition with Pattern Load Cues | Fix the SEGA Sound | Display the Press Start Button Text | Fix the Level Select Menu | Fix the Hidden Points Bug | Fix Accidental Deletion of Scattered Rings | Fix Ring Timers | Fix the Walk-Jump Bug | Correct Drowning Bugs | Fix the Death Boundary Bug | Fix the Camera Follow Bug | Fix Song Restoration Bugs | Fix the HUD Blinking | Fix the Level Select Graphics Bug | Fix a remember sprite related bug
Changing Design Choices
Change Spike Behavior | Collide with Water After Being Hurt | Fix Special Stage Jumping Physics | Improve the Fade In\Fade Out Progression Routines | Fix Scattered Rings' Underwater Physics | Remove the Speed Cap | Port the REV01 Background Effects | Port Sonic 2's Level Art Loader | Retain Rings Between Acts | Add Sonic 2 (Simon Wai Prototype) Level Select | Improve ObjectMove Subroutines | Port Sonic 2 Level Select
Adding Features
Add Spin Dash ( Part 1 / Part 2 / Part 3 / Part 4 ) | Add Eggman Monitor | Add Super Sonic | Add the Air Roll
Sound Features
Expand the Sound Index | Play Different Songs Per Act | Port Sonic 2 Final Sound Driver | Port Sonic 3's Sound Driver | Port Flamewing's Sonic 3 & Knuckles Sound Driver | Change The SEGA Sound
Extending the Game
Load Chunks From ROM | Add Extra Characters | Make an Alternative Title Screen | Use Dynamic Tilesets | Make GHZ Load Alternate Art | Make Ending Load Alternate Art | Add a New Zone | Set Up the Goggle Monitor | Add New Moves | Add a Dynamic Collision System | Dynamic Special Stage Walls System | Extend Sprite Mappings and Art Limit | Enigma Credits | Use Dynamic Palettes
Miscellaneous
Convert the Hivebrain 2005 Disassembly to ASM68K
Split Disassembly Guides
Set Up a Split Disassembly | Basic Level Editing | Basic Art Editing | Basic ASM Editing (Spin Dash)