Hacking Debug Build recreation of Gyakuten Saiban 1 (Japan)

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Introduction:
This is a recreation of the debug menu used in the development of Gyakuten Saiban 1 (Japan) which is found partly intact in a 2005 PC port and mostly functional in a 2008 PC port of the game.
After having decompiled a significant amount of code from the GBA versions of Gyakuten Saiban, I was able to piece together a theoretical debug build of the game.
The debug build is based on the original code from the two different PC ports alongside a demo version of Gyakuten Saiban 3, which actually has most of the logic code for the debug menu in the previous two games intact, despite a new debug menu being in development.
By reverse engineering the code from all three of these versions we have what I would call the closest thing you can get to a real debug build of Gyakuten Saiban 1.

The debug menu has a couple menus which go as follows in order

• A VRAM viewer
• A Sound test for testing music and sound effects
• An Animation viewer for the various character animations and sprites found throughout the game
• A menu for testing Court Scrolls
• A Flag editor possibly used in investigation sections to test different scenarios the player could be in
• And last A "Scenario" select screen used to quickly jump to a script in the game

Instructions:
Pressing select turns on or off the debug overlay.
By pressing A while holding Select you can open the debug menu at any time and exit the debug menus with Start.
Holding the L Button has the effect of slowing down how much the game loop runs, effectively making things slow motion; You can disable this option but there is no way to do so at the moment.
Each submenu has its own controls but they are simple enough so an explanation won't be necessary.

Overlay Explanation:
The numbers in the overlay have different meanings which we will now get to.

• The number on the top left shows if we are on an even or odd frame of the game, this could be useful if we have slowed the game down and need to be able to count frames to see where a problem with graphics might be.
• The middle numbers are in hex and represent the current state the game is in, this is useful for developers to know what the game state is and if there is a problem they can figure out why
• The two numbers on the right are for performance analysis and can be changed in code if needed, in its current state the left number displays on which scanline we are after the previous frame is updated for the PPU on the screen and the right number displays on which scanline we are after the game logic or BG decompression/copying is executed

Conclusion:
I've spent a lot of time decompiling the Gyakuten Saiban games and after all this time I wanted to actually do something with the knowledge I have gathered about the games, this hack is just supposed to be mostly a proof of concept and curiosity more than anything and I hope you have fun exploring it.
Source Code: github[dot]com[slash]atasro2/pwaa1/tree/debug
Download X Delta Patch (I recommend building the rom yourself): mega[dot]nz[slash]file/GEkBTCbT#KSJa6Vug3XMeEefJMDja2Pw49v8NuH9ibxpUFR464gM
The patch should be applied on a revision 0 rom of the game
SHA1: 15C0E3389709BB275C42E99ED25212D09E49E361

Screenshots: