GAME BOY  Dev  

Duo's GameBoy ASMSchool

Welcome, welcome, welcome! Here I have my ASMSchool lessons posted for all to read and learn about coding in assembly language for the GameBoy! Browse through what I have up so far and enjoy!

Lessons

• Introduction: What is the GameBoy? History and Details!
• Lesson 1: CPU basics and moving data around
• Lesson 2: Arithmetic and Logical operations
• Lesson 3: General Purpose Arithmetic and more!
• Lesson 4: Program flow control
• Lesson 5: GameBoy Hardware
• Lesson 6: Tools of the Trade
• Lesson 7: What the hell is RGBDS and WLA?
• Lesson 8: First things first
• Lesson 9: Our First Program (Hello World!) (source here)
• Lesson 10: (NOT FINISHED) Our Second Program (Displaying a picture and panning)
• Lesson 11: (NOT FINISHED) What's a Sprite?
• Lesson 12: (NOT FINISHED) Beep Beep?
• Lesson 13: (NOT FINISHED) Intro to Color GameBoy
• Lesson 14: (NOT FINISHED) Libraries
• Lesson 15: How to use the BGB debugger/emulator
• Instruction Set Reference
• Visual Memory Map
• Jeff's Include Files - A definate MUST

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Disassembling... hehehe

Why disassemble? Well there's a wealth of information and techniques to learn from. I've chosen a few different game types to get a good idea of how the different types of games are structured. I also chose the games based on the small size and AGE, since Nintendo doesn't really promote these games actively. I will be using the most excellent debugger BGB, written and maintained by beware. I suggest using this emulator/debugger for Gameboy development as it is highly accurate and actively maintained. NOTE: I will NOT post the "roms" to these games. What I will be posting is (legally) reverse-engineered source code with comments by me, for the pure and simple purpose of education.

Disassembly 1: Disassembly of Final Fantasy Legend 3

This lesson, when completed, will introduce you to the concept of a large-scale/small code event driven RPG engine with a compressed text storage/display system and some interesting self-modifying code.

Disassembly 2: Disassembly of Alleyway

This lesson, when completed, will analyze an action-puzzle type game with some ingenious collision detection ideas. (on a more personal note, I think that the Super Breakout game for GBC has pathetic physics and gameplay compared to this awesome 1989 original)

Disassembly 3: Disassembly of Super Mario Land

This lesson, when completed, will include an analysis of the principles of a platform "run-and-jump" type of game.

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Articles written by various coders

• The Infamous Pan Doc =) - by Pan/Anthrox
• Zelda GBC on a GBA - by Duo
• DMA Ideas - by The ZenPsycho
• Jump Table Ideas - by The ZenPsycho
• Look Up Table Ideas - by The ZenPsycho
• 2x Speed Sprite Problems - by Jan-Lieuwe Koopmans
• LCD Status Register - by Martin Korth
• CPU Timing Overview - by Groepaz/Hitmen
• General Memory Map - by Groepaz/Hitmen
• LCD Timing Diagram - by Groepaz/Hitmen
• How to use Common Interrupts - by Groepaz/Hitmen
• DMA Transfers - by Groepaz/Hitmen
• Intro to the GBC video system - by Jason
• Timer Interrupt - by Jonathan Waugh
• Spare Sprite RAM - by GeeBee
• SGB Commands - by kOOPa
• Link Port Notes - by Ian (James?)
• Tips for getting your programs to run on a real GB - by kOOPa
• Commonly used acronyms for GameBoy Development - by GeeBee and Jason
• Fast 2-player ideas - by GeeBee and Otaku
• Animated Water - by Marc Gale
• ASM Coding tips - by GeeBee
• Using the MBC3 - by bRILLO hEAD
• CPU Mnemonic comparison table - by Groepaz/Hitmen
• Game Genie code format - by Unknown
• Making your first GameBoy Game - by Mike Mika of Genetic Fantasia (very outdated document)

NOTE:

In no way do I claim to be the world's best ASM guru. I make no claims that the information presented on this website is 100% correct, though I try my best. I do not claim that the lessons contained within will make you an ASM coder either... it takes a sick, masochistic bastard to become an ASM coder. =) All games and logos and names and referenes that aren't mine are copyrighted to Nintendo, and several game development companies. I do not claim to own any of the names or games that are commercial and are mentioned on this site. Any and all reverse-engineering done by me and posted here is purely for educational purposes only, as this IS a site that teaches assembly coding on the GameBoy system.