: Games were highly optimized for performance. Compilers often inline functions, unroll loops, and use clever bitwise math that looks incredibly convoluted when translated back to C.
Because an NDS ROM contains separate binaries for the ARM9 and ARM7 processors, a decompiler must target these binaries individually while tracking how they communicate via shared memory and Inter-Processor Communication (IPC) registers. Top NDS Decompiler Tools in the Industry
Ed-1T/NDS-Decompilation-Project-Maker: A tool to ... - GitHub
Reverse engineering code designed for 2004 hardware presents unique hurdles:
An NDS decompiler focuses heavily on the ARM9 and ARM7 binaries, as well as the accompanying overlays, converting their raw hexadecimal instructions into readable code. Top NDS Decompilers and Reverse Engineering Tools nds decompiler
undefined * FUN_02001234(void) // What is 0x04000000? It's the display controller. *(undefined2 *)0x4000000 = 0; return &DAT_02001240;
Ensure options like "Decompiler Parameter ID" and "ARM Constant Reference" are checked.
To develop an NDS decompiler, you could follow these steps:
: A project aimed at converting NDS resources into common formats and translating game code into readable formats. : Games were highly optimized for performance
: The community has developed custom loaders (like ghidra-nds-loader ) that automatically parse .nds files, map the memory regions correctly, and separate the ARM9 and ARM7 binaries.
Use ndstool to unpack the target game file into its raw components.
Extremely powerful, highly polished graph views, and unmatched analytical speed. Cons: Expensive commercial licensing fees.
The community has developed open-source plugins (such as ghidra-nds-loader ) that automatically recognize .nds files, map the correct memory regions for the ARM7 and ARM9 processors, and parse game overlays cleanly. Cost: 100% Free. 2. IDA Pro & IDA Free It's the display controller
Are you looking to do a or just a minor asset/code modification ?
Distributing decompiled source code that contains proprietary assets, copyrighted text, or intact logic owned by the original publisher (such as Nintendo) violates copyright law. Most successful open-source decompilation projects require users to provide their own legally dumped retail ROM to extract assets during compilation. Conclusion
The "NDS decompiler" is not a finished product but an ongoing dialogue between human curiosity and machine precision. It is a suite of tools—disassemblers, emulators, debuggers, and pseudo-C generators—wielded by patient digital archaeologists. While we may never have a button that turns The Legend of Zelda: Phantom Hourglass into pristine, commented C++ source, the current state of decompilation is transformative. It allows us to fix game-breaking bugs, translate forgotten RPGs, and understand the ingenious optimization tricks of early 2000s handheld developers.
For specific popular titles (like Pokémon Diamond/Pearl , Super Mario 64 DS , or The Legend of Zelda: Phantom Hourglass ), standalone GitHub "decompilation projects" exist. These are not automated tools, but collaborative community efforts utilizing custom toolchains to systematically match compiled binaries against hand-written C code until a 100% accurate, byte-matching source code repository is achieved. Step-by-Step: How to Decompile an NDS ROM