pokeheartgold-single-screen

A decompilation of Pokémon HeartGold and SoulSilver with a single-screen build mode (SINGLE_SCREEN). It is the source that ssrecomp recompiles into a native build of Pokémon SoulSilver for single-screen devices. The code is a fork of ctrl-cheeb-del/pokeheartgold, itself based on pret/pokeheartgold; the original tooling and decompilation are pret's work.

Fully decompiled: everything is C/C++ and both ROMs build byte-for-byte in the normal configuration. The single-screen build changes the game so that everything fits on one screen: the touch-screen parts of the interface (battle commands and moves, the bag, the party) are drawn where the top screen is, and the build publishes its menu and selection state so the ssrecomp frontend can lay it out for widescreen displays and controllers.

Made with heavy use of AI. Nearly all of the changes in this fork were written by an AI coding assistant (Anthropic's Claude, through Claude Code), directed and play-tested by the maintainer. Expect bugs a person would not have made, and review the code with that in mind before reusing it.

This repository contains no game assets. You need your own copy of the game to build a ROM; see INSTALL.md.

Not affiliated with or endorsed by Nintendo, Game Freak, The Pokémon Company or pret. Pokémon is a trademark of its owners. pret does not accept AI-generated code and does not want to be associated with this, so do not send anything from here upstream or ask them about it.

Screenshots

The single-screen ROM running in the ssrecomp frontend, drawn across a 16:9 screen:

Downloads

Setup programs for Windows and Linux are on the Releases page:

• pokeheartgold-single-screen-setup-windows-x86_64.exe
• pokeheartgold-single-screen-setup-linux-x86_64

What you give the setup program:

• mwccarm: a folder or zip with mwccarm/2.0/sp2p2/mwccarm.exe.
• Nitro SDK: one folder or zip holding tools/bin, ARM9-TS.lcf.template, ARM7-TS.lcf.template, mwldarm.response.template and, next to each other, the library folders NitroSDK, NitroSystem, NitroDWC, NitroWiFi, MSL_C, libCPS, libVCT, asm, src and include.
• ROM: your own SoulSilver (USA) .nds.

On Linux you also need make, python3, pkg-config, arm-none-eabi-gcc and wine. The setup tells you what is missing.

They carry the source only. You supply your own mwccarm compiler, the Nitro SDK (tools and the lib/ library sources) and your own SoulSilver (USA) ROM, from which the setup extracts the raw game files (the remaining sources are fetched from pret/pokeheartgold by tools/fetch_assets.py, see INSTALL.md); the setup places them, checks your build tools and builds SoulSilver-single-screen.nds. No ROM, compiler or SDK is distributed, and only the part of files/ that matches upstream pret/pokeheartgold is tracked. See INSTALL.md for the build tools each platform needs.

Building

Setup is in INSTALL.md. The single-screen build is for SoulSilver (USA); it is the only version the setup programs and asset script are tested with. This repository's build system can also make the following ROMs:

• pokeheartgold.us.nds sha1: 4fcded0e2713dc03929845de631d0932ea2b5a37
• pokesoulsilver.us.nds sha1: f8dc38ea20c17541a43b58c5e6d18c1732c7e582

To play the single-screen build you do not need to build this by hand: ssrecomp's setup program builds it from your ROM and recompiles the result.

Progress

Notes and credits

• docs/DECOMP-NOTES.md: work log of the decompilation.
• CREDITS.md: credits.

License and attribution

This is a fork of ctrl-cheeb-del/pokeheartgold, which is based on pret/pokeheartgold (the decompilation by the pret community and its contributors), with the single-screen changes added on top. It follows pret's terms; the single-screen changes are offered under the same terms.

Pokémon HeartGold and SoulSilver, and the game data and graphics under files/, belong to Nintendo, Creatures Inc. and GAME FREAK inc. This project is unofficial and not affiliated with or endorsed by them. It contains no ROM, Nintendo SDK or compiler: you supply your own legally obtained SoulSilver (USA) ROM, and the tools listed in INSTALL.md.

License

The single-screen changes and the recompilation frontend (frontend/) by ClickingMaster are released under the MIT license (see frontend/LICENSE), with the added requirement that derivative works credit "ClickingMaster" by name. The rest of the repository is the upstream pokeheartgold decompilation and is covered by its original terms (upstream has no license file); bundled tools in tools/ keep their own licenses. No game assets are included, and the game itself belongs to Nintendo, Game Freak and The Pokémon Company.