melonDS

This is a fork of melonDS 1.1 with internet netplay, made for a 4-player co-op mod of Kingdom Hearts 358/2 Days. It is not an official melonDS release and is not supported by the melonDS team.

• System > Multiplayer > Netplay (internet)... hosts or joins a session over UDP (default port 7065). Every PC runs every player's DS in lockstep and only controller input goes over the network, so the local wireless link between the consoles never leaves the PC.
• Players who drop can join again into their seat; PCs that go out of sync are repaired from the host's state automatically.
• Player guide: packaging/README-netplay.txt. Design notes: src/netplay/Session.h, src/netplay/Lockstep.h.
• Builds as melonDS does (BUILD.md), plus enet and zstd; packaging/package-win.sh makes a standalone Windows folder (MSYS2 UCRT64).
• No game data is included: every player needs their own copy of the game.

DS emulator, sorta

The goal is to do things right and fast, akin to blargSNES (but hopefully better). But also to, you know, have a fun challenge :)

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How to use

Firmware boot (not direct boot) requires a BIOS/firmware dump from an original DS or DS Lite. DS firmwares dumped from a DSi or 3DS aren't bootable and only contain configuration data, thus they are only suitable when booting games directly.

Possible firmware sizes

• 128KB: DSi/3DS DS-mode firmware (reduced size due to lacking bootcode)
• 256KB: regular DS firmware
• 512KB: iQue DS firmware

DS BIOS dumps from a DSi or 3DS can be used with no compatibility issues. DSi BIOS dumps (in DSi mode) are not compatible. Or maybe they are. I don't know.

As for the rest, the interface should be pretty straightforward. If you have a question, don't hesitate to ask, though!

How to build

See BUILD.md for build instructions.

TODO LIST

• better DSi emulation
• better OpenGL rendering
• netplay
• the impossible quest of pixel-perfect 3D graphics
• support for rendering screens to separate windows
• emulating some fancy addons
• other non-core shit (debugger, graphics viewers, etc)

TODO LIST FOR LATER (low priority)

• big-endian compatibility (Wii, etc)
• LCD refresh time (used by some games for blending effects)
• any feature you can eventually ask for that isn't outright stupid

Credits

• Martin for GBAtek, a good piece of documentation
• Cydrak for the extra 3D GPU research
• limittox for the icon
• All of you comrades who have been testing melonDS, reporting issues, suggesting shit, etc

Licenses

melonDS is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

External

• Images used in the Input Config Dialog - see src/frontend/qt_sdl/InputConfig/resources/LICENSE.md