Nintendo - DS (melonDS DS)¶

Background¶

A Nintendo DS emulator (with DSi support) by Arisotura and friends, ported to libretro by Jesse Talavera.

This is the newer version!

This version of the melonDS core is based on a newer version of the original emulator, and has more features than the older melonDS core. Use this one unless you're not ready to migrate.

Author/License¶

The melonDS DS core has been authored by

Jesse Talavera

The melonDS DS core is licensed under

GPLv3

A summary of the licenses behind RetroArch and its cores can be found here.

Extensions¶

Content that can be loaded by the melonDS core has one of the following file extensions:

.nds
.dsi
.ids

Databases¶

RetroArch database(s) that are associated with the melonDS DS core:

BIOS¶

Required or optional firmware files go in the frontend's system directory.

Filename	Description	md5sum
bios7.bin	NDS ARM7 BIOS - Optional	df692a80a5b1bc90728bc3dfc76cd948
bios9.bin	NDS ARM9 BIOS - Optional	a392174eb3e572fed6447e956bde4b25
firmware.bin	NDS Firmware - Optional	Varies
dsi_bios7.bin	DSi ARM7 BIOS - Required in DSi mode
dsi_bios9.bin	DSi ARM9 BIOS - Required in DSi mode
dsi_firmware.bin	DSi Firmware - Required in DSi mode	Varies
dsi_nand.bin	DSi NAND - Required in DSi mode	Varies

Features¶

Frontend-level settings or features that melonDS DS respects.

Feature	Supported
Restart	✔
Screenshots	✔
Saves	✔
States	✔¹
Rewind	✔¹
Netplay	✔²
Core Options	✔
RetroAchievements	✔
RetroArch Cheats	✔
Native Cheats	✔
Controls	✔
Remapping	✔
Multi-Mouse	✕
Rumble	✔
Sensors	✔
Camera	✕
Location	✕
Subsystem	✔
Softpatching	✔
Disk Control	✕
Username	✔
Language	✔
Crop Overscan	✕
LEDs	✕

Directories¶

The melonDS DS core's library name is 'melonDS DS'

The melonDS DS core saves/loads to/from these directories.

Frontend's Save directory¶

File	Description
*.srm	Cartridge battery save
dldi_sd_card.bin	Homebrew SD card image
dldi_sd_card.bin.idx	Homebrew SD card file index
dsi_sd_card.bin	DSi SD card image
dsi_sd_card.bin.idx	DSi SD card file index
*.public.sav	DSiWare public save data
*.private.sav	DSiWare private save data
*.banner.sav	DSiWare icon save data

Frontend's System directory¶

File	Description
melonDS DS/tmd/*.tmd	DSiWare title ID file
wfcsettings.bin	DS Wi-Fi settings (built-in BIOS only)

Frontend's State directory¶

File	Description
*.state#	State

Geometry and timing¶

The melonDS DS core's core provided FPS is 59.898307800293 FPS.
The melonDS DS core's core provided sample rate is 32768 Hz.
The melonDS DS core's base width depends on the screen layout and configured renderer.
The melonDS DS core's base height depends on the screen layout and configured renderer.
The melonDS DS core's max width depends on the screen layout and configured renderer.
The melonDS DS core's max height depends on the screen layout and configured renderer.
The melonDS DS core's core-provided aspect ratio depends on the screen layout and configured renderer.

Subsystems¶

melonDS DS uses subsystems to enable inserting GBA ROMs into the emulated Slot-2. GBA save data (if any) must be loaded explicitly. Subsystems are not used for DSi mode.

Subsystem	Description
gba	NDS ROM in Slot-1, GBA ROM in Slot-2 with optional save data
gbanosav	NDS ROM in Slot-1, GBA ROM in Slot-2 with no GBA save data

Not for playing GBA games.

melonDS can load Game Boy Advance ROMs and save data for the purpose of Slot-2 connectivity, but it cannot actually play GBA games. Use a GBA core instead.

Additional BIOS images are not required.

Wi-Fi¶

melonDS DS fully supports emulating Nintendo WFC services on all platforms. You can choose from one of several preconfigured servers in the core options menu, with Kaeru WFC being the default.

If there's another server you'd like to use, you can set its DNS address from within the emulated console's Wi-Fi settings menu.

Not related to netplay!

Wi-fi emulation is not related to LAN-based netplay.

LAN Netplay¶

Coming soon...

DSi¶

melonDS DS supports DSi mode, which allows you to play DSi-enhanced games and DSiWare. There is no need to prepare a NAND image externally; when selecting a DSiWare game from RetroArch, it (and its previously-exported save data) will be temporarily installed on the configured NAND image. At the end of the session, the save data will be exported to the frontend's save directory and the DSiWare will be uninstalled.

Screen Layouts¶

melonDS DS supports a variety of screen layouts, including sideways rotation; you can configure a particular sequence of available layouts in the core options, and cycle through them with the Next Screen Layout button. Best used with per-game core option overrides.

Controllers¶

The melonDS DS core supports the following device type(s) in the controls menu, bolded device types are the default for the specified user(s):

User 1 device types¶

None - Doesn't disable input. There's no reason to switch to this.
Nintendo DS - Joypad - Stay on this.

Future device types may be added to include peripherals that provided additional inputs.

Device tables¶

Joypad¶

User 1 input descriptors	RetroPad Inputs
B
Y
Select
Start
Up
Down
Left
Right
A
X
L
R
Microphone
Next Screen Layout
Move Virtual Cursor
Close Lid
Touch Virtual Cursor

Migrating from melonDS 2021¶

melonDS DS is intended to replace the legacy melonDS core. If you have existing data you'd like to migrate, follow these steps.

Save Files¶

The save data format is unchanged between the legacy core and melonDS DS. However, the method used to save game data internally has changed.

You'll need to do two things:

Go to the RetroArch save directory and rename the "melonDS" folder to "melonDS DS" (if it exists)
Rename the save files from .sav to .srm.

Savestates¶

Savestates taken in the legacy core cannot be migrated to melonDS DS. In the time since the last release of the legacy core, the savestate format has changed upstream. Save your game normally before migrating your data to melonDS DS.

Config Files¶

Rename the following directories to melonDS DS:

$RETROARCH_ROOT/config/melonDS to melonDS DS.
$RETROARCH_ROOT/config/remaps/melonDS to melonDS DS.
Rename any files inside these directories named melonDS.opt to melonDS DS.opt.

Cheats¶

Rename $RETROARCH_ROOT/cheats/melonDS to melonDS DS. Cheat support is unchanged.

System Files¶

melonDS DS will detect system files (BIOS, firmware, NAND) in the system directory, so no action is required from you. However, melonDS DS will prefer system files in the "melonDS DS" subdirectory.

Compatibility¶

Upstream melonDS Forums Compatibility section