melonDS is a Nintendo DS emulator mainly developed by Arisotura (StapleButter). It was first ported to the Switch by Hydr8gon.

The goal is to do things right and fast, akin to blargSNES (but hopefully better).

How to install

• Download the latest release.
• Extract the release onto your SD card, so that there's /switch/melonds/ folder melonds.nro and some other files inside it.
• NAND, BIOS and firmware files go into /switch/melonds/ as well.
• ROM files can be placed anywhere on the SD card.

For DS mode the following files are necessary (in parantheses is how they should be named for melonDS to recognises them):

• ARM9 BIOS (bios9.bin)
• ARM7 BIOS (bios7.bin)
• DS mode firmware (firmware.bin)

For DSi mode the following files are necessary (in parantheses is how they should be named for melonDS to recognises them):

• DSi ARM9 BIOS (biosdsi9.rom)
• DSi ARM7 BIOS (biosdsi7.rom)
• DSi mode firmware (firmware_dsi.bin)
• NAND dump (nand.bin)

For information on how to dump those files from your own DS or DSi see here.

Notes

• Atmosphere title replacement to launch the hbmenu is the only supported method of running melonDS. To do so, press R while starting any game from the Switch's main menu to enter the hbmenu. Don't use the album.
• If you are using an older versions of this port, using the /melonds directory located at the SD card root is still possible.
• Since Release 5 the JIT recompiler isn't enabled by default, so make sure to enable (under Emulation Settings), since the interpreter is pretty slow.

FAQ

Q. How can I pause the emulation?

To pause the emulation, simultaneously press the ZL and ZR buttons.

Q. How can I fast forward?

To fast forward, press either the ZL or ZR button depending on which button is set to do a touchscreen click.

This, however, is not applicable in gyro mode because it is utilized for recalibration.

Q. What are the functions of Block Size, Branch Optimisations, Literal Optimisations, and Fast Memory settings?

It is recommended to keep these settings enabled or set to maximum at all times since they enhance performance. In case of issues with the JIT recompiler, modifying these settings can aid in identifying the problem faster.

Only adjust them when unexpected issues arise, and specify which setting, if any, affects the bug reports.

Q. Which settings should I use if I want to play with a Flip Grip?

To play with a Flip Grip, use the Global Rotation option, which rotates the entire GUI.

Shoutout to @uzimakiuchiha for providing me with a Flip Grip.

Q. What should I do if I want to play a game that requires holding the DS sideways (like Dr. Kawashima's Brain Training)?

To play a game that necessitates holding the DS sideways (like Dr. Kawashima's Brain Training), use the Screen rotation in the Display settings once the game has started.

It will also rotate the buttons, giving the impression that you are holding the DS that way.

Q. What is the shortcut to switch between focused screens quickly?

To switch between focused screens quickly, press down the right stick.

There is also an automatic mode available in the Display settings where the main screen is identified.

Q. How can I display only one screen at a time (even if it means stretching the screen to fit the whole display)?

Go to Display settings and set the Top aspect ratio and Bottom aspect ratio to 16:9, then select either Top only or Bottom only for Screen sizing.

Q. How do I use gyro control?

Enable gyro control in the Input settings, and press either ZL or ZR (depending on Left handed mode) to calibrate rotation.

As it utilizes gyroscopes and not IR like the Wiimote, it requires recentering if you change how you hold the Switch/Joy-Con.

Q. How can I access the DS menu to change system language?

Press Boot Firmware or disable Direct boot in the Emulation settings.

Q. Why won't a DSiWare dumped as a NDS file start?

DSiWare needs to be installed on the NAND to run properly.

If started from the file browser, it will load as a cartridge and fail to start.

Q. How can I provide microphone input (e.g., for games that require blowing into the microphone)?

To simulate blowing into the microphone, press down on the left stick.

Currently, proper microphone input via an external microphone is not supported.

How To Fully Play Nintendo DS Games on a Nintendo Switch (A Complete Guide) (Lil_Kunall)

Tested on FW 11.0.1 on Atmosphere 0.17.1.