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EmuDeck guide melonDS Tips and Tricks

Open Source BIOS

The open source BIOS is enabled by default for melonDS. This means that BIOS for Nintendo DS games is optional. However, some games may not perform as expected with the open source BIOS or you may need additional features provided by console dumped BIOS. You may also prefer to use DSI BIOS which allow you to play DSIWare games.

In order to use console dumped BIOS, you may place the files required into the Emulation/bios folder. You will also need to enable Use external BIOS/firmware files in the melonDS GUI.

melonDS Open Source BIOS

How to Configure Multiplayer

This section is strictly referring to local multiplayer. melonDS multiplayer on the Steam Deck can only be done in Desktop Mode.

  1. In Desktop Mode, open melonDS
  2. Click System, click Multiplayer, Launch new instance
  3. On each window of melonDS, click Config, Input and hotkeys
  4. In the drop-down menu to the right of Joystick, select your controller
  5. Steam Deck/Player 1: Microsoft X-Box 360 pad 0
  6. Player 2: Microsoft X-Box 360 pad 1
  7. Player 3: Microsoft X-Box 360 pad 2
  8. Player 4: Microsoft X-Box 360 pad 3
  9. Open the game in each melonDS window and you will be able to play multiplayer

You can determine which melonDS window corresponds to what player by looking at the menu bar at the top. Each new melonDS window will have a corresponding (#).

How to Configure Settings

Game Mode

If you are playing in Game Mode, make sure you have the correct "Steam Input" profile applied. For more information, see the Hotkeys section.

While in game, press Select + R3 to exit full screen. While melonDS is windowed, you will have access to the settings at the top of the screen. Adjust these options to your liking. After you have made your changes, press Select + R3 again to switch melonDS back to full screen.

After you have made your changes and you are ready to exit your game, do not use the STEAM butto to exit out of the game. If you use the STEAM button, any changes you have made will be reverted.

Press Select + R3 again to exit full screen. In the top right, click File, click Quit. You will only need to do this when you are changing settings. Otherwise, you may simply use the STEAM button as usual.

Desktop Mode

In Desktop Mode, open melonDS. Adjust any options to your liking. In the top right, click File, click Quit.

Do not click the X button in the top right to exit out of melonDS. If you use the X button, any changes will be reverted.

How to Use Cheats

Note: melonDS does not currently support importing cheats from a database file.

How to Enable Cheats in melonDS

  1. Open melonDS
  2. Click System at the top
  3. Check Enable cheats

How to Download the Cheats Database

  1. Open https://db.universal-team.net/ds/ndsi-cheat-databases, right click cheats.xml, and click Save As
  2. Place it in Emulation/storage/melonds/cheats
  3. This folder placement is optional, you may place it wherever you want
  4. To view, right click cheats.xml, open with a text editor of your choice

How to Use the Cheats Database

Note: It's recommended you do this in Desktop mode so you can easily copy from the cheats database into MelonDS. After adding cheats, you can use MelonDS in Game Mode.

  1. Open the cheats.xml you downloaded from the How to Download the Cheats Database section
  2. CTRL + F the game you are adding cheats to
  3. Copy the blocks of alphanumerical strings between the two <codes> <codes> for your respective cheat
  4. Example:
  5. Open MelonDS
  6. Open a ROM
  7. Click System at the top
  8. Click Setup cheat codes
  9. Create a New Category, you may name it whatever you would like
  10. Click New AR Code

  11. Match the name of the AR Code to the cheat you located in Step 3

  12. The name is flexible, you may name it whatever you would like

  13. Paste the code you copied from Step 3, it will appear as red text

  14. Format the cheat so there are two blocks of code per line
    • Original:
    • Corrected:
  15. Some cheats are automatically activated, others will require a button combo. Look at the cheats.xml file to see if a button combo is required to activate your cheat

How to Set Up DSIWare

The Nintendo DSI requires DSI specific BIOS. Place all of the files from the list below directly in Emulation/bios.

  • dsi_bios9.bin
  • dsi_bios7.bin
  • dsi_firmware.bin
  • dsi_nand.bin

Note:

  • The BIOS must be named exactly as above. BIOS with any deviations from the above will not work. Make sure you have the proper casing, characters, and spelling.
  • BIOS must be placed in Emulation/bios. If you create a sub-folder, the BIOS will not be picked up and Nintendo DSI games will not work.

Preface: Generally, DSIWare games are named 00000000 with no file extension. This section assumes you have these types of DSIWare ROMs.

  1. Place your DSI BIOS in Emulation/bios
  2. Place your DSIWare ROMs in Emulation/roms/nds
  3. Right click the DSIWare ROM in Emulation/roms/nds, click Rename, rename it from 00000000 to GAMENAME.app
  4. Replace GAMENAME with the name of the DSIWare game
  5. For example:
    • Original file name: 00000000
    • Updated file name: X-Scape.app
  6. In Desktop Mode, open melonDS
  7. At the top, select Config, Emu Settings
  8. On the General tab, change the Console type to DSi (experimental)
  9. How to Set Up DSIWare 1
  10. On the DS-mode tab, check Use external BIOS/firmware files, close out of this menu
  11. How to Set Up DSIWare 2
  12. At the top, select System, Manage DSi titles
  13. On the DSi Title Manager screen, select Import title
  14. Select your GAMENAME.app as the Executable
  15. Under Metadata, select Download from NUS, close out of this menu
  16. Select File, Boot Firmware
  17. Select your newly-installed DSiWare game and start playing

Steam ROM Manager and ES-DE

Both EmuDeck's Steam ROM Manager parser for melonDS (Standalone) and ES-DE support the .app file extension. As long as your DSIWare ROMs are in Emulation/roms/nds, you may use either option to play your DSIWare ROMs in Game Mode.

Do note that your ROM may not have art on SteamGridDB or metadata on ES-DE's scraping websites. Follow the links below if you would like to add art or metadata to one of these websites.

How to Play Nintendo DS Games in Book Mode

A handful of Nintendo DS games require portrait orientation. For these games, you will need to rotate the Steam Deck screen in order to play them. Fortunately, it's a simple process.

Here's How

  1. In Game Mode, select the EmuDeck - Controller Hotkeys profile if you are playing a game directly from Game Mode or the EmuDeck - Frontend Controller Hotkeys profile if you are playing through ES-DE or Pegasus
  2. How to Select a Steam Input Profile
  3. Open the game, use the Steam Input profile and select the Fullscreen hotkey
  4. At the top, press Config, Screen Rotation, 270

Original:

Rotated:

How to Customize the Screen Layout

By default, EmuDeck configures melonDS' screens to use a hybrid layout, meaning there is a large top screen on the left side of the screen and a mini top and bottom screen of the Nintendo DS on the right. If you would rather a different layout, it is fairly easy to customize.

Here's How

  1. In Game Mode, select the EmuDeck - Controller Hotkeys profile if you are playing a game directly from Game Mode or the EmuDeck - Frontend Controller Hotkeys profile if you are playing through ES-DE or Pegasus
  2. How to Select a Steam Input Profile
  3. Open the game, use the Steam Input profile, and click Select + R3
  4. At the top, press Config, and use Screen size, Screen rotation, Screen layout, Screen sizing, and Aspect Ratio to customize your layout
  5. When you are finished playing your game, click Select + R3 again. In the top right, click File, click Quit. If you use the STEAM button to exit out of the game, any changes you have made will not be saved

The Screen layout is where you can find the Hybrid layout option. Here, you can swap to Natural, Vertical, Horizontal, and Hybrid.

How to Reset to EmuDeck Defaults

If you configured the settings and you decide you would like to reset to EmuDeck's defaults, you can do so by following the below:

  1. Open the EmuDeck application in Desktop Mode
  2. Click the Manage Emulators page
  3. Click melonDS and click Reset Configurations

How to Back Up your Screen Layout Configuration

  1. In Desktop Mode, open /home/deck/.var/app/net.kuribo64.melonDS/config/melonDS
    • ~/.var is an invisible folder by default. In Dolphin (file manager), click the hamburger menu in the top right, click Show hidden files to see these folders
  2. Open melonDS.ini in Kate or a text editor of your choice

  3. Copy the following section to another file:

        WindowWidth=1280
    WindowHeight=771
    WindowMax=0
    ScreenRotation=0
    ScreenGap=0
    ScreenLayout=3
    ScreenSwap=0
    ScreenSizing=3
    IntegerScaling=0
    ScreenAspectTop=4
    ScreenAspectBot=4

  4. Back up this file to a secure location. If/when your melonDS configs are reset on an EmuDeck update, you may paste this section into the melonDS.ini to restore your custom layout

How to Roll Back melonDS to an Older Version

If you do not have access to a mouse and keyboard for the below section, use L2 to right click and R2 to left click. Alternatively, remote into your Steam Deck using one of the methods found in the FAQ, How do I remotely control my Steam Deck?.

  1. In Desktop Mode, open Konsole
  2. To see a list of prior versions of the emulator, type:
  3. flatpak remote-info --log flathub net.kuribo64.melonDS
  4. If Konsole prompts you to select system or user, enter 2 to select user
  5. Konsole will list a list of previous versions for the flatpak. The important line for each version is the Commit: line. The Commit: line will have a long accompanying alphanumeric string (the “commit” code). Copy the string for the version you want to downgrade to.
  6. Using Citra as an example:
    • How to Roll Back Flatpaks: 1
  7. To downgrade to the version you want:
  8. flatpak update --commit=put_commit_code_here net.kuribo64.melonDS
  9. Replace put_commit_code_here with the actual code you located in Step 2.
    • Using Citra as an example:
    • How to Roll Back Flatpaks: 2

If the above steps did not work and you are getting an error message along the lines of Flatpak not installed, your Flatpak is likely installed at the system level instead. Select one of the below solutions:

Solution 1: Open the EmuDeck application, click the Manage Emulators page, select the emulator in question, and click Reinstall / Update.

Solution 2: Add sudo in front of the commands written in Step 2 and Step 5. In Step 2, write sudo flatpak remote-info --log flathub net.kuribo64.melonDS and in Step 5, write sudo flatpak update --commit=put_commit_code_here net.kuribo64.melonDS.

How to Configure Language Settings

In-Game

Some games may not have language options. For a full list of which games have language options, download the DS Database from GamesTDB, https://www.gametdb.com/DS/Downloads and open it in a text editor of your choice.

Before proceeding with the below section, you will need to place Nintendo DS BIOS in the Emulation/bios folder.

  1. In Desktop Mode, open melonDS
  2. At the top, click Config
  3. Click Emu settings
  4. Click DS-Mode, check Use external BIOS/firmware files
  5. Close out of the Emu settings window
  6. Click File, click Boot firmware
  7. Click the DS icon at the bottom of the screen
  8. Click the gear icon
  9. Click the globe icon
  10. Select your preferred language