Sega Dreamcast

• Accepted ROM formats: .cdi, .cue, .gdi, .chd, .m3u
• Folder: /userdata/roms/dreamcast

The “World” BIOS file and USA flash file which should work fine for the massive majority of games.

Alternative BIOS files that are also acceptable:

Dreamcast discs are a special form of CD named GD, which are capable of holding up to 1GB of data, compared to the ~700MB capacity of regular CDs. GDs were traditionally dumped off of the original console as GD-ROMs (which contains a game.gdi sheet, info.txt and data.bin/.iso/.raw track(s)), but some more modern tools may use the more universal game.cue sheet and data.bin track format. Most emulators can load either sheet format fine. You should load the .gdi or .cue sheet and not the .bin/.iso/.raw tracks. From Batocera v31 onwards, EmulationStation should avoid making duplicate entries for these files.

If you're currently missing the .gdi or .cue files, check out the section on recovering them on this page.

The recommended format for compressing disc images is CHD.

If compressing the image into the CHD format ensure that you are using chdman version 0.230 or later, as earlier versions have issues with Dreamcast images. If your compressed ROMs are failing to launch in Batocera, users have reported having more success making chdman target a .gdi file instead of a .cue file. Most online .bat scripts only target .cue files. There is a custom version of chdman that supports rolling to and from CUE/BIN files here.

To automatically load the next disc of a game, you can use a .m3u playlist file. To make one, simply create a text file with the same filename as your intended game name (it could be anything, really). Within that text file, write the names of the .gdi sheets or .chd files for your game discs. For instance, if your game's .gdi sheets were structured like

roms/
└─ dreamcast/
   ├─ Shenmue (Disc 1).gdi
   ├─ Shenmue (Disc 1).bin
   ├─ Shenmue (Disc 2).gdi
   ├─ Shenmue (Disc 2).bin
   ├─ Shenmue (Disc 3).gdi
   ├─ Shenmue (Disc 3).bin
   ├─ Shenmue (Passport disc).gdi
   └─ Shenmue (Passport disc).bin

you would put the following as text into the Shenmue.m3u text file:

Shenmue.m3u

Shenmue (Disc 1).gdi
Shenmue (Disc 2).gdi
Shenmue (Disc 3).gdi
Shenmue (Passport disc).gdi

Save the text file with the file extension .m3u and place it in the dreamcast folder along with the game's discs. When you get to the end of that disc, the next disc will be automatically loaded. In libretro cores, if this fails, you can utilize Retroarch's 'Disc Control' menu in the Quick Menu (Hotkey+) to manually eject a disc and insert another (Swap Disc is for legacy purposes and should not be used). Refer to multi-disc games for more info.

Flycast is a fork of Reicast (which itself is a fork of nullDC). A highly compatible and accurate standalone emulator.

Flycast can also be used to run NAOMI arcade games due to being nearly identical hardware.

Standardized features available to all cores of this emulator: dreamcast.videomode, dreamcast.videomode, dreamcast.bezel, dreamcast.bezel_stretch, dreamcast.hud, dreamcast.bezel.tattoo, dreamcast.bezel.tattoo_corner, dreamcast.bezel.tattoo_file, dreamcast.bezel.resize_tattoo

All other configuration must be done via the flycast-config in the Applications folder ([F1] on the systems screen).

RetroArch has its own page.

A fork of a fork of a fork… this is an identical version of standalone Flycast but inside of a libretro core. Makes use of RetroArch's features.

All other settings can be configured from RetroArch's Quick Menu → Options ([HOTKEY] + ).

Redream is a multi-platform standalone emulator. Has high compatibility with low system requirements. Lacks some options compared to Flycast.

Standardized features available to all cores of this emulator: dreamcast.videomode, dreamcast.bezel, dreamcast.bezel_stretch, dreamcast.hud, dreamcast.bezel.tattoo, dreamcast.bezel.tattoo_corner, dreamcast.bezel.tattoo_file, dreamcast.bezel.resize_tattoo

Redream can also be configured from its redream-config application ([F1] on the system list → Applications).

On PC, Redream locks some of settings behind a one-time purchase of a premium license. Once purchased, this can be downloaded (it's just a text file) from https://redream.io/account after signing in:

Redream checks for its license key in /userdata/system/configs/redream/redream.key. If a valid license is found, additional rendering options (such as rendering resolution) will become unlocked.

Flycast supports custom texture packs for games. To use them:

1. Copy the unzipped texture pack folder to saves/dreamcast/flycast/textures/ (it should already be titled the proper game ID for the game that it supports)
2. In Batocera, launch flycast-config from the file manager → Applications
3. Navigate to Settings → Video and tick “Load Custom Textures”
4. Exit with [Alt] + [F4] and then launch the game from Batocera

Here are the default Sega Dreamcast's controls shown on a Batocera Retropad:

Each Dreamcast emulator handles the [HOTKEY], its chords and the [SELECT] button differently.

• libretro/flycast
  • [HOTKEY] by itself does nothing.
  • [HOTKEY] + [START] closes the emulator.
  • [SELECT] does nothing.
• Flycast standalone
  • [HOTKEY] by itself opens Flycast's quick menu.
  • [HOTKEY] + [START] closes the emulator.
  • [SELECT] does nothing.
• Redream
  • [HOTKEY] by itself opens Redream's menu.
  • [HOTKEY] + [START] does nothing.
  • [SELECT] toggles fast-forward.

For further troubleshooting, refer to the generic support pages.