Sega Dreamcast¶

Play Dreamcast games, plus the Sega NAOMI and Sammy Atomiswave arcade games built on the same hardware. They all run on Flycast, from one folder: Roms/Dreamcast (DC)/.

Crazy Taxi 2 on the Fold's cover screen, with the Dreamcast pad: A, B, X and Y in the Dreamcast's colours

Dreamcast gets the same features as the other systems:

the in-game menu with save states and auto-resume
the Game Switcher
play time in the Game Tracker
RetroAchievements for disc games

Dreamcast has no cheats.

BIOS¶

Dreamcast discs need the real BIOS. Put dc_boot.bin in Bios/DC/.

Without it, the game doesn't start and the app says:

Dreamcast needs a BIOS: put dc_boot.bin in Bios/DC/

The arcade games need their own BIOS instead (see NAOMI and Atomiswave). They don't need dc_boot.bin.

File	For
`dc_boot.bin`	Dreamcast discs
`naomi.zip`	NAOMI games
`awbios.zip`	Atomiswave games

Coming from the handheld

The handheld can run Dreamcast discs without a BIOS. The app can't: put dc_boot.bin in Bios/DC/ even if your handheld played the games without it.

Adding games¶

Put Dreamcast discs in Roms/Dreamcast (DC)/. The app plays .chd, .cdi, .gdi, .cue and .m3u. A zip or 7z holding one disc plays too; the app unpacks it on first launch.

A GDI game is a .gdi file plus its track files. Give each GDI game its own folder, and name the .gdi after the folder:

Roms/Dreamcast (DC)/
├── Soulcalibur (USA).chd
└── Shenmue (USA)/
    ├── Shenmue (USA).gdi
    ├── track01.bin
    ├── track02.raw
    └── track03.bin

The folder shows as one game in the list.

Rename a disc.gdi

Some sets name every sheet disc.gdi. The app doesn't list a folder whose .gdi is named differently from the folder. Saves, states and the memory card are named after the file, so every disc.gdi game would share them. Rename the .gdi to match its folder.

A multi-disc game plays as one game from an .m3u that lists its discs. The in-game menu then has a Disc row; see Multi-disc games.

Controls¶

The face buttons map to the Dreamcast pad by the printed letter: A is the Dreamcast's A. The Dreamcast pad is lettered like an Xbox pad:

Position	Dreamcast button
Bottom	`A`
Right	`B`
Left	`X`
Top	`Y`

Control	Dreamcast control
D-pad	D-pad
Left stick	Analog stick
`L2` / `R2`	Analog triggers
`START`	`START`
`SELECT`	Insert a coin (NAOMI and Atomiswave)
`L3` (press the left stick)	Test, the operator menu (NAOMI and Atomiswave)
`R3` (press the right stick)	Service (NAOMI and Atomiswave)

The on-screen pad draws A B X Y in the Dreamcast's colours, in the positions above.
With the on-screen pad, the in-game menu follows the drawn letters: the bottom button (A) confirms and the right one (B) goes back.
On a controller, a "Press A" prompt means the button printed A. If a controller is read wrongly, set Controller Layout in Options → Console Settings (see Controls). On a Nintendo-layout pad, set it to Xbox to play with the Dreamcast's positions instead.
L3 and R3 are on controllers only: the on-screen pad has no stick buttons.
On a controller the triggers press as far as you pull them. On the on-screen pad, L2 and R2 press fully.
MENU, or SELECT + START, opens the in-game menu. On NAOMI and Atomiswave the game sees the SELECT press first, so it may count a coin.

Multiplayer¶

Up to four players can play, each on their own controller; see Local Multiplayer. NAOMI and Atomiswave games take up to four players too. The points below are for Dreamcast discs:

Every player's controller has the Vibration Pack.
Only Player 1's controller has a memory card. Games save to Player 1's card.
To give Players 2 to 4 a card, set Device in Expansion Slot B1, C1 or D1 to VMU in Emulator Settings under Core settings.

Memory cards (VMU)¶

Every game gets its own memory card, kept with your other saves:

Saves/DC/<game>.A1.bin

For example Saves/DC/Soulcalibur (USA).A1.bin. A GDI game's card is named after its folder, and an .m3u game shares one card across its discs.

To give a game a fresh, empty card:

Delete the game's .A1.bin file in Saves/DC/.
Launch the game. It starts with a blank card.

Renaming a ROM

Renaming a ROM leaves its card behind under the old name, as with any save. Rename the card to match.

More detail

The names match the handheld's NX Redux, so you can copy a card between your phone and your handheld.
The arcade games keep their high scores and cabinet settings in Saves/DC/reicast/.

Save states¶

Save states work as on every other system: eight slots, plus the auto-save the app makes when you quit.

A Dreamcast save state is about 36 MB, the console's memory stored as it is. Eight full slots for one game take close to 300 MB on your phone.

Settings¶

Change Dreamcast's settings in Options → Core Options in the in-game menu. You can also set them outside a game, for every game or for one, in Emulator Settings.

The internal resolution starts at 640×480, the Dreamcast's own. Higher values look sharper but cost speed.

NAOMI and Atomiswave¶

NAOMI and Atomiswave games are MAME-style zips (or 7z). To play them:

Put the zips straight into Roms/Dreamcast (DC)/, next to your Dreamcast discs.
Put the board's BIOS zip in Bios/DC/: naomi.zip for NAOMI, awbios.zip for Atomiswave.
Launch the game and press SELECT to insert a coin, then START.

A few sets need another BIOS zip, such as naomi2.zip for NAOMI 2 games. The message names the one that's missing.

Don't rename the zips

Flycast finds a game by its short zip name (mslug6.zip, not Metal Slug 6.zip). The game list still shows readable names: mslug6.zip shows as Metal Slug 6.

More detail

Names. Each zip gets its full title from Flycast's own game list. A Rename Rom or map.txt alias always wins over that title.
BIOS zips are hidden. A BIOS zip put in the game folder by mistake is not listed as a game. It still has to be in Bios/DC/.
Clones. A clone set loads its parent set from the same folder.
Zipped discs. A zip that isn't one of Flycast's arcade sets is treated as a zipped Dreamcast disc and unpacked.
Atomiswave BIOS. Both MAME versions of awbios.zip work.

When a set won't start¶

The app checks the BIOS before launch. When the zip is missing, it says, for example:

Metal Slug 6 needs awbios.zip: put it in Bios/DC/

When the BIOS zip is there but a file in it is missing, it names the file:

‹Game› needs naomi.zip with ‹file› in it: put a complete naomi.zip in Bios/DC/

When the game's own zip is incomplete:

‹Game› needs ‹file›, which ‹set›.zip does not have: the set is incomplete or from another MAME version

Get a complete set that matches Flycast's version of MAME.

RetroAchievements¶

Dreamcast discs use the app's RetroAchievements support, like the other systems. The app recognises .chd, .gdi, .cue and .m3u games, and a zipped disc once it is unpacked.

.cdi games are not recognised.
NAOMI and Atomiswave games are not on RetroAchievements.