Flycast Guide
MewLew
Supported ROM Formats
Flycast supports the following game formats:
- SEGA Dreamcast Titles:
.cdi,.gdi,.chd,.cue(includes Windows CE games) - SEGA NAOMI GD-ROM Titles:
.7z,.zip,.dat/.lst,.chd - SEGA NAOMI 1 & 2 Titles:
.zip,.7z,.dat/.lst - Sammy Atomiswave Titles:
.zip,.7z
Note: Flycast does not support Hikaru or SEGA System SP games.
Installing Flycast on Xbox Dev Mode
- Prepare Files:
- Get the Flycast
.appxfile (e.g.,flycast_2.5.appx). - (Optional) Get a Dreamcast BIOS (dc_boot) file for better compatibility.
- Get the Flycast
- Upload BIOS to USB (optional but recommended):
- Create a
Sega - Dreamcastgames folder on your USB. - Place the BIOS file and Dreamcast games inside.
- Create a
- Install Flycast:
- Enable Xbox Device Portal in your Xbox Dev Mode settings.
- On your PC, open a web browser and enter the Xbox Device Portal URL.
- Go to My games & apps → Add.
- Drag and drop the Flycast
.appxfile, click Next, then Start. - Once installed, click Done.
- Change App to Game Mode:
- On Xbox, hover over Flycast → press Select → View Details.
- Change it from App to Game.
Internal Storage Setup
Where to upload your ROMs:
- Xbox Device Portal → File explorer →
LocalAppData\Flycast\LocalState- Create a
gamesfolder here. - Upload Dreamcast ROMs.
- You can upload
.zipfiles — the portal will prompt you to unzip.
- Create a
For cheats, VMUs, etc.:
- Upload to:
LocalAppData\Flycast\LocalState\Data
Initial Configuration
- Launch Flycast.
- Go to Settings → Content Location → Add.
- Press Up on the D-pad → A → keep pressing A on .. (Parent Directory) until you see drives.
- Select the E:/ drive (USB)
- If using internal storage the default drive will be Q:/.
- Press B → Select Current Directory.
Recommended Video Settings
- Transparent Sorting: Per Pixel
- Automatic Frame Skipping: Leave default
- Widescreen Mode: Enable if desired
- Filtering: 16x
- VSync: Enable if needed
- Show FPS Counter / VMU in-game: Optional
- Internal Resolution: Max for Series X; reduce on Series S for best performance