System Requirements

Operating system Windows 7+ 64-bit, macOS 64-bit or Linux 64-bit
Processor x86_64 compatible with AVX2 or SSE2 support
Memory 512 MB RAM
Graphics OpenGL 3.3 support


There is no installation process for redream - download it, extract it to a folder and run. If you've upgraded and have a license, download and place it in the same directory before running.

Redream is built to be portable, all of the files used by it are stored alongside it in the same directory. The most important of these files are:

License (optional) redream.key
Boot ROM (optional) boot.bin
Flash ROM flash.bin
Config redream.cfg
Saves vmu0.bin

Dreamcast BIOS

The Dreamcast shipped with a BIOS which provided additional code to help games interact with the Dreamcast hardware.

By default, redream will attempt to emulate the functionality provided by the original BIOS. However, this process is not yet perfect. There are a few issues in the issue queue tracking games that have issues with our BIOS replacement.

If you would like to use the original BIOS instead of our replacement, name it boot.bin and place it in the same directory as redream.

Loading a game

Games can be loaded and ran either through the UI, or directly from the command line.

Through the UI

Go to Options -> Library -> Add Directory to add a directory containing valid game(s) to the library. After doing so, each game should be available from the main menu:

Games list

Through the command line

For quick testing, it's often desirable to run a game directly from the command line by passing it as the first argument to redream:

redream /path/to/game

Managing controllers

Controller input in redream can come from either a connected controller or the keyboard.


Redream relies on SDL's controller database to automatically configure most controllers. You can view information on each connected controller in Options -> Controller info.

If your controller does not exist in SDL's database, there is currently no way to manually configure it.

Keyboard Binds

The default keyboard binds in redream are:

A button L
B button P
X button K
Y button O
START button Space
Joystick -Y axis W
Joystick +Y axis S
Joystick -X axis A
Joystick +X axis D
DPAD Right H
Left trigger [
Right trigger ]

These binds can be managed in Options -> Keyboard binds: Keyboard options

To change a button's bind, select the button, and then press the key you would like it mapped to.

Video options

Video options can be managed in Options -> Video.

Video options


Enable to make the window fill up the entire screen.

Aspect ratio

The Dreamcast output video with a 4:3 aspect ratio, causing black bars to be rendered on the sides when using a modern widescreen display. If you'd like to eliminate these black bars, change this to stretch in order to make the video stretch to fit the window.

Internal Resolution

The Dreamcast originally rendered at either 320x240 or 640x480. Use this option to crank up the detail and render at much higher resolutions.

Save Games

Each connected controller has an associated VMU which can be saved to ingame, just as they would be on the real Dreamcast.