Title screen from the MSX2 version of Snatcher

Snatcher title screen on MSX2, used to illustrate software for a computer family openMSX emulates. Image credited to Konami via Wikimedia Commons (public-domain label on the source page); this is not an openMSX capture.

openMSX

MSX COMPUTER EMULATOR

openMSX

openMSX — a long-running, open-source MSX-family emulator with extensive machine profiles, device models, and a detailed manual. Cross-platform binaries and source are published by the openMSX project; active development and issue reporting occur on the project's GitHub.

Jump to download ↓Jump to setup guide ↓

MSXPRIMARY SYSTEM

2000sPROJECT BEGAN

Open sourcePROJECT MODEL

WHY IT MATTERS

Why openMSX

Focused on accuracy and configurability for MSX, MSX2, MSX2+, MSX TurboR and related systems. Provides many machine XML profiles, modular hardware extensions, and a scriptable console for detailed emulation and automation. Documentation and manuals are maintained by the project.

BEST FOR

Best for

Users who want accurate MSX hardware models, scripted setups, and the ability to build from source or use official binaries across Windows, macOS and Linux.

Gameplay from Knightmare on MSX.

The people behind openMSX

History & current status

openMSX is a mature project with roots in the 2000s and an active upstream presence on the project's website and GitHub. The project publishes documentation including a setup guide, user manual, and a command reference. Development, binary/nightly builds, and issue tracking are coordinated via the openMSX GitHub repository and the official site. For current release binaries, build instructions, or to check the latest development status, consult the project's download and repository pages.

What openMSX supports

MSX
MSX2
MSX2+
MSX TurboR
SpectraVideo SVI318/328 (partial)
ColecoVision (via expansion targets visible in project documentation on site/GitHub?)

Download and availability

OFFICIAL DOWNLOADS

Get openMSX

Official binaries and source code are distributed from the openMSX website and the project's GitHub repository. The openMSX site provides links to releases and nightly builds; the GitHub repository hosts source, issues, and build instructions. Use the official site or GitHub to obtain the most recent supported binary for your platform.

Get openMSX ↗

DOCUMENTATION

Official documentation

Read the official configuration, compatibility, and troubleshooting material before changing advanced options.

Read official documentation ↗

Broken or missing download? Emulator projects move and official links sometimes change. Please contact Retro Replay so the source can be verified and updated.

openMSX setup guide

Setup note: This setup guide covers obtaining openMSX, installing official binaries (or building from source), placing required machine ROMs and software, configuring common devices (disk, cartridge, extensions), and launching a machine profile. It references the official manuals and the openMSX GitHub for repository-specific build steps and issue tracking.

1) Decide: binary or build from source: If you prefer convenience, download the official binary for your OS from the openMSX website (see project's Downloads). If you want the latest changes, clone the GitHub repository and follow the project's Compilation Guide in the manuals to build from source. The manuals include a compilation guide and platform notes.
2) Install the binary or build: For binaries: unpack or run installer and place the openMSX program where you normally install applications. For source: clone the openMSX GitHub repository and follow the Compilation Guide in the project's manual. The project's console manpage and manual describe available command-line options.
3) Provide ROMs and software (not included): openMSX does not include commercial game ROMs or proprietary BIOS/firmware. To emulate specific machines you will need the appropriate ROMs or C-BIOS alternatives where supported; consult the setup guide and machine XML entries in share/machines for which ROMs a machine configuration expects. Place user software and ROMs in the dedicated share/roms or persistent/roms folder as described in the manual.
4) Choose or create a machine profile: openMSX ships many machine XML profiles in its share/machines directory. Use the GUI, the -machine command-line option, or the console command 'machine' to select a machine. The Setup Guide explains how to start a machine and how profiles map to ROMs and extensions.
5) Configure disks, cartridges, and extensions: Use the GUI menus or console commands to attach disk images (.dsk), cassette files (.cas), cartridge ROMs, and to enable extensions such as MSX-AUDIO or Moonsound if supported by the chosen machine. The Disk Manipulator tool (documented in the manual) can create and modify disk images and copy files into them.
6) Use the built-in console and scripts: openMSX features a built-in console for fine-grained control. Startup commands can be placed in scripts under share/scripts so openMSX executes them at launch. The Console Command Reference documents commands and settings.
7) Troubleshoot and report issues: If you encounter problems, consult the FAQ and User's Manual on the project site. For bugs or feature requests, open an issue on the openMSX GitHub repository and include logs and the machine profile used.

Software reminder: openMSX does not include commercial games, proprietary BIOS/firmware, or other copyrighted ROMs. Obtain those files legally; consult the manual and machine XML files to determine which files are required for a given machine configuration.