In the article below, the topic of OpenMSX will be addressed from a broad and detailed perspective. OpenMSX is a topic of great relevance in today's society, which has sparked numerous debates and controversies in different areas. Over the last decades, OpenMSX has gained special importance and has been the subject of studies and research by experts in the field. In this article, various aspects related to OpenMSX will be explored, such as its origin, evolution, impact on society, and possible solutions or alternatives to deal with it. In addition, different approaches and points of view on OpenMSX will be analyzed, in order to offer a complete and enriching vision of this topic that is so relevant today.
| openMSX | |
|---|---|
| Developer | openMSX Team |
| Stable release | 21.0
/ September 26, 2025[1] |
| Repository | |
| Written in | C++ (core), Tcl, (openmsx-catapult: wxWidgets)[2] |
| Operating system | POSIX and Windows |
| Type | Emulator |
| License | GNU GPLv2 |
| Website | openmsx |

openMSX is a free software emulator for the MSX architecture. It is available for multiple platforms, including Microsoft Windows and POSIX systems such as Linux.
For copyright reasons, the emulator cannot be distributed with original MSX-BIOS ROM images. Instead, openMSX includes C-BIOS, a minimal implementation of the MSX BIOS, allowing some games to be played without the original ROM image. It is possible for the user to replace C-BIOS by native BIOS if they prefer.
openMSX emulates a large amount of MSX systems and MSX-related hardware, including:
openMSX also emulates the SV-318/SV-328 computers, the ColecoVision and the Sega SG-1000.
Notable features include:
openMSX has an open communication protocol to communicate with the openMSX emulator. Utilizing this communication protocol enables to write versatile add-ons for openMSX. Projects making use of this protocol include the following applications:
There is a dead subproject to redevelop Catapult, a GUI developed for the emulator that is part of the project, utilizing Python and the Qt toolkit.
The separate openMSX Debugger, written in C++ and utilizing the Qt Toolkit is not in development anymore, as efforts are now focused on the built-in debugger.
As of release 20.0, a GUI was integrated that replaces almost all functionality of the Catapult and separate Debugger programs. Both these sub-projects will not be developed further, in favour of the built-in functionality. The new GUI uses the Dear ImGUI toolkit.