The NeopenBios is an open source alternative bios for MVS and AES system.
The goal is to provide the best features for the gamers and the developers.
It is currently developed by ElBarto and Furrtek, a lot of features were suggested by the Neo-Geo community.
The bios is under heavy development right now and the first step before adding cool features is to achieve the best compatibility with all the games.

Presentation at the RGC, in french only sorry

You can download the first beta of v0.1 here

Instruction for building

You can download the source using CVS (Windows users can use TortoiseCVS).
The cvs server is, the path is /cvs, the user is anoncvs and the module is neopenbios.
You'll need a build of gcc, you can either build one yourself, use the toolchain Makefile (in the cvs, module toolchain) or simply download this pre-build gcc for windows