High Quality Content by WIKIPEDIA articles! DGen is a Sega Genesis (Mega Drive) emulator. It runs on many operating systems including Microsoft Windows and Linux. It is open source software licensed under the BSD License. DGen/SDL is the version that uses Simple DirectMedia Layer. Dgen and DGen/SDL are no longer maintained for the first four operating systems listed at right, but are maintained by Syn-Z for PlayStation Portable 1.5.