This is Mednafen with clean CHD support using https://github.com/rtissera/libchdr

Mednafen is a portable, utilizing OpenGL and SDL, argument(command-line)-driven multi-system emulator. Mednafen has the ability to remap hotkey functions and virtual system inputs to a keyboard, a joystick, or both simultaneously. Save states are supported, as is real-time game rewinding. Screen snapshots may be taken, in the PNG file format, at the press of a button. Mednafen can record audiovisual movies in the QuickTime file format, with several different lossless codecs supported.

The following systems are supported(refer to the emulation module documentation for more details):

• Apple II/II+/IIe/Enhanced IIe
• Atari Lynx
• Neo Geo Pocket (Color)
• WonderSwan
• GameBoy (Color)
• GameBoy Advance
• Nintendo Entertainment System
• Super Nintendo Entertainment System/Super Famicom
• Virtual Boy
• PC Engine/TurboGrafx 16 (CD)
• SuperGrafx
• PC-FX
• Sega Game Gear
• Sega Genesis/Megadrive
• Sega Master System
• Sega Saturn (64-bit only)
• Sony PlayStation

Mednafen is distributed under the terms of the GNU GPLv2.

Due to the threaded model of emulation used in Mednafen, and limitations of SDL, a joystick is preferred over a keyboard to play games, as the joystick will have slightly less latency, although the latency differences may not be perceptible to most people.