fixNES vs Nestopia Undead Edition

fixNES is a free, open-source NES emulator for Windows and Linux. It runs NTSC and PAL .nes ROMs and creates .sav files for games that support saving. FDS and QD titles can run when a FDS BIOS named disksys.rom is placed in the same folder, and NSF music files are supported with track changes on the left and right keys. Files can be opened by drag and drop, command-line argument or from ZIP archives. The project lists support for NES mappers and VRC6, VRC7, FDS, MMC5, N163 and Sunsoft 5B audio expansions. Controls are keyboard-only; Windows users can use joy2key for controller input. The standalone build uses supplied scripts and requires freeglut and openal-soft, while a Makefile supports RetroArch core use. The README says the project is not in its most complete or cleanest state. It is licensed under MIT.

Nestopia Undead Edition is a free graphical interface project for the Nestopia emulator, aiming to provide a standalone GUI. The maker’s site lists version 1.99.0 as released, and the project identifies its license as GPL-2.0. The product platform listing names Linux, macOS and Windows, while the supported-platform listing names Windows. The repository includes source required to build the legacy Win32 release; for future GUI work, it points to a cross-platform build under the Jolly Good Emulation project. Nestopia UE supports save states, rewind, netplay, shader support and cheats. For a Nestopia-format cheat database, the project points users to Mighty Mo’s Cheat Code Pack. The project no longer maintains the emulator core and directs core emulation issues upstream. Contributions are reviewed when they relate to standalone GUI builds. Code outside a tagged release is described as volatile, so development work not included in a tagged release may change. The listed plan is free, with no stated price or usage limits.