This playground was created for Apple's WWDC Scholarship Program 2018. It emulates the functionality of the Chip8 virtual CPU and includes several public domain ROMs for demo purposes (see the source code for more information). It runs on macOS.
This was my first time implementing an emulator as well as my first time using Swift. While perhaps not the best example of Swift coding style or efficient emulator architecture, the source code should be relatively understandable even to those without much Swift experience. Furthermore, Playgrounds allows users to poke at CPU internals like register state, memory state, and current opcode in real time, which may be helpful.
Chip8-emu running a Connect4 ROM