Rainbow

Rainbow is a closed source emulator for the Atari 5200 and Atari’s 8-bit computers, developed by Chris Lam. Development has ended and the developer’s website is gone, but Rainbow left a strong legacy.

It was the first Atari 5200 emulator to be ported to the Mac, a port made by Richard Bannister.

Rainbow ran the vast majority of official Atari 5200 software, and usually only struggled with games and programs that used undocumented features. Unlike many modern Atari 5200 emulators, it is not cycle accurate, so it does not reproduce the most obscure behaviour of the hardware.

Rainbow also included debugging tools for anyone interested in how the Atari 5200 works, with trace tools for viewing internal chip states and following 6502 execution.

The Mac version is based on an older release, because version 2.1 was a complete rewrite of the emulator. It should still offer reasonable compatibility and speed.