A JavaScript NES emulator for debugging and disassembling.

Based on JSNES, with a vanilla JS fork of the browser UI merged into it.

The primary focus of this fork is debugging and disassembly. It exposes a variety of tools for generating CPU traces, coverage data, watches and breakpoints, etc. I've also added support for battery saves, gamepads, and recording "movies".

The emulator works on a "bring your own ROM" basis: ROMs, save files, etc, are all stored in IndexedDB (which should allow up to 50MB). ROMs must be loaded into the webapp (via the ^ button in the top-right corner of the "Select a ROM" dialog) before playing, but should remain available indefinitely without re-browsing the hard drive every time.

Since no special server is needed, it works directly from GitHub pages: http://shicks.github.io/jsnesx. Only modern browsers are supported, and only latest Chrome has been tested.