A JavaScript NES emulator.
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dependabot-bot and bfirsh Bump sinon from 7.1.1 to 7.2.2
Bumps [sinon](https://github.com/sinonjs/sinon) from 7.1.1 to 7.2.2.
- [Release notes](https://github.com/sinonjs/sinon/releases)
- [Changelog](https://github.com/sinonjs/sinon/blob/master/CHANGELOG.md)
- [Commits](sinonjs/sinon@v7.1.1...v7.2.2)

Signed-off-by: dependabot[bot] <support@dependabot.com>
Latest commit 8cb9c86 Dec 12, 2018



A JavaScript NES emulator.

It's a library that works in both the browser and Node.js. The browser UI is available at https://github.com/bfirsh/jsnes-web.


For Node.js or Webpack:

$ npm install jsnes

(Or yarn add jsnes.)

In the browser, you can use unpkg:

<script type="text/javascript" src="https://unpkg.com/jsnes/dist/jsnes.min.js"></script>


// Initialize and set up outputs
var nes = new jsnes.NES({
  onFrame: function(frameBuffer) {
    // ... write frameBuffer to screen
  onAudioSample: function(left, right) {
    // ... play audio sample

// Read ROM data from disk (using Node.js APIs, for the sake of this example)
const fs = require('fs');
var romData = fs.readFileSync('path/to/rom.nes', {encoding: 'binary'});

// Load ROM data as a string or byte array

// Run frames at 60 fps, or as fast as you can.
// You are responsible for reliable timing as best you can on your platform.
// ...

// Hook up whatever input device you have to the controller.
nes.buttonDown(1, jsnes.Controller.BUTTON_A);
nes.buttonUp(1, jsnes.Controller.BUTTON_A);
// ...


To build a distribution:

$ yarn run build

This will create dist/jsnes.min.js.

Running tests

$ yarn test

## Embedding JSNES in a web page

You can use JSNES to embed a playable version of a ROM in a web page. This is handy if you are a homebrew ROM developer and want to put a playable version of your ROM on its web page. An example is in the example/ directory.

For a more complex example, see jsnes-web, a web UI written in React.

A potential improvement (hello contributors!) would be to make the React components in jsnes-web reusable so you could use them to embed a single ROM in a web page.

Formatting code

All code must conform to Prettier formatting. The test suite won't pass unless it does.

To automatically format all your code, run:

$ yarn run format