bfirsh/jsnes

$ npm install jsnes

<script type="text/javascript" src="https://unpkg.com/jsnes@2/dist/jsnes.min.js"></script>

<div id="nes" style="width: 512px; height: 480px"></div>
<script src="https://unpkg.com/jsnes@2/dist/jsnes.min.js"></script>
<script>
  var browser = new jsnes.Browser({
    container: document.getElementById("nes"),
    onError: function (e) {
      console.error(e);
    },
  });
  jsnes.Browser.loadROMFromURL("my-rom.nes", function (err, data) {
    if (err) {
      console.error(err);
      return;
    }
    browser.loadROM(data);
  });
</script>

var browser = new jsnes.Browser({
  container: document.getElementById("nes"),
  romData: romData,
});

import { Browser } from "jsnes";

function Emulator({ romData }) {
  const containerRef = useRef(null);
  const browserRef = useRef(null);

  useEffect(() => {
    browserRef.current = new Browser({
      container: containerRef.current,
      romData: romData,
    });
    return () => browserRef.current.destroy();
  }, [romData]);

  return <div ref={containerRef} />;
}

// 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
nes.loadROM(romData);

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

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

var nes = new jsnes.NES(options);

var browser = new jsnes.Browser(options);

// Get the current key map
var keys = browser.keyboard.keys;

// Remap Player 1 A button to the J key (keyCode 74)
keys[74] = [1, jsnes.Controller.BUTTON_A, "J"];
browser.keyboard.setKeys(keys);

$ npm run build

$ npm test

$ npm run format