old_contents: 'use strict';
  
  var ev3 = require('../index');
  
  ev3.button.enter.on('press', function () {
      console.log('Up button pressed!');
  
      console.log('Battery voltage: ' + ev3.battery.getVoltage());
  });
  
  ev3.button.enter.on('release', function () {
      console.log('Up button released!');
  });
  
new_contents: 'use strict';
  
  var ev3 = require('../index');
  
  console.log('ev3 started...');
  
  ev3.button.up.on('press', function () {
      console.log('up button pressed!');
  });
  
  ev3.button.enter.on('press', function () {
      console.log('enter button pressed!');
  
      console.log('battery voltage: ' + ev3.battery.getVoltage());
  });
  
  ev3.button.down.on('press', function () {
      console.log('down button pressed!');
  });
  
  ev3.button.right.on('press', function () {
      console.log('right button pressed!');
  });
  
  ev3.button.left.on('press', function () {
      console.log('left button pressed!');
  });
  
  ev3.button.escape.on('press', function () {
      console.log('escape button pressed!');
  
      process.exit();
  });
  
subject: Update ev3.js