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Exercise 2.1 - Lights and Buttons

a) Initialize LEDs on startup

This is the console. All output created with writeLog() is shown here.

On startup, the LED is off and the button's LED is set to white.

script.js

This is the JavaScript code behind the above application.

/* global writeLog, getInput, tf */
writeLog("Solution for exercise 2.1 c) Initialize LEDs on startup");
// Create a global variable to store the found devices
var devices;
var button;
// Initialite connected devices
tf.initDevices(initDone);
// Call this when all connections are established
function initDone(connectedDevices) {
    if (connectedDevices.length === 0) {
        writeLog("Oops, didn't find any devices! Make sure they are connected and refresh this page!");
    // Store the devices on the global variable
    devices = connectedDevices;
    // Get the LED light
    led = devices.getDeviceByIdentifier(271);
    // Get the LED button
    button = devices.getDeviceByIdentifier(282);
    // Turn the LED off initially
    led.off();
    // Set the button's LED to white
    button.white();
    writeLog("LED is off and button is white!")

	/* global writeLog, getInput, tf */
	writeLog("Solution for exercise 2.1 c) Initialize LEDs on startup");

	// Create a global variable to store the found devices
	var devices;
	var led;
	var button;

	// Initialite connected devices
	tf.initDevices(initDone);

	// Call this when all connections are established
	function initDone(connectedDevices) {

	if (connectedDevices.length === 0) {
	writeLog("Oops, didn't find any devices! Make sure they are connected and refresh this page!");
	}

	// Store the devices on the global variable
	devices = connectedDevices;

	// Get the LED light
	led = devices.getDeviceByIdentifier(271);

	// Get the LED button
	button = devices.getDeviceByIdentifier(282);

	// Turn the LED off initially
	led.off();

	// Set the button's LED to white
	button.white();

	writeLog("LED is off and button is white!")
	}