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Exercise 2.1 - Lights and Buttons

a) Light up the LED

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

Press the button to light the LED in green.

Enter a color's RGB code to make the LED light up that color!

script.js

This is the JavaScript code behind the above application.

/* global writeLog, getInput, tf */
writeLog("Solution for exercise 2.1 a) Light up the LED");
// Create a global variable to store the found devices
var devices;
var led;
// 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);
}
function green() {
 // Set the LED to green
 led.setColor(0, 255, 0);
 writeLog("LED should now be green!")
}
function setColor() {
 // Get the value from the color's input field
 var hex = getInput("hexColor");
// Remove the hashtag if present
 hex = hex.replace("#", "");
 var rgb = [(x = parseInt(hex, 16)) >> 16 & 255, x >> 8 & 255, x & 255];
// Set the color of the LED
 led.setColor(rgb[0], rgb[1], rgb[2]);
writeLog("I set the color to R = " + rgb[0] + ", G = " + rgb[1] + ", B = " + rgb[2]);
}