YouTube View Counter

You'll Need

• An Espruino WiFi
• A MAX7219 32x8 Pixel LED display

Wiring Up

Just connect as follows:

Note: Due to the ordering of the wires on the MAX7219 board and the colouring of the supplied ribbon cable, be really careful not to accidentally connect up the voltage backwards.

The MAX7219 board should run off of 3.3v or 5v. 5v will be brighter and will put less strain on the 3.3v line (also used by WiFi).

Since we're using software SPI here, you can use any available GPIO pins for the MAX7219.

Software

Use this software on the right-hand side of the Web IDE, making sure you change the WiFi, Video and API key details at the top. See the video for how to get a working API key.

var WIFI_NAME = "espruino";
var WIFI_OPTIONS = { password : "testtest" };
var VIDEO_ID = "aZ4MKhqvz2w";
var API_KEY = "";

var disp;
var g = Graphics.createArrayBuffer(32, 8, 1);
g.flip = function() { disp.raw(g.buffer); };

require("Font4x8Numeric").add(Graphics);
g.setFont4x8Numeric();

var wifi;

var count = 0;
var lastCount = 0;
var interval;

function drawCount() {
  g.clear();
  var c = count.toString();
  g.drawString(c, g.getWidth()-g.stringWidth(c));
  g.flip();
}

function updateCount(newCount) {
  if (interval) clearInterval(interval);
  interval = undefined;
  var diff = newCount - lastCount;
  if (lastCount===0 || diff<=0) {
    lastCount = newCount;
    count = newCount;
    drawCount();
    return;
  }
  lastCount = count;
  count = newCount;
  drawCount();
  interval = setInterval(function() {
    count++;
    drawCount();
  }, 60000/diff);
}

function getPage() {
  require("http").get("https://www.googleapis.com/youtube/v3/videos?part=statistics&id="+VIDEO_ID+"&key="+API_KEY, function(res) {
    var data = "";
    res.on('data', function(d) { data += d; });
    res.on('close', function() {
      var json = JSON.parse(data);
      updateCount(json.items[0].statistics.viewCount);
    });
  });
}

function onInit() {
  var spi = new SPI();
  spi.setup({ mosi:B3, sck:B5 });
  disp = require("MAX7219").connect(spi, B4, 4);

  wifi = require("EspruinoWiFi");
  wifi.connect(WIFI_NAME, WIFI_OPTIONS, function(err) {
    if (err) {
      console.log("Connection error: "+err);
      return;
    }
    console.log("Connected!");
    // Update immediately
    getPage();
    // Now update every 60 seconds
    setInterval(getPage, 60000);
  });
}

Note: This code uses a 4x8 font (mentioned in the video, but not shown) which will allow you to get more digits (8) on the display.