Linking a Johnny 5 Tessel kit LCD screen up to the heart rate sensor

heartbeat-lcd.js

var five = require("johnny-five");
var Tessel = require("tessel-io");
var tessel = require('tessel');

var board = new five.Board({
  io: new Tessel()
});
var pin = tessel.port.B.pin[2];
var startTime = new Date().getTime()
var high = true
var beats = 0

board.on("ready", () => {
  var lcd = new five.LCD({
    pins: ["a2", "a3", "a4", "a5", "a6", "a7"]
  });

  // lcd.cursor(0, 0).print("hello world");
  // lcd.cursor(1, 0).print("this is LAAAAA");

  setInterval(function () {
  	console.log("interval")
	pin.analogRead(function(error, value) {
		var time = (new Date().getTime() - startTime) / 1000
		var bpm = Math.round(beats / time * 60)
		console.log(time)
		lcd.cursor(0,0).print(value.toString())
		lcd.cursor(1,0).print(bpm.toString() + " BPM")
		// lcd.cursor(1,0).print(beats)

		if (value < 2.5 && high) {
			high = false
			beats += 1
		}
		else if (value > 2.5 && !high) {
			high = true
		}
	});
  }, 100)
});