Building Smart Homes with Raspberry Pi Zero

Testing individual components

As the first project of this chapter, we are simply going to check that each individual component (the sensor and the PowerSwitch tail) are working correctly.

I will now go through the main parts of this first piece of code. It starts by including the DHT sensor module for Node.js:

var sensorLib = require('node-dht-sensor');

Then, we create an object to read data from the sensor, and also initialize it when we start the software:

var sensor = { initialize: function () { return sensorLib.initialize(11, 4); }, read: function () { var readout = sensorLib.read(); console.log('Temperature: ' + readout.temperature.toFixed(2) + 'C, ' + 'humidity: ' + readout.humidity.toFixed(2) + '%'); setTimeout(function () { sensor.read(); ...