Now that we know our light sensor works, we can add an LED and create our night-light.
Connect the short leg of your LED to a ground rail using a 330K ohm resistor, and wire the long leg to GPIO #5, also known as P1-29:
Create a file in the same folder as the other files from this chapter, and copy the contents of print-light-sensor-readings.js into it.
In the start of the board.on('ready') handler, add a constructor for our LED:
let light = new five.Led('P1-29')And in the lightSensor.on('change') function, replace the console.log statement with the logic that will turn the LED on and off:
if(this.value <= 25) {
light.on()
} else {
light.off()
}And we're ready to run! Load the folder onto your Pi, navigate to the folder in your Pi's SSH session, and run:
sudo node night-light.jsWhen you cover the light sensor with your thumb, the LED should light up, as shown in the following image:
