Developing an LED night lamp

So now we have developed our mood lamp, but it will turn on only when we connect a power supply to Arduino. It won't turn on or off depending on the darkness of the environment. Also, to turn it off, we have to disconnect our power supply from Arduino. In this section, we will learn how to use switches with Arduino.

Introduction to switch

Switches are one of the most elementary and easy-to-overlook components. Switches do only one thing: either they open a circuit or short circuit. Mainly, there are two types of switches:

• Momentary switches: Momentary switches are those switches which require continuous actuation—like a keyboard switch and reset button on the Arduino board

• Maintained switches: Maintained switches are those switches which, once actuated, remain actuated—like a wall switch.

Normally, all the switches are NO (normally opened) type switches. So, when the switch is actuated, it closes the path and acts as a perfect piece of conducting wire. Apart from...