We will now write an application that leverages the photoresistor and uses it to control the motor. There are a few concepts that we will cover quickly before we write the application, in order to provide you with better understanding of how our software works.
Pulse width modulation (PWM) is a method that leverages the digital pins to create an analog result. If a digital pin is switched on, it has a value of 5V, and if switched off, it has a value of 0V. PWM allows us to simulate a value between these two ends.
Using our software, we can create what is known as a square wave. This method involves switching a pin on and off to create a signal to the device connected to the digital pin. In our project, it's a DC motor. Therefore, varying the modulation (that is, changing the number of milliseconds that the pin is switched off versus on) will result in a change of speed of the DC motor.
In order to create PWM in our application, we will need...
