Introducing the Piezo Buzzer
The buzzer is a small component with a piece of metal in it that moves when you apply a voltage
across it. This motion causes a small sound, or “click.”
If you turn the voltage on and off fast enough, you get different beeps, squeals, chirps and buzzes.
You will use PWM to control the speed of turning the piezo on and off — and, in turn, the audio
frequency coming out of the buzzer. Adjusting the PWM enables you to get legitimate notes out of
the buzzer.
If you flip the buzzer over and look at the bottom, you will see that one pin has a (+) next to it. That
pin gets connected to a signal from the P0 pin. The other pin should be connected to ground.
Hardware Hookup
Ready to start hooking everything up? Check out the wiring diagram below to see how everything is
connected.