Hello and welcome! My name's Riley. I'm a Grade 12 computer engineering student and this is my final project in which I utilize Arduino Uno to make my own electric light controlled piano. If you have any questions, compliments, or criticisms, feel free to leave them in the comments and I'll try to get back to you with a reply. Anyway, thanks for taking a look at my invention and I hope you enjoy.

Step 1: How/Why It Works

So how it works is; I used LED's and photoresistors to act as strings. So when I move my finger in front of the LED, the photoresistor would realize the drop in light and trigger my speaker. But what note does the speaker play? This is decided when you go into the tuning mode by pressing the right button. Once you're in this mode you will realize that only 1 LED is lit up. This represents the string or note you're tuning. To change this note, you use the joystick. The way this works is the joystick sends its x value to the Arduino and the Arduino turns that value into a pitch value. After you're done choosing the pitch, press the left button to rotate between the notes, setting all 4 to what you want them to be. After the tuning process is complete, press the right button again to switch back to play mode. In addition, it is important to know that the left button, previously used for switching notes, now in play mode, is used to stop the speaker's sound. Also, the potentiometer is used to regulate the speaker's volume.

Step 2: The Circuit

The circuit's pretty simple to understand but it can be easy to make mistakes due to the clutter. Make sure to double check all the wires before running any code because, if it's not working, this is most likely the reason.

P.S. That's not a piezo buzzer, its a speaker.