LED Strip Clapper

Code

The code in the editor below is ready to run! Plug your Code Lab in to your computer's USB port with the cable and hit 'Upload Your Code!' to see what it does. Change something in the code, like a delay or pin number. Try to add something new to the program - it's yours to tinker with! You can always press the 'Restore' button to return the code to the working example.

/* Clap light that turns on the entire LED strip when the sound trigger 'hears' a clap, then turns off the strip when it 'hears' another clap */ #include "LEDStrip.h" //The LEDStrip.h library gives your code access to special functions exclusive to the LED Strip LEDStrip strip = LEDStrip(50, 13, 12); //Set up the strip by defining how many pixels (50) and which pins of the microchip are used (always 13 and 12 on Code Lab) int clapCount = 0; //create a variable named clapCount that is an integer (whole number) with starting value of 0 void setup() { pinMode(A3,INPUT); //sound trigger } void loop() { if(analogRead(A3) > 600){ //if the sound reading is greater than 600 clapCount++; //increase the value of clapCount by 1 } if(clapCount == 1){ //if clapCount equals 1 strip.setPixel(strip.ALL,200); //set all the pixels to a color value of 200 strip.draw(); //send the setPixel data to the strip } else{ //Otherwise, if clapCount is anything other than 1 clapCount = 0; //set clapCount to 0 strip.clear(); //turn off any pixels that are lit on the strip strip.draw(); //send that 'clear' command to the LED strip } } /*Note: To test if this is working, lightly tap the sound trigger. You may need to change the threshold for clapCount to increase, depending on how noisy your environment is. */ // (c) 2021 Let's Start Coding. License: www.letsstartcoding.com/bsdlicense

Walkthrough Video

Watch the video for a line-by-line explanation of how the example program works. Then you'll be ready to make some changes of your own!

Video Notes for Code Lab Users:

You will use “50” instead of “15” as the first argument in your LEDStrip function.
The second and third arguments of the LEDStrip function (13 and 12) do not need to change. These connections are permanently set on Code Lab.

Use this spectrum to estimate the color values you'll need for your 'setPixel' arguments to achieve your favorite color!

Challenges

Can you complete the challenges? Change the code in your code editor above. Upload your code to see the effect when you're finished. Complete a challenge? Check it off the list!

Update the threshold number next to the ‘>’ sign in the code to adjust the sensitivity of the program to sound. If you’re in a noisy environment, the threshold should be higher. In a quiet environment, the threshold can be lower.

Tip: to test if the sound sensor is working, tap it lightly. This should trigger the LED strip to change.

Change the color of the LED strip by changing the second argument in the setPixel function.

Tough challenge: add an ‘else if’ statement between the ‘if’ statement and the ‘else’ statement that changes the color of the LED strip if clapCount == 2. Using this pattern, you could make the LED strip change colors over and over as it ‘hears’ more sound.

Concepts

These are the new code concepts covered in this example program. To become a great coder, read through these concepts to learn new vocabulary.

Quiz

If you're having trouble, try to run an experimental program or look at the example code to help you find the answer.

1. Which syntax ends the entire 'void loop' function?

semicolon ;
parentheses )
closing curly brace }

2. Which syntax ends a single code command?

semicolon ;
closing curly brace }
period .

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