LED Strip Police Siren

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.

/* Turn the entire LED Strip red, then blue, while playing a tone like a police siren */ #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) void setup() { pinMode(A5,OUTPUT); //Speaker } void loop() { strip.setPixel(strip.All, 100); //use strip.All to set all the pixels one color, then set the color value (100 is red) tone(A5,500); //Play a tone of 500 hertz strip.draw(); //Send the setPixel values to the LED Strip delay(1000); //Wait 1000 milliseconds (1 second) with the tone of 500 playing strip.setPixel(strip.All, 299); //A color value of 299 is blue on the LED strip tone(A5,100); //Play a tone of 100 hertz strip.draw(); //Send the setPixel values to the LED Strip delay(1000); //Wait 1000 milliseconds before restarting the loop } //(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. They 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!

Change the siren colors using the setPixel( ) function.

Change the delays to change how fast the siren toggles back and forth. Which delays make the siren the most realistic? How fast can the code run and still show the siren change color?

Change the tones that the siren plays. What tone values sound the most realistic? What tone values sound like an alien siren?

Add a third siren tone and a third color that shows on the LED strip. Hint: Look for the pattern in the code. There are different 'sections' broken up by blank lines in the void loop.

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.

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