Turn Knob Sets LED Strip Brightness

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.


/* Use the turn knob to control the brightness of the LED strip */ #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(A0,INPUT); //turn knob } void loop() { int brightness = analogRead(A0)/10 ; //Create a variable called 'brightness' that is an integer (whole number) //The brightness variable value takes the reading from the turn knob and divides it by 10, so it has a range of 0 to 102 strip.setPixel(strip.ALL,200,brightness); //set all pixels to a color value of 200 and a brightness value of 'brightness' variable. strip.draw(); //send the setPixel data to the strip } // (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.

  • Your turn knob is connected to port A0, not A2 as the video says.

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

Challenges

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Concepts

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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?




2. Which syntax ends a single code command?