Fade an LED Up and Down

Code

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/* Fade up one of Buzz's LED eyes from 0-255 brightness and then back down to 0 brightness*/ void setup(){ pinMode(3,OUTPUT); //LED on an analogWrite pin. Pins 3,5,6, & 9 can use analogWrite } void loop(){ /*create a 'counter' variable with a starting value of 0 and, as long as the variable is less than 256, run the code between the curly braces, then increase the value of the 'i' variable by 1 */ for(int i = 0; i < 256; i++){ analogWrite(3,i); //use the value of 'i' to set the brightness of LED 3 delay(25); //wait 25 milliseconds (0.025 seconds) before running the 'for' loop again } /*create a 'counter' variable with a starting value of 255 and, as long as the variable is greater than 0, run the code between the curly braces, then decrease the 'i' variable value by 1*/ for(int i = 255; i > 0; i--){ analogWrite(3,i); //use the value of 'i' to set the brightness of LED 3 delay(25); //wait 25 milliseconds (0.025 seconds) before running the 'for' loop again } //Once the 'for' loops have ended, the void loop will start over, running the 'for' loops again } // (c) 2023 Let's Start Coding. License: www.letsstartcoding.com/bsdlicense
 

Walkthrough Video

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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?