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/*
  Mega analogWrite() test

  This sketch fades LEDs up and down one at a time on digital pins 2 through 13.
  This sketch was written for the Arduino Mega, and will not work on other boards.

  The circuit:
  - LEDs attached from pins 2 through 13 to ground.

  created 8 Feb 2009
  by Tom Igoe

  This example code is in the public domain.

  https://www.arduino.cc/en/Tutorial/BuiltInExamples/AnalogWriteMega
*/

// These constants won't change. They're used to give names to the pins used:
const int lowestPin = 2;
const int highestPin = 13;
 

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void setup() {
  // set pins 2 through 13 as outputs:
  for (int thisPin = lowestPin; thisPin <= highestPin; thisPin++) {
    pinMode(thisPin, OUTPUT);
  }
}
 

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void loop() {
  // iterate over the pins:
  for (int thisPin = lowestPin; thisPin <= highestPin; thisPin++) {
    // fade the LED on thisPin from off to brightest:
    for (int brightness = 0; brightness < 255; brightness++) {
      analogWrite(thisPin, brightness);
      delay(2);
    }
    // fade the LED on thisPin from brightest to off:
    for (int brightness = 255; brightness >= 0; brightness--) {
      analogWrite(thisPin, brightness);
      delay(2);
    }
    // pause between LEDs:
    delay(100);
  }
}