(Arduino Study) LED brightness changing, using analog pin-port, (analogWrite function)

'analogWrite' output value's range is 0~255.

In the source code, 'i' is changed 0 to 255 and 255 to 0.

So LED brightness would be changed.

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const int LED = 9;
int i=0;

void setup(){
  pinMode(LED, OUTPUT);
}

void loop(){
  
  for(i=0; i< 255; i++){
    analogWrite(LED, i);
    delay(10);
  }
  
  for(i=255; i> 0; --i)
  {
    analogWrite(LED, i);
    delay(10);
  }
}

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