/* Variable Brightness LEDs
*  Done with three of Arduino's Pulse Width Modulation (PWM)
*  pins (9,10,11)
*/

// Set three pin variables for the three PWM pins
int pwmPin1 = 11;
int pwmPin2 = 10;
int pwmPin3 = 9;
// Set a variable for the intial value for the PWM
int pwmVal1 = 0;
int pwmVal2 = 0;
int pwmVal3 = 0;

// Setup
// Set PWM pins to OUTPUT
void setup() 
{
  pinMode(pwmPin1, OUTPUT);
  pinMode(pwmPin2, OUTPUT);
  pinMode(pwmPin3, OUTPUT);
}

// Loop
void loop() 
{
  // analogWrite's range runs from 0 to 255, so when any of 
  // our values reaches maximum, reset it to 0
  if(pwmVal1 >= 255) {
    pwmVal1 = 0;
  }
  if(pwmVal2 >= 255) {
    pwmVal2 = 0;
  }
  if(pwmVal3 >= 255) {
    pwmVal3 = 0;
  }
  // Set the first PWM pin to pwmVal1
  analogWrite(pwmPin1,pwmVal1);
  // Increment pwmVal1 by 1
  pwmVal1=pwmVal1+1;
  // Same as before...
  analogWrite(pwmPin2,pwmVal2);
  // ... but increment pwmVal2 by 5 instead of 1
  pwmVal2=pwmVal2+5;
  // Same as before...
  analogWrite(pwmPin3,pwmVal3);
  // ... but increment pwmVal3 by 10 instead of 1 or 5
  pwmVal3=pwmVal3+10;
  // Put in a short delay to see the effect
  delay(10);
}