HOW LED FADE

HOW LED  FADE

In this blog we discuss how LED brightness change or we can say intensities change.......This example demonstrates the use

of the analogWrite() function in fading an LED off and on. AnalogWrite uses pulse width modulation (PWM), turning a digital pin on and off very quickly with different ratio between on and off, to create a fading effect.

Things Required:

• Arduino
• Breadboard
• LED
• Resistor(220ohm)
• jumper wire

CODE:

int led = 9;           // the PWM pin the LED is attached to

int brightness = 0;    // how bright the LED is

int fadeAmount = 5;    // how many points to fade the LED by

// the setup routine runs once when you press reset:

void setup() {

  // declare pin 9 to be an output:

  pinMode(led, OUTPUT);

}

// the loop routine runs over and over again forever:

void loop() {

  // set the brightness of pin 9:

  analogWrite(led, brightness);

  // change the brightness for next time through the loop:

  brightness = brightness + fadeAmount;

  // reverse the direction of the fading at the ends of the fade:

  if (brightness <= 0 || brightness >= 255) {

    fadeAmount = -fadeAmount;

  }

  // wait for 30 milliseconds to see the dimming effect

  delay(30);

}

or you all can use this code also:

const int pwm=9;
void setup() {
  // put your setup code here, to run once:
pinMode(pwm,OUTPUT);
}

void loop() {
  
analogWrite(pwm,25);
delay(100);
analogWrite(pwm,75);
delay(100);
analogWrite(pwm,100);
delay(100);
analogWrite(pwm,125);
delay(100);
analogWrite(pwm,150);
delay(100);
analogWrite(pwm,175);
delay(100);
analogWrite(pwm,200);
delay(100);
analogWrite(pwm,255);
delay(100);

}