/* Program 5-5: Use analogWrite() function to dim an LED */

const int LED = 5;         /* connect an LED */

void setup() {
    pinMode(LED, OUTPUT);   /* set LED pin as output */
}

void loop() {
    int dutycycle;

    /* increase duty cycle from 0 to 255 */
    for (dutycycle = 0; dutycycle < 256; dutycycle++)
    {
         analogWrite(LED, dutycycle);
         delay(30);  /* let each duty cycle to last for 30ms */
    }
}