apuntes_Arduino/leds/leds_pwm/leds_pwm.ino

void setup() {
    pinMode(10, OUTPUT);
    pinMode(11, OUTPUT);
    pinMode(9, OUTPUT);
}

void loop() {
    int i;
    int j;
    int k;
    for (i = 0; i <= 255; i++) {
        j = 255 - i;
        analogWrite(10, i);
        analogWrite(11, j);
        analogWrite(9, j);
        //delay(1);
    } 
    for (j = 255; j >= 0; j--) {
        i = 255 - j;
        analogWrite(10, i);
        analogWrite(11, j);
        analogWrite(9, j);
        //delay(1);
    }          
}