Control an LED With PWM Output

by dev.alessiobigini in Circuits > Arduino

10748 Views, 24 Favorites, 0 Comments

Control an LED With PWM Output

10966922_718353928262563_2052976409_n.jpg
duty_cycle.gif

As you may have noticed in the Arduino board (Uno, Mega-etc.) Are present some PIN that have next a symbol like a wave.

This symbol indicates that the output can also be used in "PWM" or "Pulse-width modulation".
Using this function, it is possible to vary, for example, the frequency of switching on and off of an LED.

The Circuit

Cattura di schermata (17).png

First we need to:

- Arduino Uno

- A resistor 220Ohm

- A LED

- Breadboard

- Wires for links

Mounted the circuit as described in the picture

The Sketch

10968112_718353938262562_350337577_n-e1423230337722.jpg

// Created by //

// Alessio Bigini 2015 //

// http://alessiobigini.it //

int lum = 0;

void setup()

{

pinMode(9, OUTPUT);

}

void loop()

{

for (lum = 0; lum < 255; lum++ )

{

analogWrite(9, lum);

delay(10);

}

for (lum = 255; lum > 0; lum-- )

{

analogWrite(9, lum);

delay(10);

}

}

Now load the sketch into your board

In this code I used two simple For loops that allow me to increase the variable "Lum" from 0 to 255 and then decrease it.

Downloads

The Video

Arduino: uscita PWM e LED