[Arduino] Led Fade In / Fade Out

 Hi,

so, you have nothing to do on this afternoon? Good, you can waste your time doing this: a simple fade in/ fade out effects with your christmas red led...

What you need:

• Arduino Uno
• Led
• Some cables
• Resistor 220 ohm

The fade in/fade out effect is realized through the Pulsar-Width Modulation (PWM) that according wikipedia is : 

 "a method of reducing the average power delivered by an electrical signal, by effectively chopping it up into discrete parts"

 The connection is this:

• GND (Arduino) -> Resistor -> LED (short leg)
• PIN 9 (Arduino) -> LED (the other leg) 

You can follow this schema

And this is the code you cane use

int LED = 9; 

int msDelay = 5; //ms

void setup() { 

   pinMode(LED, OUTPUT); 

} 

void loop() {

   // PWM from 0 to 255 (fade in)

   for(int pwmValue = 0; pwmValue <= 255; pwmValue++){ 

      analogWrite(LED, pwmValue);

      delay(msDelay);

   }

   

   // PWM from 255 to 0 (fade out) 

   for(int pwmValue = 255; pwmValue >= 0; pwmValue--){

      analogWrite(LED, pwmValue);  

      delay(msDelay); 

   }

} 

Now your afternoon has more sense....