const int boton = 3;
const int led = 1;
int buttonState = 0;
int analogPin = A2; 
int val = 0;
 
void setup() 
{
  pinMode(led, OUTPUT);
  pinMode(boton, INPUT);
  
}
 
void loop()
{
  val = analogRead(analogPin);    // read the input pin
  val = map(val, 0, 1023, 0, 255);
  analogWrite(led, val);
}