//Reading an analog sensor (Potentiometer; Light Dependant Resister; IR Ranger; Thermister etc) 
//And writing an 'analog' output using Pulse Width Modulation

int analogPin = 3;     // potentiometer wiper (middle terminal) connected to analog pin 3
                       // outside leads to ground and +5V
                       
int val = 0;           // variable to store the value read

void setup()
{
  Serial.begin(115200);          // setup serial
  pinMode(11,OUTPUT);            // Set pin 11 to be an output because we're going to use it for PWM
}

void loop()
{
  val = analogRead(analogPin);     // read the input pin
  Serial.println(val);             // debug value
  
  analogWrite(11,val/4);           // divide the potentiometer reading by 4 because its values are between
                                   // 0 & 1023 - but the PWM values can only be upto 255!
  
}