int rV;                  //value from potentiometer (0 - 1023)
float V;                 //actual value in volts
int lV;                  //value to led (0 - 255)

int led=3;              //setting LED out as digital pin 3
int pot=A0;             //setting potentiometer input as A0


void setup() {
  // put your setup code here, to run once:
  pinMode(led, OUTPUT); //estabishing digital pin 3 as PWM output
  pinMode(pot, INPUT);  //establishing A0 as analog input
  Serial.begin(9600);   //serial comm. established with baud rate 9600
}

void loop() {
  // put your main code here, to run repeatedly:
  rV=analogRead(pot);   //reading from A0 (value b/w 0 - 1023)
  V=(5.0/1023.0)*rV;    //converting the value received in A0 to volatge b/w 0 -5V
  lV=(255.0/1023.0)*rV; //converting the value in rV to PWM range of 0-255 to be used in D3
  analogWrite(led,lV);  //sending the value to D3 to switch ON the LED

  Serial.print("Potentiometer voltage = ");
  Serial.println(V);    //dispalys the actual voltage (0-5V)
  Serial.print("Pot value = ");
  Serial.println(rV);   //dispalys the A0 value (o-1023)
  Serial.print("LED value = ");
  Serial.println(lV);   //dispalys the D3 PWM value (0-255)
  delay(1000);          // provides a delay of 1s (1000ms) to the next cycle

}