int value1;
int value2;

void setup() 
{
  Serial.begin(9600);

  pinMode(3,OUTPUT);
}

void loop() 
{
  value1 = analogRead(A5);
  value2 = map(value1,0,1023,0,255);

  analogWrite(3,value2);
  delay(100);

  Serial.print(value1); Serial.print(":"); Serial.println(value2);
  
}