const int potPin = 27 ;
const int ledpin = 3 ;
void setup() {
  // put your setup code here, to run once:
  Serial1.begin(9600);
  pinMode(3, OUTPUT);
  
}

void loop() {
  int potValue =analogRead(27)
  int ledbrightness = map(potValue,0,1023,0,255)
  analogWrite(3,ledbrightness);
  // put your main code here, to run repeatedly:
  delay(100); // this speeds up the simulation
}