void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
  pinMode(4,OUTPUT);
  pinMode(12, INPUT);
}

void loop() {
   int value=analogRead(12);
   Serial.println(value);
   int bright=map(value,0,4095,0,255);
   analogWrite(4,bright);
  delay(500); // this speeds up the simulation
}