const int ledPin = 12;
const int freq = 5000;
const int ledChanel = 0;
const int resolution = 8;

void setup() {
  ledcSetup(ledChanel, freq, resolution);
  ledcAttachPin(ledPin, ledChanel);
}

void loop() {
  ledcWrite(ledChanel, 1);
  delay(15); // this speeds up the simulation
}