const int8_t ledPin = 23;
int8_t ledState = LOW;

unsigned long previousMillis = 0;

const unsigned long interval = 1000;

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

void loop() {
  // put your main code here, to run repeatedly:
  // delay(10); // this speeds up the simulation

  unsigned long currentMillis = millis();

  if(currentMillis - previousMillis >= interval){
    previousMillis = currentMillis;

    // if(ledState == LOW){
    //   ledState = HIGH;
    // } else {
    //   ledState = LOW;
    // }
    ledState = !ledState;
    digitalWrite(ledPin, ledState);
  }

  // digitalWrite(ledPin, ledState);
}