#define ONBOARD_LED  2
#define MOTION_SENSOR 13

int pinStateCurrent   = LOW; 
int pinStatePrevious  = LOW;  

void setup() {
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
  pinMode(ONBOARD_LED,OUTPUT);
  pinMode(MOTION_SENSOR, INPUT);
}

void loop() {
  pinStatePrevious = pinStateCurrent;
  pinStateCurrent = digitalRead(MOTION_SENSOR);   

  if (pinStatePrevious == LOW && pinStateCurrent == HIGH) {  
    Serial.println("Motion detected!");
    digitalWrite(ONBOARD_LED, HIGH);
  }
  else if (pinStatePrevious == HIGH && pinStateCurrent == LOW) {   
    Serial.println("Motion stopped!");
    digitalWrite(ONBOARD_LED, LOW);
  }
}