#define SWITCHpIN 19

void setup() {
  
  Serial.begin(115200);
  pinMode(SWITCH_PIN, INPUT_PULLUP);
  Serial.println("Hello, ESP32!");
}

void loop() {
if(digitalRea(SWITCH_PIN)==LOW){
  Serial.println("SWITCH ON");
}else{
  Serial.println("SWITCH OFF");
}

}