void setup() 
{
  pinMode(2, OUTPUT);
  Serial.begin(115200);
}

void loop() 
{
  Serial.print("HIGH ");
  digitalWrite(2, HIGH);
  delay(2000);

  Serial.print("LOW ");
  digitalWrite(2, LOW);
  delay(2000);
}
NOCOMNCVCCGNDINLED1PWRRelay Module
NOCOMNCVCCGNDINLED1PWRRelay Module
NOCOMNCVCCGNDINLED1PWRRelay Module