کدتون رو به این صورت بنویسید درست میشه :
کد:
void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  String rey1 = "OFF";
  String rey2 = "OFF";
  String rey3 = "OFF";
  String rey4 = "OFF";
  String text = "Relay= R1=" + rey1 + ",R2=" + rey2 + ",R3=" + rey3 + ",R4=" + rey4;
  Serial.println(text);
}


void loop() {
  // put your main code here, to run repeatedly:
}