#define LED_SERIAL_PIN 13

void setup() {
  // put your setup code here, to run once:
  pinMode(LED_SERIAL_PIN, OUTPUT);
  Serial.begin(9600);
  Serial.println("Arduino Control of LED using a Serial Monitor");
}

void loop() {
  // put your main code here, to run repeatedly:
  char input = '\0';

  if (Serial.available()) {
    input = Serial.read();
  }

  switch (input) {
    case '1':
      digitalWrite(LED_SERIAL_PIN, HIGH);
      break;
    case '0':
      digitalWrite(LED_SERIAL_PIN, LOW);
      break;
    default:
      break;
  }
}
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