#define LED 13
void setup() {
// put your setup code here, to run once:
Serial.begin(115200);
Serial.println("Hello, STM321");
pinMode(LED, OUTPUT);
}

void loop() {
// put your main code here, to run repeatedly:
digitalWrite(LED, HIGH);
delay(1000); // 1 seconds
digitalWrite(LED, LOW);
delay(1000);
}