strange serial sending problem

Projects Programming
2

You should find if it is the usb or the processor that is malfunctioning. Try this:

void setup() {
   Serial.begin(9600);
   pinMode(13,OUTPUT);
}

void loop() {
  Serial.println("hallo");
  digitalWrite(13,HIGH);
  delay(1000);
  Serial.println("bye");
  digitalWrite(13,LOW);
  delay(1000); 
}

Disconnect, then reconnect the Arduino. If the onboard pin 13 LED is on for a second and off for a second over and over, the code is still running. If not, the code has failed.