> For the complete documentation index, see [llms.txt](https://emotiv.gitbook.io/extender-manual/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://emotiv.gitbook.io/extender-manual/hardware_triggering/example-2-serial-triggering.md).

# Example 2: Serial Triggering

This example uses the same setup for the arduino.  The arduino listens to a serial port on your computer  with a baud rate of 9600bps. Each time a value of 1 is sent to the serial port a trigger pulse is generated.

```
/*
  Trigger and blink on serial command.
*/


// the setup function runs once when you press reset or power the board
void setup() {
  pinMode(9, OUTPUT);
  Serial.begin(9600);
  Serial.write("Extender Trigger Example \n")
}

// the loop function runs forever
void loop()
{
  if (Serial.available() > 0)
  {
    int value = Serial.read();
    Serial.write(value);
    if (value == 1) {
        digitalWrite(9, HIGH);
        delay(100);                          	
        digitalWrite(9, LOW);                                  
    }
    
    else {
      Serial.write("Undefined Input\n"); 
    }
  }
}

```