// the setup function runs once when you press reset or power the board
void setup() {
  // open the serial port at 115200 bps.
  // IMPORTANT: In Arduino boards its 9600 but in Pico its 115200.
  Serial1.begin(115200);
  // initialize digital pin LED_BUILTIN as an output.
  pinMode(10, OUTPUT);
  pinMode(9, OUTPUT);
}

// the loop function runs over and over again forever
void loop() {
  // Those on top are led 10
  // Those on below are led 9
  digitalWrite(10, HIGH);  // turn the LED on (HIGH is the voltage level)
  digitalWrite(9, LOW);
  Serial1.println("Led 10 high, led 9 low.");
  delay(1000);                      // wait for a second
  digitalWrite(10, LOW);   // turn the LED off by making the voltage LOW
  digitalWrite(9, HIGH);
  Serial1.println("Led 10 low, led 9 high.");
  delay(1000);                      // wait for a second
}