int red=3;
int yellow=4;
int green=5;
void setup() {
  // put your setup code here, to run once:
  Serial1.begin(115200);
  //Serial1.println("Hello, Raspberry Pi Pico!");
  pinMode(red,OUTPUT);
  pinMode(yellow,OUTPUT);
  pinMode(green,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(green,LOW);
  digitalWrite(red,HIGH);
  delay(100);
  digitalWrite(red,LOW);
  digitalWrite(yellow,HIGH);
  delay(100);
  digitalWrite(yellow,LOW);
  digitalWrite(green,HIGH);
  delay(100); // this speeds up the simulation
}