---

void setup() {
  // initialize digital pin LED_BUILTIN as an output.
  pinMode(12, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(11, OUTPUT);
  pinMode(9, OUTPUT);
}

void loop() {
  digitalWrite(12, HIGH);  // turn the LED on (HIGH is the voltage level)
  digitalWrite(10, HIGH);  // turn the LED on (HIGH is the voltage level)
  delay(1000);                      // wait for a second
  digitalWrite(12, LOW);   // turn the LED off by making the voltage LOW
  digitalWrite(10, LOW);   // turn the LED off by making the voltage LOW
  delay(1000);                      // wait for a second

  digitalWrite(12, HIGH);  // turn the LED on (HIGH is the voltage level)
  digitalWrite(10, LOW);  // turn the LED on (HIGH is the voltage level)
  digitalWrite(9, HIGH);  // turn the LED on (HIGH is the voltage level)
  delay(1000);                      // wait for a second
  digitalWrite(12, LOW);   // turn the LED off by making the voltage LOW
  digitalWrite(10, LOW);   // turn the LED off by making the voltage LOW
  digitalWrite(9, LOW);   // turn the LED off by making the voltage LOW
  delay(1000);                      // wait for a second
}