Arduino.ru

 int incomingByte;
  
void setup() {
  pinMode(2, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(7, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(11, OUTPUT);

}

void loop() {
 if (Serial.available() > 0)
    {
      incomingByte = Serial.read(); 
    if(incomingByte == 'z')
      digitalWrite(2, HIGH);  
    if(incomingByte == 'x')
      digitalWrite(4, HIGH); 
    if(incomingByte == 'c')
      digitalWrite(7, HIGH); 
    if(incomingByte == 'v')
      digitalWrite(9, HIGH); 
    if(incomingByte == 'b')
      digitalWrite(11, HIGH);
} 
}