// Uses two LEDs for demo purposes
// ledPin = LED that will flash the specified number of times
// rxPin = LED that will flash once for each serial byte received

int ledPin = 9;
int rxPin = 8;
int b;
int n;

void setup(){
  pinMode(ledPin, OUTPUT);
  pinMode(rxPin, OUTPUT);
  Serial.begin(9600);
}

void loop(){
  
  // Read in the next available byte and blink the rx LED once
  if(Serial.available() > 0){
    b = Serial.read();
    Serial.println(b);
    blink(rxPin, 1, 25);
  }

  // Subtract 48 to convert ASCII char to right integer ("1" = 49)
  n = int(b) - 48;
  
  // If number received, flash LED correct number of times
  if(n > 0) {
    Serial.print("F"); Serial.println(n);
    blink(ledPin,n,75);
    delay(500);
  } 
  n = 0;
  b = 0;
 
}

void blink(int pin, int count, int ms) {
  int x;
  for(x = 0; x < count; x++) {
      digitalWrite(pin, HIGH);
      delay(ms);
      digitalWrite(pin, LOW);
      delay(ms);
  }
}