/*   Serial communication with the Arduino 
 *   using any serial communication application
 * Setup: -Wire an LED from digital pin 7 thru 330ohm resistor to gnd
 *        -Piezo disk between digital pin 8 and Gnd
 */
   
 byte inByte;
 int LEDpin = 7;

 void setup(){
    Serial.begin(9600);             // Begin serial communication
    pinMode(LEDpin, OUTPUT);        // set digital pin 7 as input
 }

void loop(){
    if (Serial.available() > 0){           // only if serial data's there
       inByte = Serial.read();             // read it, store in inByte                       
            if (inByte == 49){             // if serial value = "1" key
               digitalWrite(LEDpin, HIGH); // light LED, otherwise
               tone(8, 440, 80);           // syntax: tone(pin, freq, duration)
             } else if(inByte == 50){      // Key is "2"  
               digitalWrite(LEDpin, HIGH); // light LED, otherwise                 
               tone(8, 640, 80);    
             } else if (inByte == 0) {
              digitalWrite(LEDpin, LOW);   // Otherwise, LED off
             }
       }
 }