/* Program 4-7: Echo the received characters of the Serial1 port of Mega
 * 
 * Connect a 5V Serial to USB converter from the Mega to
 * the PC. Pin PD3 of the Mega is TxD1 and should be connected
 * to the Rx of the USB converter. Pin PD2 of the Mega is RxD1 
 * and should be connected to the Tx of the USB converter. 
 * 	
 * Use a terminal emulator such as Tera Term or Putty to send 
 * characters and see the output.
 */

void setup() { 
    Serial1.begin(9600);    /* initialize serial1 and set the Baud rate to 9600 */
} 

void loop() {
    while (!Serial1.available()) { }    /* wait until a char is available */
    char c = Serial1.read();            /* read the character */
    Serial1.write(c);                   /* echo the character received */
}