//Send Receive Data Test (Arduino Mega)

//vars
unsigned long lgUpdateTime;
char val[];

void setup()
{
         Serial.begin(9600);
         Serial1.begin(9600);
         lgUpdateTime = millis();
}

void loop()
{
         //Excute loop every 1 second
	     if(millis() - lgUpdateTime > 1000) 
         {
               lgUpdateTime = millis();
               
               if (Serial1.available() > 0)
               {
                    //Read Data From App
                    val = Serial1.read();
               
                    //Send same Data back to App
                    Serial.print(val)
                    Serial.println() //App 'end of data' ASCII Char 10 
               }
         }
}