USB-Serial Converter Arduino Mega

/*
  Config begin
*/
#define SerialSpeed 9600
/*
  Config end
*/


#define

String inputString0 = "";
boolean string0Complete = false;

String inputString1 = "";
boolean string1Complete = false;

void setup() {
  Serial.begin(SerialSpeed);
  Serial1.begin(SerialSpeed);
  inputString0.reserve(200);
  inputString1.reserve(200);
}

void loop() {
  // print the string when a newline arrives:
  if (string0Complete) {
    Serial1.println(inputString0);
    // clear the string:
    inputString0 = "";
    string0Complete = false;
  }

    if (string1Complete) {
    Serial.println(inputString1);
    // clear the string:
    inputString1 = "";
    string1Complete = false;
  }
}

/*
  SerialEvent occurs whenever a new data comes in the
 hardware serial RX.  This routine is run between each
 time loop() runs, so using delay inside loop can delay
 response.  Multiple bytes of data may be available.
*/
void serialEvent() {
  while (Serial.available()) {
    // get the new byte:
    char inChar = (char)Serial.read();
    // add it to the inputString:
    inputString0 += inChar;
    // if the incoming character is a newline, set a flag
    // so the main loop can do something about it:
    if (inChar == '\n') {
      string0Complete = true;
    }
  }
}

void serialEvent1() {
  while (Serial1.available()) {
    // get the new byte:
    char inChar = (char)Serial1.read();
    // add it to the inputString:
    inputString1 += inChar;
    // if the incoming character is a newline, set a flag
    // so the main loop can do something about it:
    if (inChar == '\n') {
      string1Complete = true;
    }
  }
}