String inputString = "";         // a String to hold incoming data
bool stringComplete = false;  // whether the string is complete
String inputString1 = "";         // a String to hold incoming data
bool stringComplete1 = false;  // whether the string is complete
String inputString3 = "";         // a String to hold incoming data
bool stringComplete3 = false;  // whether the string is complete
int index=0;
int baud=115200;
#define commands 5
char *command[]= {
  "help",
  "Hi",
  "To1:",
  "To3:",
  "4"
};

void setup() {
  // Open serial communications and wait for port to open:
  Serial.begin(115200);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB port only
  }

  inputString1.reserve(200);
  inputString3.reserve(200);
  // Start each software serial port
  Serial1.begin(115200);
  while (!Serial1) {
    ; // wait for serial port to connect. Needed for native USB port only
  }
  Serial3.begin(115200);
  while (!Serial3) {
    ; // wait for serial port to connect. Needed for native USB port only
  }
  Serial.println("Ready!");
}

void loop() {
  if (stringComplete) {
    Serial.print(inputString);
    if (inputString.substring(0,5)=="help\n"){
      char *string="";
      int i;
      Serial.println("Help:");
      Serial.print(commands,DEC);
      Serial.println(" commands: ");
      for (i=0;i<commands;i++){
        sprintf(string,"%d : %s size: %d\n",i,command[i], strlen(command[i]));

        Serial.print(string);
      }
    }
    if (inputString.substring(0,strlen(command[1]))==command[1]){
      Serial.println("Hello");
    }
    else if (inputString.substring(0,strlen(command[2]))==command[2]){
      Serial.println("Send to 1:");
      Serial.println(inputString.substring(4));
      Serial1.println(inputString.substring(4));
    }
    else if (inputString.substring(0,strlen(command[3]))==command[3]){
      Serial.println("Send to 3:");
      Serial.println(inputString.substring(4));
      Serial3.println(inputString.substring(4));
    }
    else{
      //Serial.println("OK");
    }
      // clear the string:
    inputString = "";
    stringComplete = false;
  }
  if (stringComplete1) {

    Serial.print("1:");
    Serial.print(inputString1);
    Serial3.print(inputString1);

      // clear the string:
    inputString1 = "";
    stringComplete1 = false;
  }
  if (stringComplete3) {

    Serial.print("3:");
    Serial.print(inputString3);
    Serial1.print(inputString3);

      // clear the string:
    inputString3 = "";
    stringComplete3 = false;
  }
}

void serialEvent() {

  while (Serial.available()) {
    // get the new byte:
    char inChar = (char)Serial.read();
    // add it to the inputString:
    inputString += inChar;
    // if the incoming character is a newline, set a flag so the main loop can
    // do something about it:
    if (inChar == '\n') {
      stringComplete = 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') {
      stringComplete1 = true;
    }
  }
}

void serialEvent3() {

  while (Serial3.available()) {
    // get the new byte:
    char inChar = (char)Serial3.read();
    // add it to the inputString:
    inputString3 += inChar;
    // if the incoming character is a newline, set a flag so the main loop can
    // do something about it:
    if (inChar == '\n') {
      stringComplete3 = true;
    }
  }
}