Arduino-XRF beacon

#include <SoftwareSerial.h>

#define SEND_DELAY 5000
#define LED_PIN 13

SoftwareSerial mySerial(2, 3); // RX, TX

void setup()
{
  pinMode(LED_PIN, OUTPUT);

  digitalWrite(LED_PIN, HIGH);
  delay(1000);
  digitalWrite(LED_PIN, LOW);

  // Open serial communications and wait for port to open:
  Serial.begin(9600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only
  }

  Serial.println("SETUP Arduino");

  // set the data rate for the SoftwareSerial port
  mySerial.begin(9600);
}

char beacon[]="abcdef";
char answer[]="fedcba";

char input[]="000000";

unsigned long timeLastSend = 0;
unsigned long led_on_time = 0;
unsigned i=0;

void loop() // run over and over
{
    unsigned char c;

    if (millis() > timeLastSend){
        mySerial.write(beacon);

        timeLastSend = millis()+SEND_DELAY;

        led_on_time = millis()+200;
        digitalWrite(LED_PIN, HIGH);

        Serial.println("Sending beacon...");
    }

    if (millis() > led_on_time){
        digitalWrite(LED_PIN, LOW);
    }


    if (mySerial.available()){
        c = mySerial.read();

        Serial.print("r:");
        Serial.print(c);

        if ( c == answer[0]){
            i=1;
            input[0]=c;
        }else if(i > 0){
                input[i] = c;
                i++;
        }
    }
    if ( i >= strlen(beacon)){
            if (strcmp(input, answer) == 0){
            digitalWrite(LED_PIN, HIGH);
            led_on_time = millis()+700;
            Serial.println("GOT BEACON");
        }else{
            Serial.println("beacon failed...");
            strcpy("000000",input);
        }
        i=0;
    }
}