Arduino Baca_Taq_RFID_

#define LED_PIN 13
#include <SoftwareSerial.h>
SoftwareSerial RFID(2, 3);
String Teks;
String TeksCek;
char c;
void setup()
{
Serial.begin(9600);
RFID.begin(9600);
pinMode(LED_PIN, OUTPUT); //Sets LED pin as output
digitalWrite(LED_PIN, LOW); //Turn off LED
}


void loop()
{
while(RFID.available()>0){
delay(5);
digitalWrite(LED_PIN, HIGH); //Turn on LED
c=RFID.read();
Teks += c;
}
if(Teks.length()>10) Cek();
Teks="";

}

void Cek()
{
Teks=Teks.substring(1,11);
 if (TeksCek != Teks) {
    Serial.println("Tag RFID anda : "+Teks);
    digitalWrite(LED_PIN, LOW); //Turn off LED
    TeksCek = Teks;
  }
}