[code]

#include <SD.h> //load the SD library
#include <SPI.h> //load the SPI communication library
#include <RTClib.h>
#include "Wire.h"    // imports the wire library for talking over I2C
#include "Adafruit_PN532.h"  // import the RFID sensor Library

#define LOG_INTERVAL  1000 // mills between entries (reduce to take more/faster data)
#define SYNC_INTERVAL 1000 // mills between calls to flush() - to write data to the card
uint32_t syncTime = 0;     // time of last sync()

#define ECHO_TO_SERIAL   1 // echo data to serial port
#define WAIT_TO_START    0 // Wait for serial input in setup()

// the digital pins that connect to the LEDs
#define redLEDpin 4
#define greenLEDpin 5

#define PN532_IRQ   (2)  //defines pins connected to the IRQ and reset lines.
#define PN532_RESET (3)

Adafruit_PN532 nfc(PN532_IRQ, PN532_RESET);;  // create sensor object
RTC_PCF8523 rtc; // define the Real Time Clock object

const int chipSelect = 10; //For data logging shield, digital pin 10 used for SD cs line
File logfile; //Variable for working with our file object

void error(char *str)
{
  Serial.print("error: ");
  Serial.println(str);

  // red LED indicates error
  digitalWrite(redLEDpin, HIGH);

  while(1);
}


void setup(void){

  Serial.begin(115200);
  Serial.println("Hello!");

  //RFID Setup

  nfc.begin();

  uint32_t versiondata = nfc.getFirmwareVersion();
  if (! versiondata) {
    Serial.print("Didn't find PN53x board");
    while (1); // halt
  }
  // Got ok data, print it out!
  Serial.print("Found chip PN5"); Serial.println((versiondata>>24) & 0xFF, HEX);
  Serial.print("Firmware ver. "); Serial.print((versiondata>>16) & 0xFF, DEC);
  Serial.print('.'); Serial.println((versiondata>>8) & 0xFF, DEC);

  // configure board to read RFID tags
  nfc.SAMConfig();

  Serial.println("Waiting for an ISO14443A Card ...");


  // initialize the SD card
  Serial.print("Initializing SD card...");
  // make sure that the default chip select pin is set to
  // output, even if you don't use it:
  pinMode(10, OUTPUT);

  // see if the card is present and can be initialized:
  if (!SD.begin(chipSelect)) {
    error("Card failed, or not present");
  }
  Serial.println("card initialized.");

  // create a new file
  char filename[] = "LOGGER00.CSV";
  for (uint8_t i = 0; i < 100; i++) {
    filename[6] = i/10 + '0';
    filename[7] = i%10 + '0';
    if (! SD.exists(filename)) {
      // only open a new file if it doesn't exist
      logfile = SD.open(filename, FILE_WRITE);
      break;  // leave the loop!
    }
  }

  if (! logfile) {
    error("couldnt create file");
  }

  Serial.print("Logging to: ");
  Serial.println(filename);
  Serial.println("");

  // connect to RTC
  Wire.begin();
  if (!rtc.begin()) {
    logfile.println("RTC failed");
#if ECHO_TO_SERIAL
    Serial.println("RTC failed");
#endif  //ECHO_TO_SERIAL
  }
}
void loop(void)
{
  int motor = 7;
  uint8_t success;
  uint8_t uid[] = { 0, 0, 0, 0, 0, 0, 0 };  // Buffer to store the returned UID
  uint8_t uidLength;                        // Length of the UID (4 or 7 bytes depending on ISO14443A card type)
  int i = 0;

//Wait for an ISO14443A type cards (Mifare, etc.)
success = nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A, uid, &uidLength);

  if (success) {
    // Display some basic information about the card
    Serial.println("Found an ISO14443A card");
    Serial.print("  UID Length: ");Serial.print(uidLength, DEC);Serial.println(" bytes");
    Serial.print("  UID Value: ");
    nfc.PrintHex(uid, uidLength);
    Serial.println("");

    if (uidLength == 4)
    {
      // We probably have a Mifare Classic card ...
      //Serial.println("Seems to be a Mifare Classic card (4 byte UID)");

      // Now we need to try to authenticate it for read/write access
     // Serial.println("Trying to authenticate block 4 with default KEYA value");
      uint8_t keya[6] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };

      success = nfc.mifareclassic_AuthenticateBlock(uid, uidLength, 4, 0, keya);

      if (success)
      {
        //Serial.println("Sector 1 (Blocks 4..7) has been authenticated");
        uint8_t data[16];

                success = nfc.mifareclassic_ReadDataBlock(4, data);

        if (success)
        {
          // Data seems to have been read ... spit it out
          //Serial.println("Reading Block 4:");
          //nfc.PrintHexChar(data, 16);
          //Serial.println("");

          // Wait a bit before reading the card again
          delay(1000);
        }
        else
        {
          Serial.println("Ooops ... unable to read the requested block.  Try another key?");
        }
      }
      else
      {
        Serial.println("Ooops ... authentication failed: Try another key?");
      }
    }

  {

 logfile.println("date, time, IDnumber");
#if ECHO_TO_SERIAL
  Serial.println("date, time, IDnumber");
#endif //ECHO_TO_SERIAL

  DateTime now;

  // delay for the amount of time we want between readings
  delay((LOG_INTERVAL -1) - (millis() % LOG_INTERVAL));

  digitalWrite(greenLEDpin, HIGH);

  // log milliseconds since starting
  uint32_t m = millis();
  //logfile.print(m);           // milliseconds since start
  //logfile.print(", ");
//#if ECHO_TO_SERIAL
  //Serial.print(m);         // milliseconds since start
  //Serial.print(", ");
//#endif

  // fetch the time
  now = rtc.now();
  // log time
  //logfile.print(now.unixtime()); // seconds since 1/1/1970
  //logfile.print(", ");
  //logfile.print('"');
  logfile.print(now.year(), DEC);
  logfile.print("/");
  logfile.print(now.month(), DEC);
  logfile.print("/");
  logfile.print(now.day(), DEC);
  logfile.print(",");
#if ECHO_TO_SERIAL
  Serial.print(now.year(), DEC);
  Serial.print("/");
  Serial.print(now.month(), DEC);
  Serial.print("/");
  Serial.print(now.day(), DEC);
  Serial.print(", ");
#endif //ECHO_TO_SERIAL

  logfile.print(now.hour(), DEC);
  logfile.print(":");
  logfile.print(now.minute(), DEC);
  logfile.print(":");
  logfile.print(now.second(), DEC);
  logfile.print(",");
#if ECHO_TO_SERIAL
  //Serial.print(now.unixtime()); // seconds since 1/1/1970
  //Serial.print(", ");
  //Serial.print('"');
  Serial.print(now.hour(), DEC);
  Serial.print(":");
  Serial.print(now.minute(), DEC);
  Serial.print(":");
  Serial.print(now.second(), DEC);
#endif //ECHO_TO_SERIAL

for (uint8_t i=0; i < uidLength; i++)
{
    if(uid[i]<0x10);
}

logfile.print(uid[i], HEX);  // Write id number to the SD card
logfile.print(",");
//logfile.close(); //Close the file
#if ECHO_TO_SERIAL
  Serial.print(", ");
  Serial.print(F(" 0x")); Serial.print(uid[i], HEX);
  //nfc.PrintHex(uid, uidLength);
  Serial.println("");
#endif //ECHO_TO_SERIAL

 logfile.println();
#if ECHO_TO_SERIAL
  Serial.println();
#endif // ECHO_TO_SERIAL



if ((millis() - syncTime) < SYNC_INTERVAL) return;
  syncTime = millis();

  // blink LED to show we are syncing data to the card & updating FAT!
  digitalWrite(redLEDpin, HIGH);
  logfile.flush();
  digitalWrite(redLEDpin, LOW);

  // code for vibrating motor disc
  pinMode(success, INPUT);
  pinMode(motor, OUTPUT);

  if(digitalRead(success) == HIGH) { //If RFID card is detected, turn motor on
    digitalWrite(motor, HIGH);
    delay(500);                       //Hold vibration
    digitalWrite(motor, LOW);        //Turn motor off
    }
   }
  }
}
[/code]