TKJ Electronics

This project is about my RFID Modded Safe.

I’ve modded an old electronic toy-safe, which is unlocked by typing the 4-char password.

RFID Modded Safe

I’ve unsoldered the locking-mechanism from the circuitboard, and connected it to the Arduino instead.

Locking-Mechanism Hack

Then I connected a ID-20 RFID Reader to the Arduino and programmed it to read the tag, and see if it was allowed to enter the safe.

ID-20 RFID Reader

If it was allowed, the Arduino will keep the safe unlocked in 3 seconds!

I’ve also made this video to show how it works:
httphd://www.youtube.com/watch?v=oxuD–7wWE8

You can grab the code here, and try it out:

#include <NewSoftSerial.h>

NewSoftSerial ID12(5,6);
//                RX,TX

// RFID reader ID-12 for Arduino
// Based on code by BARRAGAN
// and code from HC Gilje - http://hcgilje.wordpress.com/resources/rfid_id12_tagreader/
// Modified for Arudino by djmatic
// Modified for ID-12 and checksum by Martijn The - http://www.martijnthe.nl/
//
// Use the drawings from HC Gilje to wire up the ID-12.
// Remark: disconnect the rx serial wire to the ID-12 when uploading the sketch


void setup() {
  Serial.begin(9600);                                 // connect to the serial port
  ID12.begin(9600);
  pinMode(12, OUTPUT);
}

void loop () {
  byte i = 0;
  byte val = 0;
  byte code[6];
  byte checksum = 0;
  byte bytesread = 0;
  byte tempbyte = 0;

  if(ID12.available() > 0) {
    if((val = ID12.read()) == 2) {                  // check for header
      bytesread = 0;
      while (bytesread < 12) {                        // read 10 digit code + 2 digit checksum
        if( ID12.available() > 0) {
          val = ID12.read();
          if((val == 0x0D)||(val == 0x0A)||(val == 0x03)||(val == 0x02)) { // if header or stop bytes before the 10 digit reading
            break;                                    // stop reading
          }

          // Do Ascii/Hex conversion:
          if ((val >= '0') && (val <= '9')) {
            val = val - '0';
          } else if ((val >= 'A') && (val <= 'F')) {
            val = 10 + val - 'A';
          }

          // Every two hex-digits, add byte to code:
          if (bytesread & 1 == 1) {
            // make some space for this hex-digit by
            // shifting the previous hex-digit with 4 bits to the left:
            code[bytesread >> 1] = (val | (tempbyte << 4));

            if (bytesread >> 1 != 5) {                // If we're at the checksum byte,
              checksum ^= code[bytesread >> 1];       // Calculate the checksum... (XOR)
            };
          } else {
            tempbyte = val;                           // Store the first hex digit first...
          };

          bytesread++;                                // ready to read next digit
        }
      }

      // Output to Serial:

      if (bytesread == 12) {                          // if 12 digit read is complete
        Serial.print("5-byte code: ");
        for (i=0; i<5; i++) {
          if (code[i] < 16) Serial.print("0");
          Serial.print(code[i], HEX);
          Serial.print(" ");
        }
        Serial.println();

        Serial.print("Checksum: ");
        Serial.print(code[5], HEX);
        Serial.println(code[5] == checksum ? " -- passed." : " -- error.");
        Serial.println();

        if (code[0] == 0x01 && code[1] == 0x07 && code[2] == 0x7A && code[3] == 0x21 && code[4] == 0xD9 && code[5] == checksum) {
          Serial.println("Case Unlocked by User1");
          digitalWrite(12, HIGH);
          delay(3000);
          Serial.println("Case Locked");
          digitalWrite(12, LOW);
        }
        if (code[0] == 0x01 && code[1] == 0x07 && code[2] == 0x7A && code[3] == 0x1A && code[4] == 0xBA && code[5] == checksum) {
          Serial.println("Case Unlocked by User2");
          digitalWrite(12, HIGH);
          delay(3000);
          Serial.println("Case Locked");
          digitalWrite(12, LOW);
        }
      }

      bytesread = 0;
    }
  }
}