Arduino (e.g., Uno, Mega, etc.) RFID Reader (e.g., RC522) RFID Tags or Cards LCD Display (optional, for showing status) Breadboard and Jumper Wires Reads the card UID when a new card is present.

I just received my RC522 RFID reader and made this simple Arduino access control system that uses the reader, a buzzer for the alarm and a relay shield for the security system. The relay can be used ...

unsigned char* BufferToMessage_Success(unsigned char* buffer, unsigned char* query, unsigned char slave_id); unsigned char* BufferToMessage_IllegalFunction(unsigned char* query, unsigned char slave_id ...