The design and implementation of a RFID reader based on MFRC531

The radio frequency identification is a technology which is using a radio frequency communication to achieve non-contact and automatic identification. It also takes advantage of the radio frequency signals´ spatial coupling (alternating magnetic or electromagnetic fields) to achieve non-contact transmission of information. Meanwhile, it can achieve the purpose of identifying the object by passing the information. The reader´s system of the RFID is based on Phillip´s MFRC531. Its read-distance is about 10cm. The design introduces this system in detail from the hardware´s design and software´s programming. The design of the hardware is made up of the MCU (AT89S51) circuit, the RF circuit (MFRC531), the antenna circuit, the memory circuit (AT24C16), the serial communication and the power circuit. The programming of the software contains the RF´s initialization, the reading and writing to the card, the verification to the key, the communication between the microcontroller and the PC through UART.