Design of Password Lock Based on Fingerprint Recognition

Abstract

In recent years, with the rapid development of science and technology, fingerprint identification has been applied to many fields and achieved good results. Fingerprint identification has high security. The progress of all kinds of science and technology has gradually reduced its production cost. This also promotes the rapid development of fingerprint identification.Therefore, in this design, a fingerprint identification electronic password lock system is designed with a single chip microcomputer as the core. The single chip microcomputer is used for fingerprint identification and password identification, and the LCD screen is used to display the corresponding interface and data. The sampling relay module simulates unlocking, LED lights and buzzers. Perform button prompts and alarm processing. The overall volume of the system designed in this design is small and has a high cost performance. This design is based on 51 single chip microcomputer as the basis to design a fingerprint identification electronic code lock, combined with the design requirements, the STC89C54RD+ single chip microcomputer is selected, and the fingerprint module is ZFM-40, which has rich functions and can access fingerprints. It communicates with the fingerprint module ZFM-40 through the UART function of STC89C54RD+, and the specific exchanged content is realized in the form of code. The liquid crystal equipment selected is HS12864-15C, which has a high degree of integration and is suitable for ordinary family use. Through the 3-wire serial data interface and the microcontroller for data transmission, the corresponding interface and data are displayed on the HS12864-15C, such as: main menu, administrator interface, unlocking and error information, etc., which is convenient for users to view and use. In the design, the relay is used to simulate the lock, and the high and low level output of one pin of the single-chip microcomputer controls the closing of the relay public end and the normally open and normally closed ports, so as to control the power on and off of the strong electric device to achieve the purpose of unlocking. The test results meet expectations, the functions envisaged in the early stage are basically realized, and the design has the characteristics of low cost.