"AT89C51单片机智能密码锁设计：经济实用、安全可靠、操作方便"

The design of an intelligent electronic combination lock controlled by a single-chip microcomputer is presented in this document. The system, featuring automatic alarm functions, is based on the AT89C51 microcontroller and incorporates peripheral components such as a keyboard input, digital display, alarm system, and lock mechanism. It allows for password input, deletion, comparison, unlocking with the correct password, and triggering an alarm if an incorrect password is entered multiple times. This system is characterized by its simplicity in design, ease of development, low cost, reliability, and user-friendly operation. It is suitable for use in residential and office safes, as well as filing cabinets in need of theft prevention, demonstrating practicality and effectiveness. Key words: electronic combination lock; matrix keyboard; alarm; digital display.