This design is password lock design of a relatively simple, taking into account the economic levels and the design of the reasons for the expansion of the function also not strong enough, but the primary function of a keyboard input, LED digital control, encryption, Change Password, password detection, Error alarm, unlock functions. Easy-to-understand, easy to use, high safety performance.
This design uses AT89S51 microcontroller chip for the main, the AT24C02 for use of brown-out memory chips. The chips, high stability, low cost, but also expansion of many functions. Such as infrared detection technology, fingerprint recognition technology, voice recognition technology, image recognition technology. These expansion of the technical development of the relatively rapidly abroad, some have been put into use. The design did not use these extensions.
The design of protel 99 software are used to draw circuit. A larger part in the show circuit because of too much could not integrated into a map, so I followed the one map.
Software design are used in the design of assembly language programming. The main part of the preparation of the main function of the realization of procedures, the design of the subroutine omitted.
Keywords: AT89S51; AT24C02; Electronic combination lock; Matrix keyboard