Abstract
With the developing of the technology, the people are becoming more and more attach importance to the safety of insurance devices in the daily life, security has become one of the focuses which are paid to much attention. In order to meet the requirements of the people to increase the security of locks, the key to the lock replaced by the password came into being. This paper discusses the designing process of the hardware and software of the electronic code lock in detail，which is controlled by the AT89C51 single-chip microcomputer. This electronic products controls the circuit or chips by inputting the password, so as to close the mechanical switch and complete the task of lock or unlock. It consists of determinant keyboard, the circuit of display, input and output control circuits, alarming circuit. This electronic code lock is designed to use AT89C51 microprocessor as a control components .And with its advantage of safety, low cost, low power consumption, easy-to-use, etc., it overcomes the shortcoming of the general lock that the users have to carry the key which is easy to loss. So it is applied in hotels, office buildings, warehouses, safe and large supermarkets universally. Based on the above ideas, in general the functions of the single-chip code lock are as follows:
1. The user can set different passwords freely.
2. Alarming function..
3. You can set an almighty password.
4. The power-down memory function.
