摘要：在日常生活和工作中，我們常常用到計時控制，如擴印過程中的曝光計時等。早期常用的一些時間控制單元都使用模擬電路設計制作的，其計時準確性和重復精度都不是很理想，現在基本上都是基于數字技術的新一代產品，隨著單片機性能價格比的不斷提高，新一代產品的應用也越來越廣泛，大可構成復雜的工業過程控制系統，完成復雜的控制功能。小則可以用于家電控制，甚至可以用于兒童電子玩具。它功能強大，體積小，質量輕，靈活好用，配以適當的接口芯片，可以構造各種各樣、功能各異的微電子產品。數字電子鐘的設計方法有多種，例如，可用中小規模集成電路組成電子鐘，也可以利用專用的電子鐘芯片配以顯示電路及其所需要的外圍電路組成電子鐘：還可以利用單片機來實現電子鐘等等。這些方法都各有特點，其中，利用單片機實現的電子鐘具有編程靈活，便于電子鐘功能的擴充，精確度高等。

關鍵詞：單片機、數字時鐘、程序設計

Abstract：In daily life and work, we often used for timing control, such as Print process, such as exposure time to time. Early common control unit for some time to use the analog circuit design, and its timing accuracy and repeatability are not very satisfactory, and now are basically a new generation of digital technology-based products, with the constant cost-effective single-chip increase the application of a new generation of products has become increasingly widespread, they could constitute a complex industrial process control system, the completion of complex control functions. Small appliances can be used to control, or even electronic toys for children. It is powerful, small size, light weight, flexible and easy to use, with appropriate interface chip, can construct a wide range, functions of different micro-electronics products. The design of digital electronic clock a number of means, for example, can be used integrated circuits composed of small and medium-sized electronic bell, can also use a dedicated chip with an electronic clock display circuit and its peripheral circuits needed for the composition of electronic bell: can also use a single machine to achieve the electronic bell and so on. These methods have different characteristics, which, using an electronic bell Singlechip with programming flexibility, ease of electronic bell function of the expansion of higher accuracy.

Key words: single-chip, digital clock, program design