This paper describes the design of a multi-functiond digital clock system.It as displaying and setting time for clock and alarm .It is the system center that the real time clock DS12C887 and AT89C51. User can use the keyboard to modify the data that indicate the time data which include the daytime, alarm, date, etc. The data can be show by the LCD. It can be programmed the ringer which you like., this system has other special features such as temperature measurement and data protection at power faillure. The system takes liquid crystal display, matching with a key to provide amity of customer interface, the operation is simple, having the temperature examination function in the meantime, the clock data and the temperature data .consecution,credibility,stable work;Still have a physical volume in the meantime small,the power consume a low etc. characteristics, easy to take, the usage convenience.The system software design includes a single slice a plait distance with two parts of machine calculator.The calculator software plait distance mainly carries out a parameter constitution,string to go a people's data to receive,the instruction send out and data of manifestation with saving..Singlelicethemachinesoftwareplaitdistance,LCDmanifestation,temperature examination each mold of etc. piece.
Key words: Single—Chip computer, the real time clock, keyboard, LCD
