With the development of society, people's daily schedules have become increasingly packed, requiring a clock that can accurately keep time. There is a growing demand for clocks that not only have a time error of less than a few milliseconds each day but also feature functions such as alarm clocks and perpetual calendars. Traditional electronic clocks with calendar functions have multiple components, are difficult to maintain, have large errors, and are not easily updated in terms of functionality. The DS12C887 clock chip automatically displays time information such as year, month, day, hour, minute, and second, while also offering time calibration, time reporting, alarm clock functions, among others. Additionally, the DS12C887 can be easily programmed via software to adjust or add functions. Therefore, the design of a high-precision clock based on the DS12C887 clock chip holds significant practical value and real-world significance. Keywords: DS12C887, clock chip, microcontroller STC89C52, high-precision clock.