用c语言编写的数字时钟，有时分秒显示，并且时分秒都可调，误差较小。用AT89C51单片机连接数码管显示，程序用keil编写，实验仿真有protel99se实现，已验证成功-With the c language of the digital clock, sometimes minutes and seconds display, and when the minutes and seconds are adjustable, error smaller. AT89C51 microcontroller with digital tube display, the program using keil write, experimental simulation has protel99se implementation, has been successfully verified