用STC最小系统的实时时钟设计实现数字钟。 可以切换年月日时分秒显示，支持时钟设计功能 用Keil C51编程实现上述功能 用Keil与Proteus联调. -With minimum on STC system real time clock design for digital clock. Can switch when (date) (month) (year), according to minutes support clock design functions Use