描述了24小时计时的数字钟，同时具有分秒计时的功能-Described a 24-hour digital time clock, at the same time every minute timer function

关于数字钟的实现，用VHDL实现时，分，秒，的显示，并能报时-Digital clock on the realization of VHDL to achieve with hour, minute, seconds display, and time