A basic circuit and its software flow for UHF and VHF fequency measuring are designed in this paper. According to the basic theory of frequenay measuring,the method of frequeney is external|event|interrupt,not traditional timer|interrupt.

• 根据频率测量的基本原理 ；采用外部事件中断而不是常规的定时中断的频率测量的工作方式 ；设计了特高频 UHF；甚高频 VHF频率测量的基本电路和软件流程 .