此为我们组在学校比赛中设计的多功能计数器的系统设计文档，此多功能计数器即是测频测相器（硬件使用EPM240采样和计数，mega16取数和控制）-This is our group s multi-purpose counter system design documents in school competitions. This multi-function counter that is the frequency and phase detector(hardware using EPM240 sampling and counting, mega16 take the count number and control).