对20MHZ时钟进行分频。之后用分频后的频率作为时钟信号同步后级的模16计数器。4位计数器输出信号可以用来控制MUX进行数据通道的定时采集。-To 32 magnitude optional 20 MHZ clock frequency division.After using crossover frequency as the clock signal synchronization after level 16 counter modules.Four counter output signal can be used to control the MUX timing acquisition of data channel.