代码满足所有AD7416系列执行时的时序要求

AT89CX051微控制器，一个6 MHz的时钟。代码的修改可能

如果需要更快的时钟取代。-The code meets all ad7416 family timing requirements when executed by an

　AT89Cx051 microcontroller with a 6 MHz clock. Code modifications may be

　required if a faster clock is substituted.