FIFO是英文First In First Out 的缩写，是一种先进先出的数据缓存器，他与普通存

储器的区别是没有外部读写地址线，这样使用起来非常简单，但缺点就是只能顺序写

入数据，顺序的读出数据，其数据地址由内部读写指针自动加1完成，不能像普通存

储器那样可以由地址线决定读取或写入某个指定的地址-FIFO is the abbreviation of the English First In First Out, a FIFO data buffer, the difference between ordinary memory is no external read and write address lines, so very simple to use, but the drawback is that the only order to write data sequential read data, the data address by the internal read and write pointer to automatically add one to complete, not like ordinary memory, as can be determined by the address lines to read or write to a specified address