同步FIFO设计一个同步FIFO，该FIFO深度为16，每个存储单元的宽度为8位，要求产生FIFO为空、满、半满、溢出标志。请采用可综合的代码风格进行编程。-Synchronous FIFO design a synchronous FIFO, the FIFO depth is 16, the width of each memory cell is 8, required to generate the FIFO is empty, full, half full, the overflow