说明：  软件模拟CRC冗余校验，可以对任意长度的发送序列求16位校验和，并且可以对接收序列进行检查。有详细的中文注释，和模拟函数
(simulation software CRC Redundancy Check, for any length of this sequence for 16 checksum, and to be able to receive sequence for the examination. The Chinese have detailed notes and simulation function)