在远距离数据通信中，为确保高效而无差错地传送数据，必须对数据进行校验即差错控制。循环冗余校验CRC(Cyclic Redundancy Check)是对一个传送数据块进行校验，-In the long-distance data communications, in order to ensure the efficient transmission of data without errors, we must check the data that the error control. C