The decoder is also divided into start detecting, clock recover, frame delimiter detecting, data decode, CRC checkout, decoding control and length error detecting units etc.

• 接收模块又划分为帧起始检测单元、时钟恢复单元、帧分界符检测单元、数据译码单元、CRC校验单元、译码控制单元和长度错误检测单元等。