功能是检测出串行输入数据Sin中的4位二进制序列0101（自左至右输入），当检测到该序列时，输出Out=1；没有检测到该序列时，输出Out=0。-Function is to detect the serial input data Sin the 4-bit binary sequence 0101 (from left to right input), when the sequence is detected, the output Out = 1 the sequence is not