| 摘要 |
PURPOSE:To facilitate the processing of s cynchronizing pattern interposed between data blocks and to perform the demodulation processing of CMT at the program level of a microcomputer by using a special pattern which does not appear in normal data as the 1st pattern of a record, and using another special pattern which appears in normal data as synchronizing patterns in the middle. CONSTITUTION:The 1st synchronizing pattern FSY of a record following a preamble PREA consists of the special pattern which does not appear in normal data and resynchronizing patterns SYNC among data blocks 10, 11... in the middle of the record consist of the specific bit pattern (''F9''=''11111001'') which appears in normal data. When records being to be read, a one-chip microcomputer 14 detects the 1st FSYN of the record after detecting the PREA. In this case, the microcomputer 14 has a margin of processing because data blocks are not read yet, and the processing ability is assigned to the detection of FSYN, and data blocks of every frame are read correctly in a readout routine. |
