| 摘要 |
PURPOSE:To eliminate the influence of the operation of the drop-out compensator upon PCM, by deciding only input data of the second horizontal (H) period as error data if the same input data continues for 2H or more periods. CONSTITUTION:Data part D1 in 1H of the input data group is supplied to CRC operating circuit 2, and CRC check code part D2 in 1H is supplied to storage circuit 3 for the CRC check code preceding by 1H, CRC deciding circuit 4, and comparing circuit 5. Circuit 4 compares the CRC operation result with the CRC code and outputs ''0'' and ''1'' for coincidence between them and error respectively. The CRC code preceding by 1H from circuit 3 is compared with the current CRC code by 5; and when they coincide with each other, it is decided that the same data continues for 2H, and output ''1'' is sent to data latch 6. OR between output ''1'' of latch 6 and the output of circuit 4 is operated to obtain the data decision signal in 1H. |
