| 摘要 |
Each data read out from an optical disk is written into a RAM in response to a reproduced clock signal and then read out from the RAM in response to a reference clock signal. A decoder circuit detects a Run-out block in a data link period of the read-out data. Once such a Run-out block is detected, a timing resetting circuit compulsorily moves write and read pointers to the RAM to middle address and first address locations, respectively, of the RAM, so as to restore a distance between the two pointers to a predetermined basic distance corresponding to substantially half the total number of addresses of the RAM. With this arrangement, it is possible to avoid an overflow or underflow in the RAM that would result from the clock reproduction getting out of phase-locking by a phase locked loop during optical scanning in a data link period.
|
