Apparatus and method for detecting a sync pattern and an address mark within data provided from a recording medium

摘要

A disk apparatus for reproducing pulse width modulation (PWM) data from a disk is disclosed. A first sync pattern detector 26 compares data DTLE with a first sync pattern. A second sync pattern detector 29 compares data DTTE with a second sync pattern. A first signal generator 28 stops the detecting operation of the first detector when the first detector 26 has detected the first sync pattern from the data DTLE. A second signal generator 31 stops the detecting operation of the second detector when the second detector 29 has detected the second sync pattern from the data DTTE. A first time check circuit 32 restarts the detecting operation of the first detector when the first sync pattern has been detected first and the second sync pattern is not detected within a predetermined period of time. A second time check circuit 33 restarts the detecting operation of the second detector when the second sync pattern has been detected first and the first sync pattern is not detected within a predetermined period of time.