| 摘要 |
PURPOSE:To prevent the missing of data in advance and to improve the reliability of the titled device by providing a write clock signal detecting circuit confirming whether or not a write clock signal is received ahead the write. CONSTITUTION:The read/write clock signal forming circuit 15 of a disc device generates a read/write clock signal in synchronizing with a VFO clock signal and gives it to a disc controller. When the write clock signal detecting circuit 17 receives a write clock signal WC before a write instruction WT, the output of an FF26 is logical 0 and the output AL of an FF27 is logical 0, then no alarm is raised. When the write clock signal WC is not received before a write instruction WT' delayed from a delay circuit 25 is not given with a prescribed time elapsed after the write instruction WT is received, the output of the FF26 is logical 1 and the output AL of the FF27 is logical 1, then the alarm signal is generated and the control circuit 12 processes write inhibition. |
