| 摘要 |
PURPOSE:To perform an data access with a high speed without giving an access to an undesired recording track, by storing a data block index tree data in the 1st storage device and at the same time storing a continuous and regular data access index data in the 2nd storage device respectively. CONSTITUTION:An instruction of an upper device is decoded through a control part 3 to control a track access control circuit 6, and a head 8 is positioned at the recording position of an optical disk 9 according to the contents of the 2nd or 1st storage device 2 or 1. When the head 8 is positioned at the continuous and regular data recording position, the access time is short each time to the disk 9 to increase the effect of the increment of other queuing time. To avoid this, the index data of the device 2 is used. When a data which is neither continuous nor regular is read, the head 8 is positioned on the track of the disk 9 by means of the index data of the device 1. Then the data is sent to an upper device through an interface circuit 4. |
