| 摘要 |
During a "Burst Read Mode", an optical storage device reads data from a medium into a buffer faster than a host device reads data out from the buffer. To improve power efficiency, the optical storage device powers down read/write components when a buffer fills to a first level. The read/write components include the optical pickup unit, the spindle motor, the actuator motor, their associated electronics, and the system microprocessor. While the read/write components are powered down, the host device continues to read data out of the buffer. When the output buffer empties to a second level, a buffer logic wakes up the system microprocessor and the system microprocessor powers up the read components. During a "Burst Write Mode", the host device reads data into the buffer slower than the optical storage device reads data out from the buffer to write the data to medium 3. To improves power efficiency, the optical storage device powers down read/write components when the buffer empties to a third level. While the read/write components are powered down, the host device continues to read data into the buffer. When the buffer fills to a fourth level, the buffer logic wakes up the system microprocessor and the system microprocessor powers up the write components. The optical storage device also transitions from one power state to another when a host device has not accessed the storage device within a specified time. In each transition, optical storage device powers down more and more read/write components until all the read/write components are powered down. Furthermore in the last power state, the buffer, which also stores the file system information from the medium, is also powered down. |
