1.1 Standard Features

(7)Cache feature

After executing the READ command, the HDD reads automatically and stores (prefetches) the subsequent data blocks into the data buffer (Read-ahead caching).

The high speed sequential data access can be achieved by transferring the data from the data buffer without reaccessing the disk in case the subsequent command requests the prefetched data blocks.

The Write Cache feature is supported. When this feature is enabled, the status report is issued without waiting for completion of write processing to disk media, thereby enabling high speed write processing.

When Write Cache is enabled, you should ensure that the cached data is surely flushed to the disk media before you turn off the drive's power.

To ensure it, you should issue either the SYNCHRONIZE CACHE command or the STOP UNIT command with specifying “0” to the Immediate bit, and then confirm that the command is surely terminated with the GOOD STATUS.

(8)Command queuing feature

The HDD can queue maximum 128 commands, and optimizes the issuing order of queued commands by the reordering function. This feature realizes the high speed processing.

(9)Reserve and release functions

The HDD can be accessed exclusively in the multi-host or multi-initiator environment by using the reserve and release functions.

(10)Error recovery

The HDD can try to recover from errors in the disk drive using its powerful retry processing. If a recoverable data check occurs, error-free data can be transferred to the initiator after being corrected in the data buffer. The initiator software is released from the complicated error recover processing by these error recovery functions of the HDD.

(11)Automatic alternate block reassignment

If a defective data block is detected during read or write the HDD can automatically reassign its alternate data block.

(12)Programmable data block length

Data can be accessed in fixed-block length units. The data block length is programmable, and can be specified at initializing with a multiple of four within the range of 512 to 528 bytes.

C141-E219

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Fujitsu MAV2036RC, MAV2073RC manual Standard Features