Fujitsu MHS2020AT, Руководство по эксплуатации продукта

Страница: 23 / 254

1.1 Features
C141-E171-03EN 1-3
1.1.3 Interface
(1) Connection to ATA interface
The MHS-series disk drives have built-in controllers compatible with the ATA
interface.
(2) 2 MB data buffer
The disk drives (the MHS Series) use a 2 MB data buffer to transfer data between
the host and the disk media.
In combination with the read-ahead cache system described in item (3) and the
write cache described in item (7), the buffer contributes to efficient I/O
processing.
(3) Read-ahead cache system
After the execution of a disk read command, the disk drive automatically reads
the subsequent data block and writes it to the data buffer (read ahead operation).
This cache system enables fast data access. The next disk read command would
normally cause another disk access. But, if the read ahead data corresponds to the
data requested by the next read command, the data in the buffer can be transferred
instead.
(4) Master/slave
The disk drives (the MHS Series) can be connected to ATA interface as daisy
chain configuration. Drive 0 is a master device, drive 1 is a slave device.
(5) Error correction and retry by ECC
If a recoverable error occurs, the disk drives (the MHS Series) themselves attempt
error recovery. The ECC has improved buffer error correction for correctable
data errors.
(6) Self-diagnosis
The disk drives (the MHS Series) have a diagnostic function to check operation of
the controller and disk drives. Executing a diagnostic function of the smart
command invokes self-diagnosis.
(7) Write cache
When the disk drives (the MHS Series) receive a write command, the disk drives
post the command completion at completion of transferring data to the data buffer
completion of writing to the disk media. This feature reduces the access time at
writing.