Fujitsu MAS3184NC - Enterprise 18.4 GB Hard Drive, Product/Maintenance Manual

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(8) Command queuing feature
The IDD 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 IDD can be accessed exclusively in the multi-host or multi-initiator environment by using the
reserve and release functions.
(10) Error recovery
The IDD can try to recover from errors in SCSI bus or 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 IDD.
(11) Automatic alternate block reassignment
If a defective data block is detected during read or write the IDD 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.
IMPORTANT
Error rate increase
1. The drive format at factory shipment is generally 512 byte.
2. The Recoverable Error of the drive might increase when the
format would be modified from 512 bytes to the following values:
516 bytes, 520 bytes, 524 bytes, 528 bytes.
3. The Recoverable Error referred to here is sense data (1-13-xx).
(13) Defective block slipping
A logical data block can be reallocated in a physical sequence by slipping the defective data block
at formatting. This results in high speed contiguous data block processing without a revolution
delay due to defective data block.
(14) High speed positioning
A rotary voice coil motor achieves fast positioning.