Fujitsu MAX3073NC - SCSI,80, Dell DC961,Hard Drive Scsi Logical Interface Specifications page 281

Remark:
1. When this function is specified (ARRE = "1"), the EER flag's specification in the MODE
SELECT parameter is made invalid and Read retry processing is performed up to the number of
times specified in the "Number of Retries during Read" parameter. If "0" is specified in the
DCR flag, correction processing of the data is performed afterward (see Section 5.3.1 (3)).
When "1" is specified in the DCR flag, ECC correction processing is prohibited, so even if "1"
is specified in the ARRE flag, auto alternate block allocation processing will not be executed for
errors in the data area.
2. When errors in the data area are recovered from by ECC correction processing, before
implementing alternate block allocation processing, rewriting of the recovered data and a verify
check (rereading) are performed. If data are recovered by rewriting, alternate block allocation
of that data block is not performed.
3. When a write operation is prohibited through the setting terminal, the auto alternate block
allocation processing specification is disabled.
(2) Auto alternate block allocation processing during a write operation 1
This function is enabled by specifying "1" in the AWRE flag in the MODE SELECT parameters.
Furthermore, this function is applicable to the following commands only.
• WRITE command
• WRITE EXTENDED command
• WRITE AND VERIFY
If a WRITE command has the same LBA in the log, then data will be written to the sector, and it will be
verified. If the verify is successful, then the AWRE will not be performed. (no sense will be reported).
If the verify is unsuccessful, then check the spare. Write the data onto the new spare, and verify it. If the
verify is successful, then the reallocation will be proceeded. If the verify is unsuccessful, then the drive
will add the defective spare onto the G-List, and then its conversion process will be interrupted. After
reallocates all of the logged LBA included in a WRITE command the drive will start the write operation.
(3) Auto alternate block allocation processing during a write operation 2
This function is enabled by specifying "1" in the AWRE flag in the MODE SELECT parameters.
Furthermore, this function is applicable to the following commands only.
• WRITE command
• WRITE EXTENDED command
• WRITE AND VERIFY
When this function is permitted, if, during WRITE/WRITE EXTENDED command detects any Servo
error (e.g. Write offtrack error) and cannot be recovered within pre-determined retry number (specified
in Mode Parameter). For the sectors around defective Servo, alternate blocks are allocated and the data
of this WRITE commands are re-written.
C141-C010
5.3 Disk Drive Error Recovery Processing
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