Seagate ST3285N, Product Manual

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Byte 2
continued When the
Automatic Read Reallocation Enabled (ARRE)
bit is 1, the drive automatically reallocates bad blocks de-
tected while reading from the disc. When the ARRE bit is 0,
the drive does not automatically reallocate bad blocks.
Instead, a check condition status is reported with a sense
key of media error.
When the
Transfer Block (TB) bit is 1, the failing data block
is transferred to the initiator. When the TB bit is 0, the failing
data block is not transferred.
When the Read Continuous (RC) bit is 1, the drive sends
all data without doing any corrections. This function super-
sedes other bits in this byte. When the RC bit is 0, the
correction is performed according to the other bits in this
byte.
When the
Enable Early Recovery (EER) bit is 1, the drive
retries the command before applying ECC. When the EER
bit is 0, the drive applies ECC immediately. This bit applies
to data error recovery only; it does not affect positioning
retries and message system error recovery procedures.
When the Post Error (PER) bit is 1, the drive reports the
check condition status and the appropriate sense key for
any recovered errors encountered. When the PER bit is 0,
any errors recovered within the limits established by the
other error recovery flags are not reported. Any nonrecover-
able errors are reported.
The Disable Transfer on Error (DTE) bit is valid only when
the PER bit is set to 1. When the DTE bit is 1, the drive
terminates data transfer if a recoverable error occurs. When
the DTE bit is 0, the drive continues transferring data if
recoverable errors are encountered.
When the Disable Correction (DCR) bit is 1, the drive does
not apply ECC to the data even if correction is possible.
Byte 3 The
read retry count field is the maximum number of times
the drive attempts its recovery algorithms. If the EER bit
is 1, the number of retries specified by read retry count (up
to a maximum of nine retries) is performed before ECC is
applied. The read retry count field has a range of 0
through 20
H
. A read retry count of 0 means that no retries
are performed.
Byte 4 The correction span is the size of the largest read data error,
in bits, on which ECC correction is attempted. Longer errors
are reported as nonrecoverable.
92 ST3655 Family SCSI Drives Product Manual, Rev. A