HP C737990900 Technical Reference Manual page 134

134 Commands
The operation was abandoned without status (that is, a bus release
occurred) after what the drive perceived was a catastrophic error or when
an error occurred following the drive's honoring of an
Following the bus release, the drive performed "cleanup" activity that
failed. The Deferred Error refers to the reason for this failure.
When any one of the above occurs, the sense generated will be
sense. This sense persists until the host sends a command that has Unit
ERROR
Attention as part of its pre-execution checks. When the Deferred Error pre-
execution check fails, the
and
CHECK CONDITION
to issue a
REQUEST SENSE
otherwise the data will be lost.
Write-Behind Deferred Errors:
If the Buffered Mode field of the
data buffering is enabled. If an error occurs in flushing the write-behind data,
sense is set for all hosts that the drive thinks have write-
DEFERRED ERROR
behind data in the buffer. For each of these hosts, the following occurs when its
next command is to be executed:
If the command is
copied to Current sense and the error is changed to a Current error (the
Error Code field is set to 70h). The information bytes will contain residue
information reflecting the size of the write-behind queue plus the transfer
size of the current command.
host reads sense data with a
with residue information indicating data lost for that write and
WRITE
previous writes.
If the command is not a write command and the Deferred Error check is
performed as part of the pre-execution checks,
reported. The
DEFERRED ERROR
sense is cleared. The host is expected to retrieve the sense
DEFERRED ERROR
by sending a
REQUEST SENSE
Bus Release Deferred Errors:
The drive will release the bus to terminate an operation (such as
the host sends an
ABORT
a catastrophic error.
In each case, the operation does not terminate immediately since the logical
position will have to be established on the other side of the block that was
sense is moved to the Current sense
DEFERRED ERROR
status is reported to the host. The host is then expected
command to recover the new Current sense data,
MODE SELECT
or
WRITE WRITE FILEMARKS
CHECK CONDITION
REQUEST SENSE
sense is copied to Current sense. The
, otherwise the data will be lost.
message or when the drive fails to send status due to
message.
ABORT
DEFERRED
parameter header is not zero,
the
DEFERRED ERROR
is reported. When the
, it will see an error for the
CHECK CONDITION
READ
sense is
status is
) when