Chapter 4 SCSI Commands
MODE SENSE (6) / (10) Command (1Ah / 5Ah)
DLT-S4 Interface Reference Guide
178
RBO
Recover Buffer Order. Always set to 0.
REW
Report Early Warning. Always set to 0 (do not report Early Warning EOM on
READ
).
Gap Size
Always set to 0.
EOD Defined
End of Data. Always set to 0h.
EEG
Enable EOD Generation. When set to 1, indicates that the drive generates an EOD.
The drive generates an EOD mark before any change of direction following a
WRITE
-type operation.
SEW
Synchronize at Early Warning. When set to 1, the drive writes any unwritten data
or tapemarks to the medium before each command completes once the End of
Medium early warning point is reached, effectively operating as if in unbuffered
mode. When set to 0, the drive continues to operate in buffered mode, if enabled,
past the End of Medium early warning point. Default value is 1.
SWP
Software Write Protection. Always set to 0.
Buffer Size at Early
Warning
Always set to 0.
Select Data
Compression
Algorithm
If set to 1, data compression is enabled. If set to 0, data compression is disabled.
OIR
If the only if reserved (OIR) bit is set to one, the device server will process a
command only if a reservation (see
SPC-2
) or persistent reservation (see
SPC-3
)
exists that allows access via the I_T nexus from which the command was received.
If the OIR bit is set to one and a command is received from an I_T nexus for which
no reservation exists, the device server will not process the command. If the OIR
bit is set to one and a command is received from an I_T nexus for a logical unit
upon which no reservation or persistent reservation exists, the device servers
terminates the command with
CHECK CONDITION
status. The sense key is set to
ILLEGAL REQUEST
and the additional sense code is set to
NOT RESERVED
.
Commands that are not be effected by the OIR bit set to one are defined as
Allowed in the presence of persistent reservations in
SPC-3
, or are defined in
SPC-
2
as Allowed in the presence of reservations. Commands that are effected by the
OIR bit set to one are defined as Conflict in the presence of persistent reservations
in
SPC-3
, except for the
RESERVE, RELEASE
,
PERSISTENT RESERVATION IN
, and
PERSISTENT RESERVATION OUT
commands, or are defined in SPC-2 as Conflict in
the presence of reservations. An OIR bit set to zero specifies the device server will
process commands as specified in SPC-3.
Field
Description