Manualshelf

User Manual

ManualsBrandsSeagate Bulk ManualsSeagate Bulk Hard Drives & Storage4TB ENT CAP 3.5 HDD SATA 7200 RPM 128MB 3.5IN
251252253254255256257258259260
SCSI Commands Reference Manual, Rev. J 252
www.seagate.com Direct Access Block commands (SPC-5 and SBC-4)
FUA bit
0 A Force unit Access (FUA) bit set to zero specifies that the device server shall write the logical blocks to volatile cache (if any), non-vola-
tile cache (if any), or the medium.
1 An FUA bit set to one specifies that the device server shall write the logical blocks to non-volatile cache (if any) or the medium.
If logical blocks are transferred directly to a cache, the device server may return GOOD status prior to writing the logical blocks to
the medium. Any error that occurs after the GOOD status is returned is a deferred error, and information regarding the error is
not reported until a subsequent command.
TRANSFER LENGTH field
The TRANSFER LENGTH field specifies the number of contiguous logical blocks of data that shall be transferred from the data-out buffer and
written, starting with the logical block specified by the LOGICAL BLOCK ADDRESS field. A TRANSFER LENGTH field set to zero specifies that no
logical blocks shall be written. This condition shall not be considered an error. Any other value specifies the number of logical blocks that shall
be written. If the logical block address plus the transfer length exceeds the capacity of the medium, the device server shall terminate the com
-
mand with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST and the additional sense code set to LOGICAL BLOCK
ADDRESS OUT OF RANGE. The TRANSFER LENGTH field is constrained by the MAXIMUM TRANSFER LENGTH field in the Block Limits VPD page.
RWWP interaction
If the device server has knowledge of the contents of the LOGICAL BLOCK APPLICATION TAG field and the ATO bit is set to one in
the Control mode page (see SPC-5), then the device server:
a) may check each logical block application tag if the RWWP bit is set to zero in the Control mode page (see SPC-5); and
b) shall check each logical block application tag if the RWWP bit is set to one in the Control mode page.
If the ATO bit in the Control mode page (see SPC-5) is set to one, then this knowledge is acquired from:
a) the EXPECTED LOGICAL BLOCK APPLICATION TAG field and the LOGICAL BLOCK APPLICATION TAG MASK field in the CDB,
if a WRITE(32) command
(see 3.63), a WRITE ATOMIC (32) command (see 3.69), a WRITE SAME (32) command (see 3.75), or
a WRITE STREAM (32) command (see 3.77) is received by the device server;
b) the EXPECTED LOGICAL BLOCK APPLICATION TAG field and the LOGICAL BLOCK APPLICATION TAG MASK field in each LBA
range descriptor, if a WRITE SCATTERED (32) command (see SBC-4), is received by the device server;
c) the Application Tag mode page (see 5.3.6), if a command other than WRITE(32), WRITE ATOMIC (32), WRITE SAME (32),
WRITE SCATTERED(32), or WRITE STREAM (32) is received by the device server and the ATMPE bit in the Control mode page
(see SPC-5) is set to one; or
d) a method not defined by this standard, if a command other than WRITE(32), WRITE ATOMIC (32), WRITE SAME (32), WRITE
SCATTERED(32), or WRITE STREAM (32) is received by the device server, and the ATMPE bit is set to zero.