Hitachi ULTRASTAR 15K450 HUS154530VLF400 - Manual (Page 297)

Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
281
19.51 WRITE (10) - (2A)
Table 239: WRITE (10) - (2A)
The WRITE (10) command requests that the drive write the data transferred from the Initiator. This command is processed like
the standard WRITE (6) - (0A) command except for the longer transfer length.
• Transfer Length is the number of contiguous blocks to be transferred. If the transfer length is zero, the seek occurs,
but no data is transferred. This condition is not considered an error.
• DPO (Disable Page Out) bit of one indicates that the data accessed by this command is to be assigned the lowest pri-
ority for being written into or retained by the cache. A DPO bit of one overrides any retention priority specified in the
Mode Select Page 8 Caching Parameters. A DPO bit of zero indicates that the priority is determined by the retention
priority. The Initiator should set the DPO bit when the blocks written by this command are not likely to be read in the
near future.
• FUA (Force Unit Access) bit of one indicates that the Target must write the data to the media before returning Good
status. A FUA bit of zero indicates that the Target may return Good status prior to writing the data to the media.
• FUA_NV (Force Unit Access Non-Volatile Cache) may be set to 0 or 1, but is ignored since NV_SUP=0 in Inquiry
Page 86h.
If a WRITE(6) command is received after protection information is enabled, the drive will set the protection information as
follows as it writes each block to disk:
• the Logical Block Guard field is set to a properly generated CRC
• the Logical Block Reference Tag field is set to:
• the least significant four bytes of the LBA, if the RTO_EN bit is set to zero in the READ CAPACITY (16)
parameter data ; or
• FFFFFFFFh, if the RTO_EN bit is set to one;
• the Logical Block Application Tag field is set to
• FFFFh, if the ATO bit is set to one in Mode Page 0Ah
• Any value, if the ATO bit is set to zero.
WRPROTECT defines the manner in which protection information written to disk shall be checked during processing of the
command. Protection information may be transmitted to the drive with the user data, based on the WRPROTECT bit and the
drive format.
Byte
Bit
7 6 5 4 3 2 1 0
0 Command Code = 2Ah
1 WRPROTECT DPO FUA Rsvd=0
FUA_N
V
Obso-
lete
2-5
(MSB)
Logical Block Address
(LSB)
6 Reserved = 0
7-8
(MSB Transfer Length
(LSB)
9 VU = 0 Reserved = 0 FLAG LINK