Write Extended (2A) - IBM Ultrastar 36LZX Specifications

8.43 WRITE EXTENDED (2A)

Byte
7 6
0
1 Reserved = 0
2 (MSB)
3
4
5
6
7 (MSB
8
9 VU = 0
Figure 162. WRITE EXTENDED (2A)
The WRITE EXTENDED command requests that the drive write the data transferred from the initiator.
This command is processed like the standard WRITE command except for the longer transfer length.
Transfe The number of contiguous blocks to be transferred. If the transfer length is zero, the seek
length occurs, but no data is transferred. This condition is not considered an error.
DPO A DPO (Disable Page Out) bit of one indicates that the data accessed by this command is to
be assigned the lowest priority 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. A FUA 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.
RelAdr Relative Block Address is not supported. Must be set to zero.
Bit
5 4 3
Command Code = 2Ah
DPO FUA
Logical Block Address
Reserved = 0
Transfer Length
Reserved = 0
Ultrastar 36LZX hard disk drive specifications
2 1 0
Reserved RelAdr
= 0 = 0
(LSB)
(LSB)
FLAG LINK
185