Caching Parameters); Page - IBM DCAS-32160 - Ultrastar 2.1 GB Hard Drive Specifications

7.12.7 Page 8 (Caching Parameters)
7 6
BYTE 0 PS RSVD=0
BYTE 1
BYTE 2
BYTE 3 Read Retention Priority=0
BYTE
4 5
BYTE
6 7
BYTE
8 9
BYTE
10 11
BYTE 12
BYTE 13
Figure 81. Page 8
Changeable Parameter
WCE
MF
RCD
| Disable Pre-fetch transfer length
Minimum Pre-fetch
| Maximum Pre-fetch
| Maximum Pre-fetch Ceiling
Number of Cache Segments
The caching parameters page defines parameters that affect the use of the cache.
WCE, Write Cache Enable bit, is set to zero to indicate that the drive must issue Good Status for
Write(6) or Write extend(10) command only after successfully writing the data to the media. A WCE bit
of one indicates that the drive may issue Good Status for a Write(6) or Write extend(10) command after
successfully receiving the data but before writing it to the media.
Note: When WCE = 1, a Synchronize Cache command must be done to assume data is written to the
media before powering down the Target.
BIT
5 4 3
Page Code = 08h
Page Length = 0Ch
RESERVED = 0
Write Retention Priority=0
Disable Pre fetch Transfer Length
Minimum Pre fetch
Maximum Pre fetch
Maximum Pre fetch Ceiling
RESERVED = 0
Number of Cache Segments
Default Value
1
0
0
F F F F h
0
F F F F h
F F F F h
7
2 1 0
WCE MF RCD
SCSI C O M M A N D SET
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