IBM IC35L018UCDY10, Specifications

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8.10 MODE SELECT (6) (15h)
LINK FLAG Reserved = 0 VU = 0 9
Parameter List Length 4
Reserved = 0
2
3
SP Reserved = 0 PF=1 Reserved = 0 1
Command Code = 15h 0
0 1 2 3 4 5 6 7
Bit
Byte
Figure 105. MODE SELECT (6)
The MODE SELECT (6) command provides a means for the initiator to specify LUN or device parameters
to the drive. It also allows an Initiator to specify options the drive uses in error recovery and caching.
There is a single set of Mode Page parameters shared by all initiators.
!
PF (Page Format) bit value of one indicates that the data sent by the Initiator after the Mode Select
Header and the Block Descriptor, if any, complies to the Page Format. The drive ignores this field
since it accepts only mode parameters in the Page Format.
!
SP Pages. This indicates
0 The drive shall not save the pages sent during the DATA OUT phase but will use them for
all following commands until the power is removed, a reset is received, or a new MODE
SELECT command is received.
1 The drive will save the data in the reserved area of the disk. It will be used for all the
following commands until another MODE SELECT command is issued. This information
is maintained over a power cycle or reset of the drive.
!
Parameter List Length specifies the number of bytes to be sent from the initiator. A parameter list
length of zero suppresses data transfer and is not considered as an error.
The MODE SELECT parameter list contains a four-byte header which is followed by zero or one block
descriptor followed by zero or more pages. The pages which are valid with this command are defined in
Sections 8.8.2 to 8.8.13 beginning on page 85.
Application Note
The initiator should issue a MODE SENSE command requesting all Changeable values (see PCF field in
byte two of the CDB in Section 8.8, "Mode Sense (6)(1A)" on page 80) prior to issuing a MODE SELECT
command. This is necessary to find out which pages are implemented by the drive and the length of those
pages. In the Pages of the MODE SENSE command the drive will return the number of bytes supported
for each Page. The Page Length set by the initiator in the MODE SELECT command must be same value
as returned by the drive in MODE SENSE Page Length. If not, the drive will return CHECK CONDITION
status with sense key of ILLEGAL REQUEST.
Note: If an initiator sends a MODE SELECT command that changes any parameters that apply to other
initiators, the drive generates a unit attention condition for all initiators except for the one that issued the
MODE SELECT command. The drive shall set the additional sense code to PARAMETERS CHANGED
(2Ah).
Ultrastar 146Z10 hard disk drive specifications
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