Product manual

SCSI Description
Maxtor Atlas 10K IV 5-39
5.14.2 Mode Page Types
The drive maintains three distinct sets of mode pages. They are the current page,the
default page,andthesaved page. The drive also reports a fourth set of changeable
pages. The page types are defined in Table 5-52.
Table 5-52 Mode Page Types
5.14.3 Mode Parameter List
Table 5-53 shows the format of the Mode Parameter List that is passed by the initiator
to the drive during the command’s data-out buffer transfer. Table 5-54 describes the
fields. Table 5-55 and Table 5-56 provides a description of the data format and fields
of the Mode Parameter Header. Table 5-57 and Table 5-58 describe the format and
field descriptions for the Mode Parameter Block Descriptor.
Table 5-53 Mode Parameter List-Data Format
Page Type Definition
Current
The current mode page set applies to all initiators and defines the drive’s mode. The SCSI-2 spec-
ification states that a drive can maintain Mode parameters on a per-initiator basis if it so chooses.
The Drives do not support this option.
The current mode page set contains the values supplied in the last MODE SELECT command re-
ceived from an initiator. If no initiator has sent a MODE SELECT command since the drive was
last reset or powered up, the current pages contain
• Saved values if saved pages exist (from a previous MODE SELECT command SP parameter).
• Default values if pages have never been saved.
The drives generate a Unit Attention condition for all initiators (except for the one that was the
source of the MODE SELECT command) whenever one initiator modifies the Mode parameters.
Default
The default mode page set contains the factory default values thatare listed in each page’s descrip-
tion.
Saved
The saved mode page set contains values preserved in the drive’s non-volatile memory by a pre-
vious SP-modified MODE SELECT command.
Changeable
The changeable mode page set provides a means for an initiator to determine which pages it is
allowed to change and the specific bits within those pages that it is allowed to change. This page
set is read-only and is fetched with a MODE SENSE command.
Bit
Byte
765 4 3210
0 – 3 Mode Parameter Header
4–11
Block Descriptor
(optional)
4–n
or
12–n
Page(s)
(optional)