Fujitsu MAX3073NC - SCSI,80, Dell DC961,Hard Drive Scsi Logical Interface Specifications page 99

b. Data block length
This field indicates the length (byte length) of 1 logical data block on the disk media.
(3) Page descriptor
The "Page descriptor" is configured from a parameter field which follows a 2-byte (4-byte for the sub
page format) page header, and is divided into units called "Page" for each parameter's functional
attributes. See the description of the MODE SELECT command (Section 3.1.5) concerning the
configuration of each page descriptor and their contents.
a. PS bit
When this bit is "1," the parameter value defined in that "Page descriptor" can be saved on the disk
media, and when it is "0", it indicates that this is a parameter which cannot be saved to the disk. It is
possible to save all the "Page descriptors" supported by the IDD. However, "1" is always indicated
in this bit for all "Page descriptors" transferred by this command.
b. SPF (sub page format)
A setting of "0" in this bit indicates that Page_0 Format (Short Page Format) is used. A setting of
"1" in this bit indicates that Sub_Page Format (Long Page Format) is used.
c. Page length
This field indicates the length of the parameter field (number of bytes) from byte 2 (4 for the sub
page format), excluding the page header of that "Page descriptor." The IDD always shows a value in
this field which is the same as the length defined in that "Page descriptor" regardless of the type of
parameter requested in the "PC (page control)" field of the CDB, and reports all the parameter fields
that "Page descriptor" in byte 2 and subsequent bytes.
d. Parameter field
The parameter field in byte 2 (4 for the sub page format) and subsequent bytes, indicates parameter
values of the type (current values, variable values, default values or save values) requested in the
"PC (page control)" field of the CDB. See the description of the MODE SELECT command
(Section 3.1.5) concerning the definition of each parameter, "Default" values and "Variable" values.
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3.1 Control/Sense Commands
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