Seagate ST3285N, Product Manual

Page: 119 / 151

Byte 2 The
notched drive (ND) bit is always 1, which means the
disc contains notches of different recording densities. For
each supported active notch value, this page defines the
starting and ending boundaries of the notch.
The logical or physical notch (LPN) bit is 0, which means
the notch boundaries are based on the physical parame-
ters of the logical unit. The cylinder is most significant; the
head is least significant.
Byte 3 Reserved.
Bytes 4–5 The
maximum number of notches field indicates the maxi-
mum number of notches supported by the drive.
Bytes 6–7 The
active notch field identifies the notch to which this,
and all future Mode Select and Mode Sense commands
refer, until the active notch is changed by a later Mode
Select command. The value of the active notch field must
be greater than or equal to 0 and less than or equal to the
maximum number of notches. An active notch value of 0
means that current and future Mode Select and Mode
Sense commands refer to the parameters that apply for
all notches.
Bytes 8–11 The starting boundary field indicates the beginning of the
active notch, if the active notch is not 0, or the starting
boundary of the logical unit, if the active notch is 0. This
field is ignored by the Mode Select command.
When the LPN bit is 0, the three most significant bytes
represent the cylinder number and the least significant
byte represents the head number.
Bytes 12–15 The ending boundary field indicates the end of the active
notch, if the active notch is not 0, or the end of the logical
unit, if the active notch is 0. The default is equal to the end
of zone 1.
When the LPN bit is 0, the three most significant bytes
represent the cylinder number and the least significant
byte represents the head number.
Bytes 16–23 The pages notched field contains a bit map of the mode
page codes that indicates which pages may contain dif-
ferent parameters for each notch. When a bit is 1, the
corresponding mode page can contain different parame-
ters for each notch. When a bit is 0, the corresponding
mode page contains the same parameters for all the
notches. The most significant bit of this field corresponds
to page code 3F
H
and the least significant bit corresponds
to page code 00
H
.
ST3655 Family SCSI Drives Product Manual, Rev. A 109