Seagate SCSI Interface Product Manual page 143

SCSI Interface Product Manual, Rev. J
Notes.
[1] The only time this page of parameters may be sent is immediately before sending a Format Unit com-
mand to the drive. The Current parameters for this page are updated immediately but any changes
between these Current parameters and the existing media format are not in effect until after the Format
Unit command is completed. A PS bit of 1 indicates this page is savable. The PS bit is not used with the
Mode Select command.
[2] The Tracks per Zone field indicates the number of tracks the drive allocates to each defect management
zone. A zone can be one or more tracks or one or more cylinders. See individual drive's Product Manual,
Volume 1, for number of tracks allocated to each defect management zone for that drive model.
[3] The Alternate Sectors per Zone field indicates the number of spare sectors to be reserved for the defined
defect management zone. A value of zero indicates that no sectors are to be reserved in each zone for
defect management. This is to accommodate hosts that want to manage the defects themselves.
[4] The Alternate Tracks per Zone field indicates the number of spare tracks to be reserved at the end of each
defect management zone. A value of zero indicates that no spare tracks are to be reserved in each zone
for defect management by the drive.
[5] The Alternate Tracks per Volume field indicates the number of spare tracks to be reserved at the end of
the drive volume. The drive uses these locations for replacing defective sectors. A value of zero indicates
that no spare tracks are to be reserved at the end of the unit for defect management. The initiator may
change this value for a number between 0 and 255 that is a multiple of the total number of Data Read/
Write heads installed. However, it is not changeable on some products.
[6] The Sectors per Track field indicates the average number of physical sectors the drive has per disc track.
This value depends on the selected sector size and ZBR zones. The number of user accessible sectors
per track may be fewer than the reported value, since sectors per Track includes sectors set aside for
defect management. This value cannot be used to calculate drive user accessible capacity.
Note. The value cannot be directly selected with the Mode Select command, but is a report of how the
drive is configured.
[7] The Data Bytes per Physical Sector field indicates the number of data bytes the drive shall allocate per
physical sector. This value equals the block length reported in the Mode Sense block descriptor. The bytes
per physical sector is not directly changeable by the initiator and is not verified on a Mode Select com-
mand.
[8] The Interleave field is the interleave value sent to the drive during the last Format Unit command.
Note. This field is valid only for Mode Sense commands. The drive ignores this field during Mode Select
commands.
[9] The Track Skew Factor field indicates the average number of physical sectors between the last logical
block on one track and the first logical block on the next sequential track of the same cylinder. A value of
zero indicates no skew.
Note. This value is not changeable by an initiator.
[10] The Cylinder Skew Factor field indicates the average number of physical sectors between the last logical
block of one cylinder and the first logical block of the next cylinder. A value of zero indicates no skew. Cyl-
inder skew will be utilized by a drive but is not changeable by an initiator.
[11] The Drive Type field bits are defined as follows:
The Hard Sectoring (HSEC) bit (bit 6) set to one indicates the drive shall use hard sector formatting.
Bits 0-5, and 7 are not implemented by the drive and are always zero. All bits (0-7) are not changeable.
[12] See individual drive's Product Manual, Volume 1, Mode Sense Data section for changeable values.
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