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OEM MANUAL:K6602924
2 PRODUCT SPECIFICATION OUTLINE
Revision: 1 / Date: 2003.03.06
Page:
24
/ 273
Figure 2-1 explains the details of Track Skew.
Sector Sector Number
Head 0
Head 1
n sectors
Figure 2-1 Track Skew (Skew Factor n)
(6) Cylinder Skew
The controller implements Cylinder Skew which shifts the sector array between
cylinders ( i.e., between the last track of a cylinder and the first track of the next
cylinder) to avoid a rotational latency when a 1 track seek is performed.
Cyl m
Last Head
Cyl (m+1)
Head 0
n sectors
Figure 2-2 Cylinder Skew ( Skew Factor n )
When the skew factor n (the physical sector number between the last logical
block of a certain cylinder and the first logical block of the next cylinder)
corresponds to the 1 track seeking time, the continuous blocks over two cylinders
can be accessed with minimum rotational latency.
(7) Format Processing
The controller formats all data area and makes logical blocks accessible from the
host computer by FORMAT UNIT command in accordance with specified block
length, alternate spare area, defect management, sector interleave and skew
factor(s).
All data in the Data Area is deleted by executing the FORMAT UNIT command.
The controller identifies a sector which was specified by defect schemes ( P, D and
G schemes ) as defective, and assigns an alternate spare sector for the defective
sector.
0
1
2
N-1
N
2
3
4
0
1
0
-
-
N
-
0
1
-