Alternating Processing For Defective Sectors - Fujitsu MHS2030AT - 2.5" Notebook 30GB Drive Product Manual

Operations

6.3.2 Alternating processing for defective sectors

The following two types of technology are used for alternating processing:
(1) Sector slip processing
In this method, defective sectors are not used (thereby avoiding the effects of
defects), and each defective sector is assigned to the next contiguous sector that is
normal.
Depending on the format defined at shipment from the plant, this processing is
performed for defective sectors.
Figure 6.5 shows an example where sector (physical) 5 with cylinder 0 and head 0
is defective.
Sector (physical)
Cylinder 0
Head 0
Note: When an access request for sector 5 is issued, physical sector 6 must be
accessed instead of physical sector 5.
(2) Alternate cylinder assignment processing
This technology assigns a defective sector to a spare sector of an alternate
cylinder.
This processing is performed when automatic alternating processing is attempted
for a physical track that contains three or more defective sectors.
Figure 6.6 shows an example where alternate cylinder assignment processing is
applied to sector (physical) 5 with cylinder 0 and head 0.
6-10
Defec-
tive
sector
(Not used)
Figure 6.5 Sector slip processing
C141-E171-03EN