FUJITSU MCM3064AP - Manual (Page 44)

Specifications
2-12 C156-E227-01EN
During initialization, the user area is divided into several groups. Each of the
groups contains data sectors and spare sectors. Spare sectors are used as
replacements for defective data sectors. During initialization, the surface
inspection over the user area can be performed.
Figure 2.3 shows an example of alternate processing.
Figure 2.3 Example of alternate processing