Fujitsu C141-E252-01EN 사용자 설명서

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C141-E252 

 

The size of the usable area for storing user data on the HDDs (format capacity) varies according to 
the logical data block or the size of the spare sector area.  Table 3.1 lists examples of the format 
capacity when the typical logical data block length and the default spare area are used.  The following 
is the general formula to calculate the format capacity. 

 

[Number of sectors of each zone] = [number of sectors per track 

×

 number of tracks per cell – 

number of alternate spare sectors per cell] 

×

 [number of cells in the zone] 

 

[Formatted capacity] = [total of sectors of all zones] 

÷

 [number of physical sectors in logical block] 

×

 

[logical data block length] 

 

The following formula must be used when the number of logical data blocks are specified with the 
parameter in the MODE SELECT or MODE SELECT EXTENDED command. 

 

[Format capacity] = [logical data block length] 

×

 [number of logical data blocks] 

 

The logical data block length, the maximum logical block address, and the number of the logical data 
blocks can be read out by a READ CAPACITY, MODE SENSE, or MODE SENSE EXTENDED 
command after initializing the disk. 

Model 

Data block length 

User blocks 

Format capacity (GB) 

MBA3300RC 

585, 937, 500 

300 (*) 

MBA3147RC 

287, 277, 984 

147 (*) 

MBA3073RC 

512 

143, 638, 992 

73.5 (*) 

(*)  One gigabyte (GB) = one billion bytes; accessible capacity will be less and actual capacity depends 

on the operating environment and formatting. 

 

Total number of spare sectors is calculated by adding the number of spare sectors in each primary 
cylinder and the number of sectors in the alternate cylinders. 

 
3.2 

 

The HDDs relate a logical data block address to each physical sector at formatting.  Data on the disk 
is accessed in logical data block units.  The initiator specifies the data to be accessed using the logical 
data block address of that data.