Fujitsu MPD3XXXAT Spare area, Alternating defective sectors, 7 Sector slip processing, Defective

Models: MPD3XXXAT

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6.4.1Spare area

6.4.1Spare area

Following two types of spare area are provided in the user space.

1)Spare sector for sector slip:

used for alternating defective sectors at formatting in shipment in case that a physical track contains one or two defective sectors (2 sectors/track)

2)Spare cylinder for alternative assignment:

used for alternative assignment for the third and subsequent defective sectors in case that a physical track contains three or more defective sectors, and also used by automatic alternative assignment. (1 cylinder/drive)

6.4.2Alternating defective sectors

The two alternating methods described below are available:

(1)Sector slip processing

A defective sector is not used and is skipped and a logical sector address is assigned to the subsequent normal sector (physically adjacent sector to the defective sector).

When defective sector is present, the sector slip processing is performed in the formatting. Figure 6.7 shows an example where (physical) sector 5 is defective on head 0 in cylinder 0.

Index

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sector (physical)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

2

3

4

5

 

6

7

8

 

298406

 

 

407299

 

 

34008

 

 

 

 

Cylinder 0

 

 

 

 

 

 

 

Defective

 

 

 

 

 

 

 

 

 

 

 

 

SP

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Head 0

 

 

 

 

 

 

 

sector

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1

2

3

4

 

 

 

5

6

7

405

 

406

 

 

 

 

 

 

 

 

 

 

 

 

 

Sector (logical)

unused

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

If an access request to sector 5 is specified, the device accesses physical sector 6 instead of sector 5.

Figure 6.7 Sector slip processing

C141-E069-02EN

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Fujitsu MPD3XXXAT manual Spare area, Alternating defective sectors, 7 Sector slip processing, Defective