6.2.2Logical address

(1)CHS mode

Logical address assignment starts from physical cylinder (PC) 0, physical head (PH) 0, and physical sector (PS) 1 and is assigned by calculating the number of sectors per track which is specified by the INITIALIZE DEVICE PARAMETERS command. The head address is advanced at the subsequent sector from the last sector of the current physical head address. The first physical sector of the subsequent physical sector is the consecutive logical sector from the last sector of the current physical sector.

Figure 6.5 shows an example (assuming there is no track skew).

Physical sector

1 2 3

Physical cylinder 0

LS1

Physical head 0

LH0

Physical sector

 

1

 

Physical cylinder 1

LS

 

 

 

Physical head 0

49

 

 

 

62

63

64

 

 

126

127

 

 

 

 

 

 

 

 

 

 

LS

LS1

 

 

 

LS

LS1

 

 

 

 

 

 

63

 

 

 

63

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LH1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LH2

 

15

16

 

 

78

79

 

 

 

 

 

 

 

 

 

LS

LS1

 

 

 

LS

LS1

LS2

 

 

 

63

 

 

 

63

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

299 300

LS LS

4748

LH4

LH4

LH5

LH6

ex: Zone 0

Physical parameter

– Physical sector: 1 to 300

Specification of INITIALIZE DEVICE PARAMETERS command

Logical head: LH = 0 to 14

Logical sector: LS = 1 to 63

Figure 6.5 Address translation (example in CHS mode)

C141-E045-02EN

6 - 7

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Fujitsu MPB3052AT, MPB3054AT, MPB3032AT, MPB3021AT, MPB3043AT Logical address, LH0, LS1 LH1 LH2 LS2, LS LS LH4 LH5 LH6