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2 logical address – FUJITSU MPE3XXXAT User Manual

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C141-E077-01EN

6 - 7

6.2.2

Logical 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).

LS

63

LH2

LH1

LH0

LS

2

LS

1

LS

1

408

407

406

190

189

64

63

62

3

2

36

35

1

1

127

126

Physical sector

Physical sector

ex: Zone 0

Physical parameter
- Physical sector: 1 to 406 (For the rest, 2 spare sectors)
Specification of INITIALIZE DEVICE PARAMETERS command
- Logical head: LH=0 to 14
- Logical sector: LS=1 to 63

Physical cylinder 0

Physical head 1

Physical cylinder 0

Physical head 0

LS

63

LS

1

LS

63

LS

1

SP

SP

LS

28

. .

. .

. .

. .

. .

. .

. .

. .

LS

63

LS

29

LS

1

LS

63

LS

1

LS

63

LS

1

LS

1

SP

SP

LS

63

. .

. .

. .

. .

. .

. .

. .

. .

. . . .

. . . .

. . . .

LH7

LH6

LH8

LH9

LH10

99

162

161

98

225

224

408

407

Figure 6.5

Address translation (example in CHS mode)