Logical Address; Address Translation (Example In Chs Mode) - Fujitsu MPC3045AH Product Manual

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).
Physical sector
1
Physical cylinder 0
LS
1
Physical head 0
Physical sector
1
Physical cylinder 0
LS
Physical head 1 53
ex: Zone 0
Physical parameter
- Physical sector: 1 to 241 (For the rest, 2 spare sectors)
Specification of INITIALIZE DEVICE PARAMETERS command
- Logical head: LH=0 to 14
- Logical sector: LS=1 to 63
Figure 6.5
2 3 62 63 64
. . . .
LS LS LS
2 63 1
. . . .
LH0 LH1
11 12 74 75
. . . .
. .
LS LS LS LS
63 1 63 1
. . . .
. .
LH3 LH4 LH5

Address translation (example in CHS mode)

C141-E056-01EN
126 127 189 190 241
. . . .
LS LS LS LS LS
63 1 63 1 52
. . . .
LH2 LH3
137 138 200 201
. .
. . . .
LS LS LS LS
63 1 63 1
. . . . . .
. . . .
LH6
LH7
242 243
SP SP
242 243
SP SP
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