Logical Address; Address Translation (Example In Chs Mode) - Fujitsu MPG3xxxAT 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
31
Physical head 1
LH13
ex: Zone 0
Physical parameter
- Physical sector: 1 to 798 (For the rest, 2 spare sectors)
Specification of INITIALIZE DEVICE PARAMETERS command
- Logical head: LH=0 to 15
- Logical sector: LS=1 to 63
Figure 6.5
2 3 62 63 64
. . . .
LS LS LS
2 63 1
. . . .
LH0 LH1
97
. . 33 34 . . 96
. .
LS LS LS LS
63 1 63 1
. . . .
. .
LH14 LH15

Address translation (example in CHS mode)

C141-E110-02EN
126 127 189 190 796
. . . .
LS LS LS LS LS
63 1 63 1 28
. . . .
LH2
159 160 . . 222 223
. . . .
LS LS LS LS
63 1 63 1
. . . . . .
. . . .
LH16
LH1
797 798
LS LS
29 30
797 798
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