Logical Address; Address Translation (Example In Chs Mode) - Fujitsu MPB3021AT 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
LS1
Physical head 0
Physical cylinder 1
Physical head 0
Figure 6.5
2 3 62 63
LH0
Physical sector
1 15 16
LS LS
LS1
49 63
LH4
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

Address translation (example in CHS mode)

C141-E045-02EN
64
126
LS LS
LS1 LS1
63 63
LH1
78 79
LS
LS1 LS2
63
LH5
127 299 300
LS LS
47 48
LH2 LH4
LH6
6 - 7