Lba Addressing Mode - IBM IC25N040ATCS04 - Travelstar 40 GB Hard Drive Specifications

11.5.2 LBA addressing mode

Logical sectors on the device shall be linearly mapped with the first LBA addressed sector (sector 0) being
the same sector as the first logical CHS addressed sector ( cylinder 0, head 0, sector 1). Irrespective of
the logical CHS translation mode currently in effect, the LBA address of a given logical sector does not
change. The following formula is always true:
LBA = ((cylinder x heads_per_cylinder + heads) x sectors_per_track) +
sector - 1
where heads_per_cylinder and sectors_per_track are the current translation mode values.
On LBA addressing mode, the LBA value is set to the following register:
Device/Head
Cylinder High
Cylinder Low
Sector Number
<- - - LBA bits 27–24
<- - - LBA bits 23–16
<- - - LBA bits 15–8
<- - - LBA bits 7–0
Travelstar 60GH & 40GN hard disk drive specifications
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