Sector Addressing Mode; Power Management Feature - Hitachi 7K320 - Travelstar Mobile Hard Drive Specifications

12.4 Sector Addressing Mode

All addressing of data sectors recorded on the device's media is by a logical sector address. The
logical CHS address for HTS7232XXL9SAXX / HTS7232XXL9A3XX is different from the actual
physical CHS location of the data sector on the disk media.
HTS7232XXL9SAXX / HTS7232XXL9A3XX support both Logical CHS Addressing Mode and LBA
Addressing Mode as the sector addressing mode.
The host system may select either the currently selected CHS translation addressing or LBA
addressing on a command-by-command basis by using the L bit in the DEVICE register. So a host
system must set the L bit to 1 if the host uses LBA Addressing mode.
Logical CHS Addressing Mode
12.4.1
The logical CHS addressing is made up of three fields: the cylinder number, the head number and
the sector number. Sectors are numbered from 1 to the maximum value allowed by the current CHS
translation mode but can not exceed 255(0FFh). Heads are numbered from 0 to the maximum value
allowed by the current CHS translation mode but can not exceed 15(0Fh). Cylinders are numbered
from 0 to the maximum value allowed by the current CHS translation mode but cannot exceed
65535(0FFFFh).
When the host selects a CHS translation mode using the INITIALIZE DEVICE PARAMETERS
command, the host requests the number of sectors per logical track and the number of heads per
logical cylinder. The device then computes the number of logical cylinders available in requested
mode.
The default CHS translation mode is described in the Identify Device Information. The current CHS
translation mode also is described in the Identify Device Information.
LBA Addressing Mode
12.4.2
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 is always true:
LBA = ( (cylinder * heads_per_cylinder + heads)
* 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 <--- LBA bits 27-24
LBA High <--- LBA bits 23-16
LBA Mid <--- LBA bits 15- 8
LBA Low <--- LBA bits 7- 0

12.5 Power Management Feature

The power management feature set permits a host to modify the behavior in a manner which
reduces the power required to operate. The power management feature set provides a set of
commands and a timer that enables a device to implement low power consumption modes.
HTS7232XXL9SAXX / HTS7232XXL9A3XX implement the following set of functions.
1. A Standby timer
2. Idle command
3. Idle Immediate command
4. Sleep command
5. Standby command
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7K320 SATA OEM Specification