Table of Contents
Advertisement
9.13.3 Recovered read errors
When a read operation for a sector has failed once and then has recovered at the specific ERP step, this
sector of data is automatically reallocated. A media verification sequence may be run prior to the
reallocation according to the predefined conditions.
9.14 Power-Up In Standby feature set
The Power-Up In Standby feature set allows devices to be powered-up into the Standby power
management state to minimize inrush current at power-up and to allow the host to sequence the spin-up
of devices.
This feature set will be enabled/disabled via the SET FEATURES command or use of jumper. When en-
abled by a jumper, the feature set shall not be disabled via the SET FEATURES command. The enabling
of this feature set shall be persistent after power cycle.
A device needs a SET FEATURES subcommand to spin-up to active state when the device has powered
up into Standby. The device remains in Standby until the SET FEATURES subcommand is received.
If power-up into Standby is enabled when an IDENTIFY DEVICE is received while the device is in Standby
as a result of powering up into Standby, the device shall set word 0 bit 2 to one to indicate that the re-
sponse is incomplete, only words 0 and 2 are correctly reported.
The IDENTIFY DEVICE information indicates the states as follows:
! identify device information is complete or incomplete
! this feature set is implemented
! this feature set is enabled or disabled
! the device needs the Set Features command to spin-up into active state
9.15 Advanced Power Management feature set (APM)
This feature allows the host to select an advanced power management level. The advanced power man-
agement level is a scale from the lowest power consumption setting of 01h to the maximum performance
level of FEh. Device performance may increase with increasing advanced power management levels.
Device power consumption may increase with increasing advanced power management levels. The ad-
vanced power management levels contain discrete bands described in the section of SET FEATURES
command in detail. This feature set uses the following functions:
1. A SET FEATURES subcommand to enable Advanced Power Management
2. A SET FEATURES subcommand to disable Advanced Power Management
Advanced Power Management, Automatic Acoustic Management, and the Standby timer setting are inde-
pendent functions. The device shall enter Standby mode if any of the following are true:
1. The Standby timer has been set and times out
2. Automatic Power Management is enabled and the associated algorithm indicates that the Standby
mode should be entered to save power
3. Automatic Acoustic Management is enabled and the associated algorithm indicates that the
Standby mode should be entered to reduce acoustical emanations
The IDENTIFY DEVICE response word 83, bit 3 indicates that Advanced Power Management feature is
supported if set. Word 86, bit 3 indicates that Advanced Power Management is enabled if set. Word 91,
bits 7-0 contains the current Advanced Power Management level if it is enabled.
Deskstar 120GXP hard disk drive specifications
92
Hide quick links:
Advertisement
Table of Contents
