Advanced Power Management Feature Set (Apm) - Hitachi 7K80 - Deskstar - Hard Drive Specifications

10.13 Advanced Power Management feature set (APM)

This feature allows the host to select an advanced power management level. The advanced power management 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 advanced power management levels contain
discrete bands described in the section of SET FEATURES command in detail. This feature set uses the following
functions:
• A SET FEATURES subcommand to enable Advanced Power Management
• A SET FEATURES subcommand to disable Advanced Power Management
Advanced Power Management, Automatic Acoustic Management, and the Standby timer setting are independent
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 7K80 Hard Disk Drive Specification
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