Hitachi Deskstar 7K250, Specifications

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Deskstar 7K250 Hard Disk Drive Specification
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10.15 Automatic Acoustic Management feature set (AAM)
This feature set allows the host to select an acoustic management level. The acoustic management level may range
from the lowest acoustic emanation setting of 01h to the maximum performance level of FEh. Device performance
and acoustic emanation may increase with increasing acoustic management levels. The acoustic management levels
may contain discrete bands. Automatic Acoustic Management levels 80h and higher do not permit the device to enter
Standby mode as a result of the Automatic Acoustic Management algorithm. The Automatic Acoustic Management
feature set uses the following functions:
1. A SET FEATURES subcommand to enable Automatic Acoustic Management
2. A SET FEATURES subcommand to disable Automatic Acoustic 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 9 indicates that Automatic Acoustic Management feature is
supported if set. Word 86, bit 9 indicates that Automatic Acoustic Management is enabled if set. Word 94, bits 7-0s
contains the current Automatic Acoustic Management level if Automatic Acoustic Management is enabled, and bits
8-15 contain the Vendor's recommended AAM level.