标题: 日立7K1000C系列硬盘高级电源管理 APM 值与磁头缩回及待机时间的关系 [打印本页] 作者: wzqkele 时间: 2010-9-21 17:13 标题: 日立7K1000C系列硬盘高级电源管理 APM 值与磁头缩回及待机时间的关系 Advanced Power Management
When the value in the Feature register is 05h (=Enable Advanced Power Management), the Sector Count
Register specifies the Advanced Power Management level.
FFh --- Aborted
C0 – Feh --- The deepest Power Saving mode is Normal Idle mode
(the same as Disable Advanced Power Management)
80 – BFh --- The deepest Power Saving mode is Low power Idle mode
01 – 7Fh --- The deepest Power Saving mode is Low RPM standby mode
00h --- Aborted
The idle time to Low power idle mode and Low RPM standby mode vary according to the value in Sector
Count register as follows:
When Low power idle mode is the deepest Power Saving mode,
Y1=(x-80h) * 5+120 [sec] (120<= Y1<=435)
Y2=N/A(the device does not go to Low RPM standby mode)
When Low RPM standby mode is the deepest Power Saving mode and the value in Sector Count register
is between 40h and 7Fh,
120<=Y1<=435 [sec] (default: 120 [sec])
Y2=(x-40h) * 60 + 600[sec] (600<=Y2<=4380)
Hitachi hard disk drive specifications
194
When Low RPM standby mode is the deepest Power Saving mode and the value in Sector Count register is
between 01h and 3Fh,
120<=Y1<=435 [sec] (default: 120 [sec])
Y2=600 [sec]
where x is the value in Sector Count register, y1 is the idle time to Low Power Idle mode, and y2 is the idle
time to Low RPM standby mode.
If Low power idle mode has already been enabled (i.e., y1 has been set) before Low RPM standby mode is
enabled, y1 is preserved. If Low power idle mode is disabled (i.e., y1 has not been set yet), y1 becomes
120[sec] when Low RPM standby mode is enabled.
Hitachi hard disk drive specifications
195
Enabled Power Saving mode and idle time (y1 and y2) are preserved until Advanced Power Management is
disabled, the deepest Power Saving mode becomes Normal Idle mode, or new time is set. They are
initialized with a hard/soft reset unless Reverting to power on defaults is disabled and the device receives a
soft reset.
Low Power Idle mode
Additional electronics are powered off, and heads are unloaded on the ramp, however the spindle is still
rotated at the full speed.
Low RPM standby mode
The heads are unloaded on the ramp, and the spindle is rotated at the 60-65% of the full speed.
When Feature register is 85h (=Disable Advanced Power Management), the deepest Power Saving mode
becomes normal Idle.