Hitachi hard disk drive specifications 
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9.14   SATA BIST (Built-in Self Test) 
The device supports the following BIST modes, and begins operations when it receives BIST Activate FIS. 
F – Far End Analog Loopback. 
L – Far End Retimed Loopback 
T – Far End Transmit only 
A – ALIGN Bypass (valid only in combination with T bit) 
S – Bypass Scrambling (valid only in combination with T bit) 
 
9.15   SATA Interface Power Management 
The  device  supports  both  receiving  host-initiated  interface  power  management  requests  and  initiating 
interface power management. The device initiates interface power management when the device enters its 
power saving mode whose power consumption is lower than Normal Idle mode. 
 
9.16   Software Setting Preservation 
When a device is enumerated, software will configure the device using SET FEATURES and other commands.   
These software settings are often preserved across software reset but not necessarily across hardware reset.   
In Parallel ATA, only commanded hardware resets can occur, thus legacy software only reprograms settings that 
are cleared for the particular type of reset it has issued.    In Serial ATA, COMRESET is equivalent to hard reset 
and a non-commanded COMRESET may occur if there is an asynchronous loss of signal.    Since COMRESET 
is equivalent to hardware reset, in the case of an asynchronous loss of signal some software settings may be 
lost without legacy software knowledge.    In order to avoid losing important software settings without legacy 
driver knowledge, the software settings preservation ensures that the value of important software settings is 
maintained across a COMRESET.    Software settings preservation may be enabled or disabled using SET 
FEATURES with a subcommand code of 06h.    If a device supports software settings preservation, the feature 
shall be enabled by default. 
9.16.1    COMRESET Preservation Requirements 
The software settings that shall be preserved across COMRESET are listed below.    The device is only required 
to preserve the indicated software setting if it supports the particular feature/command the setting is associated 
with. 
INITIALIZE  DEVICE  PARAMETERS:  Device  settings  established  with  the  INITIALIZE  DEVICE 
PARAMETERS command. 
Power Management Feature Set Standby Timer: The Standby timer used in the Power Management 
feature set. 
Read/Write Stream Error Log: The Read Stream Error Log and Write Stream Error Logs (accessed using 
READ LOG EXT and WRITE LOG EXT). 
Security mode state: The security mode state established by Security Mode feature set commands (refer 
to section 6.13 of the ATA/6 specification).    The device shall not transition to a different security mode state 
based  on  a  COMRESET.    For example, the device  shall  not  transition  from  the  SEC5: Unlocked  / not 
Frozen state to state SEC4: Security enabled / Locked when a COMRESET occurs, instead the device shall 
remain in the SEC5: Unlocked / not Frozen state. 
SECURITY  FREEZE  LOCK:  The  Frozen  mode  setting  established  by  the  SECURITY  FREEZE  LOCK 
command. 
SECURITY UNLOCK: The unlock counter that is decremented as part of a failed SECURITY UNLOCK 
command attempt.