96
Western Digital Hard Disk Drive OEM Specification
B)
30h; or
C)
10h;
g)
READ LOG DMA EXT command requesting one of the following log addresses:
A)
E0h;
B)
30h; or
C)
10h;
h)
SMART RETURN STATUS command; or
i)
SET FEATURES PUIS feature set device spin-up subcommand.
If a sanitize operation is interrupted by a power-on reset, the sanitize operation continues. If the device processes a
power-on reset and enters the PM5: PUIS and spin-up subcommand not supported state (see
), then the
device resumes processing the sanitize operation after receiving a media acc ess command. (The media access
command reports failure because the sanitize operation does not allow media access commands. However, since
the device has received a media access command, the device is spin-up.)
The SANITIZE STATUS EXT command returns information about the current sanitize operation, if any, including a
percentage of completion if a sanitize operation is in progress.
A CRYPTO SCRAMBLE EXT command, or OVERWRITE EXT command that returns command completion with no
error transitions the device into the SD2: Sanitize Operation state. The device remains in this state until the device
has completed the sanitize operation (see figure 9).
The SANITIZE FREEZE LOCK EXT command causes the device to transition to the SD1: Sanitize Frozen state and
causes any subsequent CRYPTO SCRAMBLE EXT command or OVERWRITE EXT command to be aborted. If the
device processes a power-on reset or a hardware reset, then the device transitions from the Sanitize Frozen state to
the Sanitize Idle state.
The crypto scramble operation makes previously written contents in the user data area irretrievable.
The overw
rite operation fills all user data w ith a four byte pattern passed w ithin the LBA field of the command. Parameters fo
r
the OVERWRITE EXT command include a count for multiple overwrites and the option to invert the four byte pattern
between consecutive overwrite passes.
A software reset does not cause the SD2: Sanitize Operation state to transition to another state.
9.20.2
Sanitize Device Feature
The Sanitize Device Feature Set is a powerful data erase feature. Two data erase features are supported. One is an
Overwrite Ext command, and the other is Crypto Scramble Ext command. The Crypto Scramble Ext command is
only available on data encryption models.
Individual Sanitize Device commands are identified by the value specified in the FEATURE field.
The following commands are supported for this feature.
Command
COMMAND field value
FEATURE field value
SANITIZE STATUS EXT
(‘B4’h)
(‘0000’h)
CRYPTO SCRAMBLE EXT
(‘B4’h)
(‘0011’h)
OVERWRITE EXT
(‘B4’h)
(‘0014’h)
SANITIZE FREEZE LOCK EXT
(‘B4’h)
(‘0020’h)
