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Western Digital Hard Disk Drive OEM Specification
regards Password as Master Password.
Security Level
Zero indicates High level, one indicates Maximum level. If the host sets High level and the
password is forgotten, then the Master Password can be used to unlock the device. If the host
sets Maximum level and the user password is forgotten, only a Security Erase
Prepare/Security Unit command can unlock the device and all data will be lost.
Password
The text of the password
– all 32 bytes are always significant.
Master Password
Revision Code
The revision code field is returned in the IDENTIFY DEVICE word 92.
The valid revision codes are 0001h through FFFEh. The device accepts the command with a
value of 0000h or FFFFh in this field, but does not change Master Password Revision code.
The setting of the Identifier and Security level bits interact as follows.
Identifier=User / Security level = High
The password supplied with the command will be saved as the new user password. The security mode feature (lock
function) will be enabled from the next power on. The file may then be unlocked by either the user password or the
previously set master password.
Identifier=Master / Security level = High
This combination will set a master password but will NOT enable the security mode feature (lock function).
Identifier=User / Security level = Maximum
The password supplied with the command will be saved as the new user password. The security mode feature (lock
function) will be enabled from the next power on. The file may then be unlocked by only the user password. The
master password previously set is still stored in the file but may NOT be used to unlock the device.
Identifier=Master / Security level = Maximum
This combination will set a master password but will NOT enable the security mode feature (lock function).
