Hitachi HTS542525K9SA00 Specifications page 226

Security Level
Zero indicates High level. One indicates Maximum level. If the host sets High level and the password is forgotten,
the Master Password can be used to unlock the device. If the host sets Maximum level and the user password is for-
gotten, only a Security Erase Prepare/Security Unit command can unlock the device and all data will be lost.
Password
All 32 bytes of the text of the password are always significant.
Master Password Revision Code
The Revision Code field is set with Master password. If Identifier is User, the Revision Code is not set. The Revi-
sion Code field is returned in Identify Device word 92. The valid Revision Codes are 0000h to FFFDh. The Default
Master Password Revision Code is FFFEh. The code FFFFh is reserved.
Identifier and Security level bits
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 drive 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 drive may then be unlocked by only the user password. The
master password previously set is still stored in the drive 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).
Deskstar 7K160 Hard Disk Drive Specification
212