Figure 112. Security Set Password Information - IBM IC25N040ATCS04 - Travelstar 40 GB Hard Drive Specifications

Word
00
01-16
17-18
19-255

Figure 112. Security Set Password information

Identifier
Security Level
Password
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 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).
Description
Control Word
bit 0 : Identifier (1-Master, 0-User)
bit 1-7 : Reserved
bit 8 : Security level (1-Maximum, 0-High)
bit 9-15 : Reserved
Password ( 32 bytes )
Master Password Revision Code (valid if
Word 0 bit 0 = 1)
Reserved
Zero indicates that the device should check the supplied password against the
user password stored internally. One indicates that the device should check the
given password against the master password stored internally.
A zero indicates a High level, a one indicates a Maximum level. If the host sets
the High level and the password is forgotten then the Master Password can be
used to unlock the device. If the host sets the Maximum level and the user pass-
word is forgotten, only a Security Erase Prepare/Security Unit command can
unlock the device and all data will be lost.
The 32 bytes are always significant in the text of the password.
The Revision Code field is set with Master password. If Identifier is User, the
Revision Code is not set. The Revision 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.
Travelstar 60GH & 40GN hard disk drive specifications
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