To Next Page

To Previous Page

Deskstar 7K250 Hard Disk Drive Specification

170

12.34 Security Unlock (F2h)

Table 103: Security Unlock command (F2h)

This command unlocks the password and causes the device to enter device unlock mode. If a power on reset or

hard reset is done without executing the Security Disable Password command after this command is completed, the

device will be in device lock mode. The password has not been changed yet.

The Security Unlock command requests the transfer of a single sector of data from the host including information

specified in the table below.

If the Identifier bit is set to master and the drive is in high security mode, the password supplied will be compared

with the stored master password. If the drive is in maximum security mode, the security unlock will be rejected.

If the Identifier bit is set to user, the drive compares the supplied password with the stored user password.

If the password compare fails, the device returns an abort error to the host and decrements the unlock attempt

counter. This counter is initially set to five and is decremented for each password mismatch. When this counter

reaches zero, all password protected commands are rejected until there is a hard reset or a power off.

Identifier

A zero indicates that the device regards Password as the User Password. A one indicates that the device regards

Password as the Master Password.

The user can detect if the attempt to unlock the device has failed due to a mismatched password since this is the

only reason that an abort error will be returned by the drive AFTER the password information has been sent to the

device. An abort error returned by the device BEFORE the password data has been sent to the drive indicates that

another problem exists.

Command Block Output Registers Command Block Input Registers

Data - - - - - - - - Data - - - - - - - -

Feature - - - - - - - - Error see below

Sector Count - - - - - - - - Sector Count - - - - - - - -

Sector Number - - - - - - - - Sector Number - - - - - - - -

Cylinder Low - - - - - - - - Cylinder Low - - - - - - - -

Cylinder High - - - - - - - - Cylinder High - - - - - - - -

Device/Head 1 - 1 D - - - - Device/Head - - - - - - - -

Command 1 1 1 1 0 0 1 1 Status see below

Error Register Status Register

7654321 0 76543 21 0

CRC UNC 0 IDN 0 ABT T0N AMN BSY RDY DF DSC DRQ COR IDX ERR

00000V0 0 0V0V- 0- V

Word Description

00 Control Word

bit 0 : Identifier (1- Master, 0- User)

bit 1-15 : Reserved

01-16 Password (32 bytes)

17-255 Reserved

Hitachi 7K250 - Deskstar - Hard Drive User Manual

Questions and Answers: