Figure 101. Security Unlock Command (F2H) - IBM DJSA-210 - Travelstar 10 GB Hard Drive Specifications

13.25 Security Unlock (F2h)
Command Block Output Registers
Register
Data
Feature
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/Head
Command
Error Register
7 6 5
CRC UNC 0
0 V 0

Figure 101. 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 to transfer a single sector of data from the host including
information specified in Figure 101 on page 150.
If the Identifier bit is set to master and the file is in high security mode then the password supplied will be
compared with the stored master password. If the file is in maximum security mode then the security
unlock will be rejected.
If the Identifier bit is set to user, then the file compares the supplied password with the stored user
password.
If the password compare fails then the device returns an abort error to the host and decrements the
unlock attempt counter. This counter is initially set to 5 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.
7 6 5 4 3 2 1 0
– – – – – – – –
– – – – – – – –
– – – – – – – –
– – – – – – – –
– – – – – – – –
– – – – – – – –
1 – 1 D – – – –
1 1 1 1 0 0 1 0
4 3 2 1 0
IDN 0 ABT T0N AMN
0 0 V 0 0
Travelstar 32GH/30GT/20GN hard disk drive specifications
Command Block Input Registers
Register
Data
Error
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/Head
Status
Status Register
7 6 5 4
BSY RDY DF DSC
0 V 0 –
149
7 6 5 4 3 2 1 0
– – – – – – – –
see below
– – – – – – – –
– – – – – – – –
– – – – – – – –
– – – – – – – –
– – – – – – – –
see below
3 2 1 0
DRQ COR IDX ERR
– 0 – V