Fujitsu MHA2021AT Product Manual page 127

Interface
(33) SECURITY UNLOCK (F2h)
This command cancels LOCKED MODE.
The host transfers the 512-byte data shown in Table 1.1 to the device. Operation
of the device varies as follows depending on whether the host specifies the master
password or user password.
When the master password is selected
When the security level in LOCKED MODE is high, the password is
compared with the master password already set. If the passwords are the
same, LOCKED MODE is canceled. Otherwise, the Aborted Command error
is returned. If the security level in LOCKED MODE is set to the highest
level, the Aborted Command error is always returned.
When the user password is selected
The password is compared with the user password already set. If the
passwords are the same, LOCKED MODE is canceled. Otherwise, the
Aborted Command error is returned.
If the password comparison fails, the device decrements the UNLOCK counter.
The UNLOCK counter initially has a value of five. When the value of the
UNLOCK counter reaches zero, this command or the SECURITY ERASE UNIT
command causes the Aborted Command error until the device is turned off and
then on, or until a hardware reset is executed. Issuing this command with
LOCKED MODE canceled (in UNLOCK MODE) has no affect on the UNLOCK
counter.
Issuing this command in FROZEN MODE returns the Aborted Command error.
1F7
1F6
1F5
1F4
1F3
1F2
1F1
5-66
At command issuance (I-O register contents)
(CM) 1 1
H
(DH)
H
(CH) xx
H
(CL) xx
H
(SN) xx
H
(SC) xx
H
(FR) xx
H
1 1 0 0
DV xx
0 1
C141-E042-01EN