256Mb and 512Mb (256Mb/256Mb), P30-65nm
Security Modes
Block Lock Status
The Read Device Identifier command is used to determine a block’s lock status. Data
bits DQ[1:0] display the addressed block’s lock status; DQ0 is the addressed block’s lock
bit, while DQ1 is the addressed block’s lock-down bit.
Figure 12: Block Locking State Diagram
(Power-up/
Reset default)
[000]
D0h
01h
[001]
2Fh
Program/Erase Allowed
WP# = VIL = 0
Program/Erase Prevented
WP# = VIL = 0
2Fh
WP# toggle
D0h, 01h, or 2Fh
[010]
[011] (Locked-down)
(Virtual lock-down)
WP# toggle
(Lock-down
disabled,
WP# = VIH)
D0h
D0h
[110]
[100]
01h/2Fh
[111]
Program/Erase Allowed
WP# = VIH = 1
Program/Erase Prevented
WP# = VIH = 1
2Fh
01h
2Fh
(Power-up/
Reset default)
[101]
1. D0h = UNLOCK command; 01h = LOCK command; 60h (not shown) LOCK SETUP com-
mand; 2Fh = LOCK-DOWN command.
Note:
Block Locking During Suspend
Block lock and unlock changes can be performed during an erase suspend. To change
block locking during an erase operation, first issue the Erase Suspend command. Moni-
tor the Status Register until SR.7 and SR.6 are set, indicating the device is suspended
and ready to accept another command.
Next, write the desired lock command sequence to a block, which changes the lock
state of that block. After completing block lock or unlock operations, resume the erase
operation using the Erase Resume command.
Note:
A Lock Block Setup command followed by any command other than Lock Block, Unlock
Block, or Lock-Down Block produces a command sequence error and set Status Register
bits SR.4 and SR.5. If a command sequence error occurs during an erase suspend, SR.4
and SR.5 remains set, even after the erase operation is resumed. Unless the Status Reg-
ister is cleared using the Clear Status Register command before resuming the erase op-
eration, possible erase errors may be masked by the command sequence error.
If a block is locked or locked-down during an erase suspend of the same block, the lock
status bits change immediately. However, the erase operation completes when it is re-
sumed. Block lock operations cannot occur during a program suspend.
PDF: 09005aef84566799
p30_65nm_MLC_256Mb-512mb.pdf - Rev. A 1/13 EN
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