NP8P128A13BSM60E Datasheet, PDF (32/92 Pages) Numonyx B.V – 128-Mbit Parallel Phase Change Memory

Numonyx® Omneo™ P8P Datasheet
10.1.7
Locking Operations During Erase Suspend
Block lock configurations can be performed during an erase suspend by using the
standard locking command sequences to unlock, lock, or lock-down a block. This is
useful when another block needs to be updated while an erase operation is suspended.
To change block locking during an erase operation, first write the Erase Suspend
command, then check the Status Register until it indicates that the erase operation has
suspended. Next write the desired lock command sequence to a block; the lock state
will be changed. After completing lock, read, or program operations, resume the erase
operation with the Erase Resume command (D0h).
If a block is locked or locked-down during a suspended erase of the same block, the
locking status bits will change immediately. But, when resumed, the erase operation
will complete. Locking operations cannot occur during write suspend. Appendix A,
“Write State Machine” on page 80 shows valid commands during erase suspend.
Nested lock or write commands during erase suspend can return ambiguous Status
Register results. 60h followed by 01h commands lock a block. A Configuration Setup
command (60h) followed by an invalid command produces a lock command Status
Register error (SR.4 and SR.5 = 1). If this error occurs during erase suspend, SR.4 and
SR.5 remain at 1 after the erase resumes. When erase completes, the previous locking
command error hides the Status Register’s erase errors. A similar situation occurs if a
write operation error is nested within an erase suspend.
Table 14: Block Locking State Transitions
Current State
WP#
LAT
1
0
0
0
0
0
1
0
1
1
0
1
0
1
1
1
1
LAT
0
Name
0 Unlocked
1 Locked (default) ⁽¹⁾
0 Virtual lock-down ⁽⁴⁾
1 Locked-Down
0 Unlocked
1 Locked
0 Lock-Down Disabled
1 Lock-Down Disabled
Erase/Write
Allowed?⁽¹⁾
Lock Command Input Result
(Next State) ⁽⁵⁾
UnLock Lock
Lock-
Down
WP#
Toggle
Result
(Next
State)
Yes
000
001
011
100
No
000
001
011
101
No
011
011
011
110
No
011
011
011
111
Yes
100
101
111
000
No
100
101
111
001
Yes
110
111
111
010
No
110
111
111
011
Locking
Status
Readout
D1 D0
0
0
0
1
1
1
1
1
0
0
0
1
1
0
1
1
Notes:
1.
Additional illegal states are shown but are not recommended for normal, non-erroneous operational modes.
2.
“Erase/Write Allowed?” shows whether a block’s current locking state allows erase or write.
3.
At power-up or device reset, blocks default to locked state [001] if WP# = 0, the recommended default.
4.
Blocks in “virtual lock-down” appear to be in locked-down state when WP#=V_IL. WP# = 1 changes [010] to unlocked state
[110].
5.
“This column shows results of writing the four locking commands or WP# toggle from the current locking state.
Datasheet
32
July 2010
316144-07