MX28F640C3T Macronix International, MX28F640C3T Datasheet - Page 18

• Manufacturer Part Number: MX28F640C3T
• Description: 64M-BIT [4M x16] CMOS SINGLE VOLTAGE 3V ONLY FLASH MEMORY
• Manufacturer: Macronix International

Table 5. Sector Locking State Transitions
4.9.5 Sector Locking while Erase Suspend
The sector lock status can be performed during an erase
suspend by using standard locking command sequences
to unlock, lock, or lock-down a sector.
In order to change sector locking during an erase opera-
tion, the write erase suspend command (B0H) is placed
first; then check the status register until it is shown that
the actual erase operation has been suspended. Subse-
quent writing the desired lock command sequence to a
sector and the lock status will be changed. When com-
pleting any desired lock, read or program operation, re-
sume the erase operation with the Erase Resume Com-
mand (D0H).
If a sector is locked or locked-down during the same
P/N:PM0900
WP
0
0
0
1
1
1
1
Q1
0
0
1
0
0
1
1
Current State
(X, Y, Z)=
Q0
0
1
1
0
1
0
1
Lock-Down Disabled
Lock-Down Disabled
Locked (Default)
Locked-Down
Unlocked
Unlocked
Locked
Name
Operation if
Erase/Prog.
Enable ?
Yes
Yes
Yes
No
No
No
No
18
sector is being placed in erase suspend, the locking sta-
tus bits will be changed immediately, but when the erase
is resumed, the erase operation will complete.
Locking operation cannot be performed during a program
suspend.
4.9.6 Status Register Error Checking
The operation of locking system for this device can be
used the term "state (X,Y,Z)" to specify locking status,
where X=value of WP, Y=bit Q1 of the sector lock status
register, and Z=bit Q0 of the sector lock status register.
Q0 indicates if a sector is locked (1) or unlocked (0). Q1
indicates if a sector has been locked-down(1) or not (0).
Unchanged
Unchanged
Unchanged
Unchanged
MX28F640C3T/B
Lock
(001)
(101)
(111)
Lock Command Input Result (Next State)
Unchanged
Unchanged
Unchanged
Unchanged
(X, Y, Z)=
Unlock
(000)
(100)
(110)
www.DataSheet4U.com
REV. 0.6, AUG. 20, 2003
Lock-Down
Unchanged
Unchanged
(011)
(011)
(111)
(111)
(111)