256Mb: 3V Embedded Parallel NOR Flash
Protection Operations
In extended memory block mode, ERASE, CHIP ERASE, ERASE SUSPEND, and ERASE
RESUME commands are not allowed. The extended memory block cannot be erased,
and each bit of the extended memory block can only be programmed once.
The extended memory block is protected from further modification by programming
lock register bit 0. Once invoked, this protection cannot be undone.
The device remains in extended memory block mode until the EXIT EXTENDED MEM-
ORY BLOCK (90/00h) command is issued, which returns the device to read mode, or
until power is removed from the device. After a power-up sequence or hardware reset,
the device will revert to reading memory blocks in the main array.
EXIT PROTECTION Command
The EXIT PROTECTION COMMAND SET (90/00h) command is used to exit the lock
register, password protection, nonvolatile protection, volatile protection, and nonvola-
tile protection bit lock bit command set modes and return the device to read mode.
PDF: 09005aef84bd3b68
m29w_256mb.pdf - Rev. C 7/13 EN
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