M29DW641F70N1 NUMONYX [Numonyx B.V], M29DW641F70N1 Datasheet - Page 71

• Manufacturer Part Number: M29DW641F70N1
• Description: 64 Mbit (4Mb x16, Multiple Bank, Page, Boot Block) 3V Supply Flash Memory
• Manufacturer: NUMONYX [Numonyx B.V]

M29DW641F
Appendix C
C.1
The M29DW641F has an extra block, the Extended Block, that can be accessed using a
dedicated command.
This Extended Block is 128 Words. It is used as a security block (to provide a permanent
security identification number) or to store additional information.
The Extended Block is divided into two memory areas of 64 Words each:
●
●
Bits DQ6 and DQ7 are the most significant bits in the Extended Block Protection indicator
and a specific procedure must be followed to read it. See
Block Protection indicator
The Extended Block can only be accessed when the device is in Extended Block mode. For
details of how the Extended Block mode is entered and exited, refer to the
Program command
Block Protection commands
Factory Locked section of the Extended Block
The first section of The Extended Block is permanently protected from Program Operations
and cannot be unprotected. The Random Number, Electronic Serial Number (ESN) and
Security Identification Number (see
in this section in the factory.
The first one is Factory Locked.
The second one is Customer Lockable. It is up to the customer to protect it from
Program Operations. Its status is indicated by bit DQ6 and DQ7. When DQ7 is set to ‘1’
and DQ6 to ‘0’, it indicates that this second memory area is Customer Lockable. When
DQ7 and DQ6 are both set to ‘1’, it indicates that the second part of the Extended Block
is Customer Locked and protected from Program Operations. Bit DQ7 being
permanently locked to either ‘1’ or ‘0’ is another security feature which ensures that a
customer lockable device cannot be used instead of a factory locked one.
Extended Memory Block
and
Section 6.3.2: Exit Extended Block command
” in
.
Table 5: Block Protection
Table 35: Extended Block Address and Data
, for details of how to read bit DQ7.
Section 3.6.2: Verify Extended
Extended Memory Block
, and to
Section 6.1.10:
Table 10:
) are written
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