S29GL128P SPANSION, S29GL128P Datasheet - Page 43

• Manufacturer Part Number: S29GL128P
• Description: Page Mode Flash Memory
• Manufacturer: SPANSION

November 21, 2006 S29GL-P_00_A3
5. There is no means to verify what the password is after it is set.
6. The Password Mode Lock Bit, once set, prevents reading the 64-bit password on the data bus and
7. The Password Mode Lock Bit is not erasable.
8. The lower two address bits (A1–A0) are valid during the Password Read, Password Program, and
9. The exact password must be entered in order for the unlocking function to occur.
10. The Password Unlock command cannot be issued any faster than 1 µs at a time to prevent a
11. Approximately 1 µs is required for unlocking the device after the valid 64-bit password is given to
12. Password verification is only allowed during the password programming operation.
13. All further commands to the password region are disabled and all operations are ignored.
14. If the password is lost after setting the Password Mode Lock Bit, there is no way to clear the PPB
15. Entry command sequence must be issued prior to any of any operation and it disables reads and
16. If the user attempts to program or erase a protected sector, the device ignores the command and
17. A program or erase command to a protected sector enables status polling and returns to read
18. The programming of the DYB, PPB, and PPB Lock for a given sector can be verified by writing
D a t a
further password programming.
Password Unlock.
hacker from running through all the 64-bit combinations in an attempt to correctly match a
password.
the device.
Lock Bit.
writes for Sector 0. Reads and writes for other sectors excluding Sector 0 are allowed.
returns to read mode.
mode without having modified the contents of the protected sector.
individual status read commands DYB Status, PPB Status, and PPB Lock Status to the device.
S h e e t
( A d v a n c e
S29GL-P MirrorBit
I n f o r m a t i o n )
TM
Flash Family
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