s71ws256nc0bawa30 Meet Spansion Inc., s71ws256nc0bawa30 Datasheet - Page 62

• Manufacturer Part Number: s71ws256nc0bawa30
• Description: Stacked Multi-chip Product Mcp 256/512/128 Megabit 32m/16m/8m X 16 Bit Cmos 1.8 Volt-only Simultaneous Read/write, Burst-mode Flash Memory With 128/64megabit 8m/4m X 16-bit Psram.
• Manufacturer: Meet Spansion Inc.

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Notes
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10. The Password Unlock command cannot be issued any faster than 1 µs at a time to prevent
11. Approximately 1 µs is required for unlocking the device after the valid 64-bit password is
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
15. Entry command sequence must be issued prior to any of any operation and it disables reads
16. If the user attempts to program or erase a protected sector, the device ignores the com-
17. A program or erase command to a protected sector enables status polling and returns to
18. The programming of the DYB, PPB, and PPB Lock for a given sector can be verified by writing
There is no special addressing order required for programming the password. Once the
Password is written and verified, the Password Mode Locking Bit must be set in order to pre-
vent access.
The Password Program Command is only capable of programming “0”s. Programming a “1”
after a cell is programmed as a “0” results in a time-out with the cell as a “0”.
The password is all “1”s when shipped from the factory.
All 64-bit password combinations are valid as a password.
There is no means to verify what the password is after it is set.
The Password Mode Lock Bit, once set, prevents reading the 64-bit password on the data
bus and further password programming.
The Password Mode Lock Bit is not erasable.
The lower two address bits (A1–A0) are valid during the Password Read, Password Program,
and Password Unlock.
The exact password must be entered in order for the unlocking function to occur.
a hacker from running through all the 64-bit combinations in an attempt to correctly match
a password.
given to the device.
PPB Lock Bit.
and writes for Bank 0. Reads and writes for other banks excluding Bank 0 are allowed.
mand and returns to read mode.
read 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.
A d v a n c e
S71WS-Nx0 Based MCPs
I n f o r m a t i o n
S71WS-N_01_A4 September 15, 2005