S29GL-M Datasheet, PDF (55/116 Pages) SPANSION – 256,128,64,32,Megabit 3.0 Volt-only Page Mode Flash Memory featuring 0.23 μm MirrorBit Process Technology

Data Sheet
Temporary Sector Group Unprotect
This feature allows temporary unprotection of previously protected sector groups to change data
in-system. The Sector Group Unprotect mode is activated by setting the RESET# pin to V_ID. Dur-
ing this mode, formerly protected sector groups can be programmed or erased by selecting the
sector group addresses. Once V_ID is removed from the RESET# pin, all the previously protected
sector groups are protected again. For this feature, Figure 1 shows the algorithm, and Figure 23
shows the timing diagrams.
START
RESET# = V_ID
(Note 1)
Perform Erase or
Program Operations
RESET# = V_IH
Temporary Sector
Group Unprotect Completed
(Note 2)
Notes:
1. All protected sector groups unprotected (If WP# = V_IL, the highest or lowest address sector
remains protected for uniform sector devices, the top or bottom two address sectors remains
protected for boot sector devices).
2. All previously protected sector groups are protected once again.
Figure 1. Temporary Sector Group Unprotect Operation
October 10, 2006 S29GL-M_00_B6
S29GL-M MirrorBit^TM Flash Family
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