S29PL-J SPANSION [SPANSION], S29PL-J Datasheet - Page 52

• Manufacturer Part Number: S29PL-J
• Description: CMOS 3.0 Volt-only, Simultaneous-Read/Write Flash Memory with Enhanced VersatileIO Control
• Manufacturer: SPANSION [SPANSION]

13.5
13.6
50
Temporary Sector Unprotect
Secured Silicon Sector Flash Memory Region
This feature allows temporary unprotection of previously protected sectors to change data in-system. The
Sector Unprotect mode is activated by setting the RESET# pin to V
sectors can be programmed or erased by selecting the sector addresses. Once V
RESET# pin, all the previously protected sectors are protected again.
algorithm, and
device cannot enter the Temporary Sector Unprotection Mode.
Notes:
1. All protected sectors unprotected (If WP#/ACC = V
2. All previously protected sectors are protected once again
The Secured Silicon Sector feature provides a Flash memory region that enables permanent part
identification through an Electronic Serial Number (ESN) The 128-word Secured Silicon sector is divided into
64 factory-lockable words that can be programmed and locked by the customer. The Secured Silicon sector
is located at addresses 000000h-00007Fh in both Persistent Protection mode and Password Protection
mode. Indicator bits DQ6 and DQ7 are used to indicate the factory-locked and customer locked status of the
part.
The system accesses the Secured Silicon Sector through a command sequence (see the
Silicon Sector Command Sequence on page
Sector command sequence, it may read the Secured Silicon Sector by using the addresses normally
occupied by the boot sectors. This mode of operation continues until the system issues the Exit Secured
Silicon Sector command sequence, or until power is removed from the device. Once the Enter SecSi Sector
Command sequence has been entered, the standard array cannot be accessed until the Exit SecSi Sector
command has been entered or the device has been reset. On power-up, or following a hardware reset, the
device reverts to sending commands to the normal address space. Note that the ACC function and unlock
bypass modes are not available when the Secured Silicon Sector is enabled.
Figure 21.1 on page 81
D a t a
Figure 13.2 Temporary Sector Unprotect Operation
S h e e t
shows the timing diagrams, for this feature. While PPB lock is set, the
S29PL-J
IL
, upper two and lower two sectors will remain protected).
Unprotect Completed
( A d v a n c e
Program Operations
56). After the system has written the Enter Secured Silicon
Temporary Sector
Perform Erase or
RESET# = V
RESET# = V
(Note 1)
(Note 2)
START
ID
IH
I n f o r m a t i o n )
ID
. During this mode, formerly protected
Figure 13.2 on page 50
S29PL-J_00_A9 September 22, 2006
ID
is removed from the
Enter/Exit Secured
shows the