AM29DL323GT90WMI AMD (ADVANCED MICRO DEVICES), AM29DL323GT90WMI Datasheet - Page 56

• Manufacturer Part Number: AM29DL323GT90WMI
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Specifications of AM29DL323GT90WMI

• Lead Free Status / Rohs Status: Not Compliant

56
Temporary Sector Unprotect
SecSi™ (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
grammed or erased by selecting the sector addresses. Once V
the RESET# pin, all the previously protected sectors are protected again. 2 shows
the algorithm, and 21 shows the timing diagrams, for this feature. While PPB lock
is set, the 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 SecSi (Secured Silicon) Sector feature provides a Flash memory region that
enables permanent part identification through an Electronic Serial Number (ESN)
The 128-word SecSi sector is divided into 64 factory-lockable words that can be
programmed and locked by the customer. The SecSi sector is located at ad-
dresses 000000h-00007Fh in both Persistent Protection mode and Password
Protection mode. It uses indicator bits (DQ6, DQ7) to indicate the factory-locked
and customer-locked status of the part.
The system accesses the SecSi Sector through a command sequence (see the
"Enter SecSi™ Sector/Exit SecSi Sector Command
system has written the Enter SecSi Sector command sequence, it may read the
SecSi Sector by using the addresses normally occupied by the boot sectors. This
mode of operation continues until the system issues the Exit SecSi Sector com-
mand sequence, or until power is removed from the device. On power-up, or
following a hardware reset, the device reverts to sending commands to the nor-
mal address space. Note that the ACC function and unlock bypass modes are not
available when the SecSi Sector is enabled.
Factory-Locked Area (64 words)
The factory-locked area of the SecSi Sector (000000h-00003Fh) is locked when
the part is shipped, whether or not the area was programmed at the factory. The
sectors will remain protected).
Figure 2. Temporary Sector Unprotect Operation
ID
. During this mode, formerly protected sectors can be pro-
S29PL127J/S29PL129J/S29PL064J/S29PL032J
Unprotect Completed
Program Operations
Temporary Sector
Perform Erase or
RESET# = V
RESET# = V
P R E L I M I N A R Y
(Note 1)
(Note 2)
START
ID
IH
Sequence" section). After the
IL
, upper two and lower two
ID
is removed from
31107A5 March 15, 2004