AM29PDL128G70 SPANSION [SPANSION], AM29PDL128G70 Datasheet - Page 24

• Manufacturer Part Number: AM29PDL128G70
• Description: 128 Megabit (8 M x 16-Bit/4 M x 32-Bit) CMOS 3.0 Volt-only, Simultaneous Read/ Write Flash Memory with VersatileIO Control
• Manufacturer: SPANSION [SPANSION]

SECTOR PROTECTION
The Am29PDL128G features several levels of sector
protection, which can disable both the program and
erase operations in certain sectors or sector groups:
Persistent Sector Protection
A command sector protection method that replaces
the old 12 V controlled protection method.
Password Sector Protection
A highly sophisticated protection method that requires
a password before changes to certain sectors or sec-
tor groups are permitted
WP# Hardware Protection
A write protect pin that can prevent program or erase
operations in sectors 0, 1, 268, and 269.
All parts default to operate in the Persistent Sector
Protection mode. The customer must then choose if
the Persistent or Password Protection method is most
desirable. There are two one-time programmable
non-volatile bits that define which sector protection
method will be used. If the customer decides to con-
tinue using the Persistent Sector Protection method,
they must set the Persistent Sector Protection
Mode Locking Bit. This will permanently set the part
to operate only using Persistent Sector Protection. If
July 29, 2002
SGA66
SGA67
SGA68
SGA69
SGA70
SGA71
SGA72
SGA73
SGA74
SGA75
SGA76
SGA77
SGA78
SGA79
Sector
Group
A21
Table 8. Sector Block Addresses for Protection/Unprotection (Continued)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
A20
1
1
1
1
1
1
1
1
1
1
1
1
1
1
A19
1
1
1
1
1
1
1
1
1
1
1
1
1
1
A18
0
0
1
1
1
1
1
1
1
1
1
1
1
1
A17
P R E L I M I N A R Y
1
1
0
0
1
1
1
1
1
1
1
1
1
1
A16
Am29PDL128G
0
1
0
1
0
1
1
1
1
1
1
1
1
1
A15
X
X
X
X
X
0
0
1
1
1
1
1
1
1
1
1
the customer decides to use the password method,
they must set the Password Mode Locking Bit. This
will permanently set the part to operate only using
password sector protection.
It is important to remember that setting either the Per-
sistent Sector Protection Mode Locking Bit or the
Password Mode Locking Bit permanently selects
the protection mode. It is not possible to switch be-
tween the two methods once a locking bit has been
set. It is important that one mode is explicitly se-
lected when the device is first programmed, rather
than relying on the default mode alone. This is so
that it is not possible for a system program or virus to
later set the Password Mode Locking Bit, which would
cause an unexpected shift from the default Persistent
Sector Protection Mode into the Password Protection
Mode.
The WP# Hardware Protection feature is always avail-
able, independent of the software managed protection
method chosen.
The device is shipped with all sectors unprotected.
AMD offers the option of programming and protecting
sectors at the factory prior to shipping the device
through AMD’s ExpressFlash™ Service. Contact an
AMD representative for details.
A14
X
X
X
X
X
0
1
0
1
1
1
1
1
1
1
1
A13
X
X
X
X
X
X
0
0
0
0
1
1
1
1
A12
X
X
X
X
X
X
0
0
1
1
0
0
1
1
A11
X
X
X
X
X
X
0
1
0
1
0
1
0
1
SA239 to SA242
SA243 to SA246
SA247 to SA250
SA251 to SA254
SA255 to SA258
SA259 to SA261
Sectors
SA262
SA263
SA264
SA265
SA266
SA267
SA268
SA269
23