s71gs256nc0bawak0 Meet Spansion Inc., s71gs256nc0bawak0 Datasheet - Page 60

• Manufacturer Part Number: s71gs256nc0bawak0
• Description: Stacked Multi-chip Product Mcp 256/128 Megabit 16/8m X 16-bit Cmos 3.0 Volt Vcc And 1.8 V Vio Mirrorbit Tm Uniform Sector Page-mode Flash Memory With 64/32 Megabit 4/2m X 16-bit 1.8v Psram
• Manufacturer: Meet Spansion Inc.

60
The Secured Silicon sector address space in this device is allocated as follows:
The system accesses the Secured Silicon Sector through a command sequence
(see “Write Protect (WP# )”). After the system has written the Enter Secured Sil-
icon Sector command sequence, it may read the Secured Silicon Sector by using
the addresses normally occupied by the first sector (SA0). This mode of operation
continues until the system issues the Exit Secured Silicon Sector command se-
quence, or until power is removed from the device. On power-up, or following a
hardware reset, the device reverts to sending commands to sector SA0.
Customer Lockable: Secured Silicon Sector NOT Programmed or
Protected At the Factory
Unless otherwise specified, the device is shipped such that the customer may
program and protect the 256-byte Secured Silicon sector.
The system may program the Secured Silicon Sector using the write-buffer, ac-
celerated and/ or unlock bypass methods, in addition to t he standar d
programming command sequence. See “Command Definitions” .
Programming and protecting the Secured Silicon Sector must be used with cau-
tion since, once protected, there is no procedure available for unprotecting the
Secured Silicon Sector area and none of the bits in the Secured Silicon Sector
memory space can be modified in any way.
The Secured Silicon Sector area can be protected using one of the following
procedures:
T Write the three-cycle Enter Secured Silicon Sector Region command se-
T To verify the protect/unprotect status of the Secured Silicon Sector, follow the
Once the Secured Silicon Sector is programmed, locked and verified, the system
must write the Exit Secured Silicon Sector Region command sequence to return
to reading and writing within the remainder of the array.
Factory Locked: Secured Silicon Sector Programmed and
Protected At the Factory
I n devices with an ESN, the Secured Silicon Sector is protected when the device
is shipped from the factory. The Secured Silicon Sector cannot be modified in any
way. An ESN Factory Locked device has an 16-byte random ESN at addresses
000000h–000007h. Please contact your sales representative for details on order-
ing ESN Factory Locked devices.
Customers may opt to have their code programmed by the factory through the
ExpressFlash service (Express Flash Factory Locked). The devices are then
shipped from the factory with the Secured Silicon Sector permanently locked.
Contact your sales representative for details on using the ExpressFlash service.
quence, and then follow the in-system sector protect algorithm, except that
RESET# may be at either V
Secured Silicon Sector without raising any device pin to a high voltage. Note
that this method is only applicable to the Secured Silicon Sector.
algorithm.
Secured Silicon Sector
000000h–000007h
000008h–00007Fh
Address Range
S29GLxxxN MirrorBit
Determined by customer
Customer Lockable
A d v a n c e
IH
or V
ID
. This allows in-system protection of the
TM
ESN Factory Locked
Flash Family
I n f o r m a t i o n
Unavailable
ESN
Determined by customer
ESN or determined by
Factory Locked
ExpressFlash
customer
S29GLxxxN_MCP_A1 December 15, 2004