s71ws256nc0bawa30 Meet Spansion Inc., s71ws256nc0bawa30 Datasheet - Page 67

• Manufacturer Part Number: s71ws256nc0bawa30
• Description: Stacked Multi-chip Product Mcp 256/512/128 Megabit 32m/16m/8m X 16 Bit Cmos 1.8 Volt-only Simultaneous Read/write, Burst-mode Flash Memory With 128/64megabit 8m/4m X 16-bit Psram.
• Manufacturer: Meet Spansion Inc.

13 Secured Silicon Sector Flash Memory Region
13.1
September 15, 2005 S71WS-N_01_A4
Factory Secured SiliconSector
The Secured Silicon Sector provides an extra Flash memory region that enables permanent part
identification through an Electronic Serial Number (ESN). The Secured Silicon Sector is 256 words
in length that consists of 128 words for factory data and 128 words for customer-secured areas.
All Secured Silicon reads outside of the 256-word address range returns invalid data. The Factory
Indicator Bit, DQ7, (at Autoselect address 03h) is used to indicate whether or not the Factory Se-
cured Silicon Sector is locked when shipped from the factory. The Customer Indicator Bit (DQ6)
is used to indicate whether or not the Customer Secured Silicon Sector is locked when shipped
from the factory.
Please note the following general conditions:
The Factory Secured Silicon Sector is always protected when shipped from the factory and has
the Factory Indicator Bit (DQ7) permanently set to a “1”. This prevents cloning of a factory locked
part and ensures the security of the ESN and customer code once the product is shipped to the
field.
These devices are available pre programmed with one of the following:
Customers may opt to have their code programmed through the Spansion programming services.
Spansion programs the customer's code, with or without the random ESN. The devices are then
shipped from the Spansion factory with the Factory Secured Silicon Sector and Customer Secured
Silicon Sector permanently locked. Contact your local representative for details on using Spansion
programming services.
While Secured Silicon Sector access is enabled, simultaneous operations are allowed except
for Bank 0.
On power-up, or following a hardware reset, the device reverts to sending commands to the
normal address space.
Reads can be performed in the Asynchronous or Synchronous mode.
Burst mode reads within Secured Silicon Sector wrap from address FFh back to address 00h.
Reads outside of sector 0 return memory array data.
Continuous burst read past the maximum address is undefined.
Sector 0 is remapped from memory array to Secured Silicon Sector array.
Once the Secured Silicon Sector Entry Command is issued, the Secured Silicon Sector Exit
command must be issued to exit Secured Silicon Sector Mode.
The Secured Silicon Sector is not accessible when the device is executing an Embedded Pro-
gram or Embedded Erase algorithm.
A random, 8 Word secure ESN only within the Factory Secured Silicon Sector
Customer code within the Customer Secured Silicon Sector through the Spansion
ming service.
Both a random, secure ESN and customer code through the Spansion programming service.
Customer
Factory
Sector
A d v a n c e
I n f o r m a t i o n
Table 13.1
Sector Size
128 words
128 words
S71WS-Nx0 Based MCPs
Addresses
000080h-0000FFh
000000h-00007Fh
Address Range
TM
program-
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