s29ns01gs Meet Spansion Inc., s29ns01gs Datasheet - Page 18

• Manufacturer Part Number: s29ns01gs
• Description: S29ns01gs 1024 Megabit 128 Megabyte 16-bit Data Width, Burst Access, Simultaneous Read/write, 1.8 Volt-only Flash Memory In 65 Nm Mirrorbit Technology
• Manufacturer: Meet Spansion Inc.

6.4
6.5
6.6
18
Secure Silicon Region ASO
SSR Lock ASO
Configuration Register ASO
Like the JEDEC Device ID information, CFI information is structured to work with any memory data bus width
e.g. x8, x16, x32. The code values are always byte wide but are located at data bus width address boundaries
such that incrementing the device address reads successive byte, word, or double word locations with the
codes always located in the least significant byte location of the data bus. Because the data bus is word wide
each code byte is located in the lower half of each word location and the high order byte is always zero.
For further information, please refer to the Spansion CFI Version 1.4 (or later) Specification (see also JEDEC
publications JEP137 and JESD68.01). Please contact JEDEC (http://www.jedec.org) for their standards and
the Spansion CFI Publications may be found at the Spansion Web site
(http://www.spansion.com/CFI_v1.4_VendorSpec_Ext_A0.pdf
The Secure Silicon Region (SSR) provides an extra Flash memory area that can be programmed once and
permanently protected from further changes i.e. it is a One Time Program (OTP) area. The SSR cannot be
erased. The SSR is 1Kbytes in length. It consists of 512 bytes for factory data and 512 bytes for customer-
secured data.
The SSR is overlaid in the sector address specified by the SSR enter command.
Page or Bit-field programming commands may be used to write data into the SSR. The Bit-field commands
allow for incremental programming of bits, bytes, or words in the customer portion until that section is locked.
However, when programming with these bit oriented programs a special format is used in which half of the
SSR customer page is reserved and may not be programmed. This is explained later in the Bit-field
programming command description.
The SSR Lock is a single word at offset zero in the ASO sector. The SSR Lock consists of two bits. The
Customer Secure Silicon Region Protection Bit is in location 0. The Factory Secure Silicon Region Protection
Bit is in location 1. The SSR Lock location may be read to determine the lock status of the Factory and
Customer portions of the SSR. All other bits in this location return “1” if read. The Customer SSR Protection
Bit may be programmed by the SSR Lock programming command to permanently lock the Customer portion
of the SSR.
If the Customer SSR Protection Bit is programmed to “0”, the Customer SSR is protected and can not be
programmed. If this bit is read as “0” the Customer SSR is locked. If this bit is read as “1,” the Customer SSR
is available for programming. Once the Customer SSR has been programmed, the SSR Lock bit 0 should be
programmed to “0.” to protect the Customer SSR from further programming.
Similarly the Factory Secure Silicon Region Protection Bit is set to “0” when protected. This area is always
programmed and protected at the Spansion factory.
The Configuration Register Enter command is only valid when written to a bank that is in Read mode. The
configuration register mode address map appears within, and replaces Flash Array data of, the selected
sector address range. The meaning of the configuration register bits is defined in the configuration register
operation description. In configuration register mode a write of 00F0h to any address will return the sector to
Read mode. Each word (separate configuration register) of the Configuration Register ASO must be
programmed by a separate programming operation i.e. a single word is loaded into the write buffer for each
programming operation on the Configuration Register ASO.
(SA) + 0000h to 01FFh
(SA) + 0200h to 03FFh
Byte Address Range
S29NS-S MirrorBit
D a t a
Table 6.4 Secure Silicon Region
S h e e t
®
Eclipse
™
Flash Family
Secure Silicon Region
( P r e l i m i n a r y )
Customer
Factory
at the time of this document’s publication).
S29NS-S_00_02 April 20, 2009
512 Bytes
512 Bytes
Size