s29ns01gs Meet Spansion Inc., s29ns01gs Datasheet - Page 14

• 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.

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Address Space Maps
There are five address spaces within each device:
The main Flash Memory Array is the primary and default address space but, it may be partially overlaid by the
other four address spaces with one alternate address space available at any one time. The location where the
alternate address space is overlaid is defined by the address provided in the command that enables each
overlay. The portion of the command address that is sufficient to select a sector is used to select the sector
that is overlaid by an alternate Address Space Overlay (ASO).
Any address range, within the overlaid sector, not defined by an overlay address map, is reserved for future
use. All read accesses outside of an ASO address map within the selected sector, return non-valid data. The
locations will display actively driven data but the meaning of whatever ones or zeros appear are not defined.
There are three operation modes for each bank that determine what portions of the address space are
readable at any given time:
Each bank of the device can be in any operation mode but, only one bank can be in EA or ASO mode at any
one time.
In Read Mode a Flash Memory Array bank may be directly read by asynchronous or synchronous accesses
from the host system bus. The Control Unit (CU) puts all banks in Read mode during Power-on, a Hardware
Reset, after a Command Reset, or after a bank is returned to Read mode from EA mode. A bank with a
suspended EA is considered to be returned to Read mode even though some or all of the data in the bank
may be in an invalid state and thus not useful if read.
In EA mode the Flash memory array data in a bank is stable but undefined, and effectively unavailable for
read access from the host system. While in EA mode the bank is used by the CU in the execution of
commands. Typical EA mode operations are programming or erasing of data in the Flash array. All other
banks are available for read access while the one bank is in EA mode. This ability to read from one bank
while another bank is used in the execution of a command is called Simultaneous Read and Write (SRW) and
allows for continued operation of the system via the reading of data or execution of code from other banks
while one bank is programming or erasing data as a relatively long time frame background task.
In ASO mode, one of the overlay address spaces are overlaid in a bank (entered). That bank is in ASO mode
and no other bank may be in EA or ASO mode. All EA activity must be completed before entering any ASO
mode. A command for entering an EA or ASO mode while another bank is in EA or ASO mode will be
ignored.
After issuing one of the ASO enter commands there is a delay required before the ASO is readable. The
delay is generally less than 200 ns. It is recommended to issue a Status Read command to check the busy or
ready state of the memory before reading from the ASO. This will take sufficient time as to ensure that the
ASO data is available for read.
While an ASO mode is active (entered) in a bank, a read for Flash array data to any other bank is allowed.
ASO mode selects a specific sector for the overlaid address space. Other sectors in the ASO bank still
provide Flash array data and may be read during ASO mode. An ASO may overlay any sector in any bank.
While SSR Lock, SSR, or Configuration Register is overlaid only the SSR Lock, SSR, or Configuration
Register respectively may be programmed in the overlaid sector.
A Non-Volatile Flash Memory Array used for storage of data that may be randomly accessed by
asynchronous or synchronous read operations.
A Read Only Memory Array used for factory programmed permanent device characteristics information.
This area contains the Device Identification (ID) and Common Flash Interface (CFI) information.
A One Time Programmable (OTP) Non-volatile Flash array used for factory programmed permanent data,
and customer programmable permanent data. This is called the Secure Silicon Region (SSR).
An OTP location used to permanently protect the SSR. This is call the SSR Lock.
A volatile register set used to configure device behavior options. This is called the Configuration Register
set.
Read Mode
Embedded Algorithm (EA) Mode
Address Space Overlay (ASO) Mode
S29NS-S MirrorBit
D a t a
S h e e t
®
Eclipse
™
Flash Family
( P r e l i m i n a r y )
S29NS-S_00_02 April 20, 2009