Memory Expansion Boards

 

SMDATA[31:0]

 

 

SMAADD[25:0] and control signals

 

 

 

 

Static

 

EXPnCS (CS3)

memory

 

 

Chip

 

 

CS[7:4]

select

 

connector

links

 

 

 

3V3

 

 

Expansion

 

 

CSWIDTH1

 

 

 

 

 

 

CSWIDTH0

 

 

 

 

CSWIDTH

 

 

GND

select link

 

 

 

 

 

SBSCL

 

 

 

SBSDA

E2PROM

 

Figure E-2 Static memory board block diagram

E.1.1 Operation without expansion memory

You can operate the PB926EJ-S without a memory expansion board because it has 2MB of SSRAM, 128MB SDRAM, 64MB NOR flash, and 64MB NAND flash permanently fitted.

You can use the expansion boards, however, to prototype or develop memory devices that are not available on the PB926EJ-S.

E.1.2 Memory board configuration

The E2PROM on the memory board can be read from the PB926EJ-S to identify the type of memory on the board and how it is configured. This information can be used by the application or operating system to initialize the memory space.

ARM DUI 0224I

Copyright © 2003-2010 ARM Limited. All rights reserved.

E-3

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ARM ARM DUI 0224I manual Operation without expansion memory, Memory board configuration