ARM ARM DUI 0224I - page 353

Memory Expansion Boards
ARM DUI 0224I Copyright © 2003-2010 ARM Limited. All rights reserved. E-3
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.
Expansion connector
SMAADD[25:0] and control signals
SMDATA[31:0]
CSWIDTH1
CSWIDTH0
SBSCL
SBSDA E2PROM
3V3
GND
CSWIDTH
select link
Static
memory
Chip
select
links
CS[7:4]
EXPnCS (CS3)