Memory Expansion Boards

 

 

 

 

 

 

 

0x00

 

 

 

EXPnCS

 

 

DYCS1

 

 

 

 

 

 

 

 

 

 

 

 

0x30

 

 

 

CS4

 

 

DYCS2

 

 

 

 

 

 

 

 

 

 

 

 

0x60

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CS5

 

 

DYCS3

0x90

 

 

 

 

 

 

 

 

 

 

CS6

 

 

Not used

 

 

 

 

 

 

 

 

 

 

 

 

0xC0

 

 

 

CS7

 

 

Not used

 

 

 

 

 

 

 

 

 

 

 

 

0xF0

 

 

 

Board string

 

 

Board string

 

 

 

 

 

 

 

 

and CRC

 

 

and CRC

0xFF

 

 

 

 

 

 

 

 

 

 

 

Static chip select

Dynamic chip select

 

 

 

information block

information block

 

 

 

Figure E-4 Chip select information block

 

The contents of a typical static memory expansion EEPROM with devices on EXPnCS

 

and CS4 is listed in Table E-3. Unused chip select blocks are filled with 0xFF.

 

Table E-3 Example contents of a static memory expansion EEPROM

 

 

 

 

 

 

 

 

 

 

 

 

Address

Contents

Contents

 

 

 

 

 

 

 

offset

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0x00

EXPnCS memory type

0x02 = Static NOR flash

 

 

 

 

 

 

 

 

 

 

0x01

EXPnCS memory width

0x12 - 16-bit device memory width, 32 bit chip select width

 

 

 

0x02

EXPnCS access time in 0.1ns (LSB)

0xb0 - LSB (of 1200 which 1200 * 0.1ns = 120ns access

 

 

time)

 

 

 

 

 

 

 

 

 

 

0x03

EXPnCS access time in 0.1ns (MSB)

0x04 - MSB (of 1200 which 1200 * 0.1ns = 120ns access

 

 

time)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0x04

EXPnCS memory size in bytes (LSB)

0x00

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0x05

EXPnCS memory size in bytes

0x00

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0x06

EXPnCS memory size in bytes

0x00

 

 

 

 

 

 

 

 

 

 

0x07

EXPnCS memory size in bytes (MSB)

0x04 (0x04000000 Bytes = 64MBytes)

 

 

 

 

 

 

 

 

 

 

 

 

E-8

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

ARM DUI 0224I

Page 358
Image 358
ARM ARM DUI 0224I manual Figure E-4 Chip select information block, Address Contents Offset