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E-8 Copyright © 2003-2007 ARM Limited. All rights reserved. ARM DUI 0224F
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
.
Static chip select
information block
DYCS1
DYCS2
DYCS3
Not used
Board string
and CRC
Dynamic chip select
information block
0x00
0x30
0x60
0x90
0xF0
0xFF
EXPnCS
CS4
CS5
CS6
Board string
and CRC
0xC0
Not used
CS7
Table E-3 Example contents of a static memory expansion EEPROM
Address
offset
Contents Contents
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)