LPC2925 NXP Semiconductors, LPC2925 Datasheet - Page 18

• Manufacturer Part Number: LPC2925
• Description: (LPC2921 - LPC2925) ARM9 microcontroller
• Manufacturer: NXP Semiconductors

NXP Semiconductors
LPC2921_2923_2925_0
Preliminary data sheet
www.DataSheet4U.com
6.8.2 Flash layout
Table 9.
The ARM processor can program the flash for ISP (In-System Programming) through the
flash memory controller. Note that the flash always has to be programmed by ‘flash words’
of 128 bits (four 32-bit AHB bus words, hence 16 bytes).
The flash memory is organized into eight ‘small’ sectors of 8 kB each and up to 11 ‘large’
sectors of 64 kB each. The number of large sectors depends on the device type. A sector
must be erased before data can be written to it. The flash memory also has sector-wise
protection. Writing occurs per page which consists of 4096 bits (32 flash words). A small
sector contains 16 pages; a large sector contains 128 pages.
Table 10
Table 10.
Synchronous timing
No buffer line
Single buffer line
Asynchronous timing
No buffer line
Single buffer line
Dual buffer line, single
speculative
Dual buffer line, always
speculative
Flash memory
sector number
11
12
13
14
15
16
17
18
0
1
2
3
4
5
6
gives an overview of the flash-sector base addresses.
Flash read modes
Flash sector overview
Sector size (kB)
8
8
8
8
8
8
8
8
64
64
64
64
64
64
64
Rev. 00.01 — 24 October 2008
for single (non-linear) reads; one flash-word read per word read
default mode of operation; most recently read flash word is kept until
another flash word is required
one flash-word read per word read
most recently read flash word is kept until another flash word is
required
on a buffer miss a flash read is done, followed by at most one
speculative read; optimized for execution of code with small loops
(less than eight words) from flash
most recently used flash word is copied into second buffer line; next
flash-word read is started; highest performance for linear reads
Flash memory
address
2000 0000h
2000 2000h
2000 4000h
2000 6000h
2000 8000h
2000 A000h
2000 C000h
2000 E000h
2001 0000h
2002 0000h
2003 0000h
2004 0000h
2005 0000h
2006 0000h
2007 0000h
ARM9 microcontroller with CAN and LIN
LPC2921/2923/2925
LPC2921
yes
yes
yes
yes
yes
yes
yes
yes
yes
no
no
no
no
no
no
LPC2923 LPC2925
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
no
no
no
no
© NXP B.V. 2008. All rights reserved.
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
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