Lpc2131/2132/2134/2136/2138 Memory Re-Mapping And Boot Block - Philips LPC213 Series User Manual

Philips Semiconductors
Volume 1

2.2 LPC2131/2132/2134/2136/2138 memory re-mapping and boot block

2.2.1 Memory map concepts and operating modes
The basic concept on the LPC2131/2/4/6/8 is that each memory area has a "natural"
location in the memory map. This is the address range for which code residing in that area
is written. The bulk of each memory space remains permanently fixed in the same
location, eliminating the need to have portions of the code designed to run in different
address ranges.
Because of the location of the interrupt vectors on the ARM7 processor (at addresses
0x0000 0000 through 0x0000 001C, as shown in
Boot Block and SRAM spaces need to be re-mapped in order to allow alternative uses of
interrupts in the different operating modes described in
interrupts is accomplished via the Memory Mapping Control feature
mapping control" on page
Table 2:
Address
0x0000 0000
0x0000 0004
0x0000 0008
0x0000 000C
0x0000 0010
0x0000 0014
0x0000 0018
0x0000 001C
Table 3:
Mode
Boot
Loader
mode
User
Flash
mode
User RAM
mode
User manual
25).
ARM exception vector locations
Exception
Reset
Undefined Instruction
Software Interrupt
Prefetch Abort (instruction fetch memory fault)
Data Abort (data access memory fault)
Reserved
Note: Identified as reserved in ARM documentation, this location is used
by the Boot Loader as the Valid User Program key. This is descibed in
detail in "Flash Memory System and Programming" chapter on page 216.
IRQ
FIQ
LPC2131/2/4/6/8 memory mapping modes
Activation Usage
Hardware The Boot Loader always executes after any reset. The Boot Block
activation by interrupt vectors are mapped to the bottom of memory to allow
any Reset handling exceptions and using interrupts during the Boot Loading
process.
Software Activated by Boot Loader when a valid User Program Signature is
activation by recognized in memory and Boot Loader operation is not forced.
Boot code Interrupt vectors are not re-mapped and are found in the bottom of the
Flash memory.
Software Activated by a User Program as desired. Interrupt vectors are
activation by re-mapped to the bottom of the Static RAM.
User program
Rev. 01 — 24 June 2005
UM10120
Chapter 2: Memory map
Table 2 below), a small portion of the
Table 3. Re-mapping of the
(Section 3.6 "Memory
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
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