BootROM
RM0082
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Doc ID 018672 Rev 1
38.3 Hardware
overview
Figure 113. Hardware memory
38.3.1
eROM (Embedded ROM)
eROM is the 32KB of area starting from 0xFFFF_0000. The ARM processor is mapped to
HIGH vectors and starts executing instructions from 0xFFFF_0000.
38.3.2 Shadow
memory
Shadow memory is that area, where BootROM copies the X-Loader after reading/receiving
from any of the booting processes. Address where X-Loader is copied in the shadow
memory is specified in the X-Loader’s header.
38.3.3 System
controller
The system controller is used to program/control the system clock mode and frequency.
After reset, the system is set to DOZE mode.
BootROM configures System in different modes for different booting type:-
c)
For Serial NOR, Parallel NOR, 8/16 bit NAND and BootROM bypass booting:
SLOW mode (CPU 24 MHz - AHB 24 MHz)
d)
USB booting: NORMAL mode (CPU 333 MHz - AHB 166 MHz)
ARM
Shadow
Memory
eSRAM
FFFF0000h
eROM
High Vectors
SDRAM
(DDR2)
NAND/
NOR
FLASHES
Power On Reset
D2800000h
SPEAr300
RAS Area
50030000h
eRAM
Boot ROM