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2.3
Memory Mapping
The memory mapping address is totally 4GB address. The assigned addresses
include the core (including core peripherals), on-chip Flash (including main
memory area, system memory area and option bytes), on-chip SRAM, and bus
peripherals (including AHB and APB peripherals). Please refer to the data
manual of the corresponding model for specific information of various addresses.
Embedded SRAM
Built-in static SRAM. It can access by byte, half word (16 bits) or full word (32
bits). The start address of SRAM is 0x2000 0000.
2.4
Startup Configuration
APM32F MCU series realizes a special mechanism. By configuring the BOOT
pin parameter and the nBOOT1 bit in FMC_OBCS, there are three different
startup modes, namely, the system can not only start from Flash memory or
system memory, but also start from the built-in SRAM. The memory selected as
the start zone is determined by the selected startup mode.
Table 6 Startup Mode Configuration and Access Mode
Startup mode
selection pin
Startup
mode
Access mode
BOOT1
BOOT0
X
0
Main flash
memory
（
Flash
）
The main flash memory is mapped to the boot space, but it can
still be accessed at its original address, that is, the contents of
the flash memory can be accessed in two address areas.
0
1
System
memory
The system memory is mapped to the boot space (0x0000
0000), but it can still be accessed at its original address.
1
1
Built-in
SRAM
SRAM can be accessed only at the starting address.
Note:
（
1
）
The boot space address is 0x0000 0000
（
2
）
The original address of Flash is 0x0800 0000
（
3
）
The original address of the system memory is 0x1FFF EC00
（
4
）
The starting address of SRAM is 0x2000 0000
（
5
）
The value of BOOT1 is negation of nBOOT1 option bit
The user can select the startup mode after reset by setting the states of BOOT1 (configuration nBOOT1)
and BOOT0 pins.
BOOT pin should keep the user's required startup configuration in standby mode. When exiting from the
standby mode, the value of boot pin will be latched.
If you choose to start from built-in SRAM, you must use NVIC's exception table and offset register to
remap the vector table to SRAM when writing the application code.
Embedded startup program
The embedded startup program is written on the production line by APEX and
stored in the system memory area.
