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Rev. 1.00
36 of 576
January 28, 2022
32-Bit Arm
®
Cortex
®
-M0+ MCU
HT32F54231/HT32F54241/HT32F54243/HT32F54253
3 System
Architecture
Flash Memory
Cortex
®
-M0+
Processor
System
NVIC
SRAM
Controller
PDMA
(Note)
6 Channels
DMA re
quest
Inter
rupt req
uest
Bus M
atrix
Flash Memory
Interface
AHB to APB
Bridge
I/O Port
GPIO
FMC
Control Registers
CKCU&RSTCU
Control Registers
PDMA
Control Registers
AHB
Peripherals
Divider
SRAM
APB IPs
Note: The PDMA is only available for the HT32F54243/HT32F54253 devices.
Figure 4. Bus Architecture
Memory Organization
The Arm
®
Cortex
®
-M0+ processor access and debug access share the single external interface to
external AHB peripherals. The processor access takes priority over debug access. The maximum
address range of the Cortex
®
-M0+ is 4 GB since it has 32-bit bus address width. Additionally,
a pre-defined memory map is provided by the Cortex
®
-M0+ processor to reduce the software
complexity of repeated implementation of different device vendors. However, some regions are
used by the Arm
®
Cortex
®
-M0+ system peripherals. Refer to the Arm
®
Cortex
®
-M0+ Technical
Reference Manual for more information. The following figure shows the memory map of the
HT32F54231/HT32F54241/HT32F54243/HT32F54253 series of devices, including Code, SRAM,
peripheral, and other pre-defined regions.