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GD32F403xx User Manual
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Figure 1-1. The structure of the Cortex
®
-M4 processor
Nested
Vectored
Interrupt
Controller
(NVIC)
Cortex-M4 core
Floating Point
Unit(FPU)
Flash Patch
Breakpoint
(FPB)
Cortex-M4 processor
Memory
Protection
Unit(MPU)
Data
Watchpoint
And Trace
(DWT)
AHB
Access port
(AHB-AP)
Bus Matrix
Instrumentation
Trace Macrocell
(ITM)
Trace Port
Interface Unit
(TPIU)
Serial-Wire
Or JTAG
Debug Port
(SWDP or SWJ-
DP)
CoreSight
ROM table
Wake-up
Interrupt
Controller
(WIC)
Interrupts and
Power control
Trace Port
Interface
System
AHB-Lite
System
interface
DCode
AHB-Lite
Data
interface
ICode
AHB-Lite
Data
interface
Serial-Wire or
JTAG Debug
Interface
PPB APB
Debug system
interface
1.2.
System architecture
A 32-bit multilayer bus is implemented in the
GD32F403xx devices, which enables parallel
access paths between multiple masters and slaves in the system. The multilayer bus consists
of an AHB interconnect matrix, one AHB bus and two APB buses. The interconnection
relationship of the AHB interconnect matrix is sho
wn below. In the following table, “1” indicates
the corresponding master is able to access the corresponding slave through the AHB
interconnect matrix, while the blank means the corresponding master cannot access the
corresponding slave through the AHB interconnect matrix.
Table 1-1. The interconnection relationship of the AHB interconnect matrix
IBUS DBUS SBUS DMA0 DMA1
FMC-I
1
FMC-D
1
1
1
SRAM
1
1
1
1
1
EXMC
1
1
1
1
1
AHB
1
1
1