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SIOC 實驗 6 ： DMA

黃彥翔 /陳慶瀚MIAT實驗室

2

實驗目的 控制 DMA自動搬一記憶體或周邊之資料，並透過 VCP傳送到超級終端機顯示操作過程。

實作重點 DMA的控制

Polling Interrupt

SIOC DMA 簡介

DMA(Direct Memory Access)，無須 CPU可直接控制記憶體，透過 DMA，能使 CPU的效率大為提高。

最多有兩個 DMA控制器， DMA1 有 7 個通道，每個通道專門用來管理來自一個或多個外部的請求，還有一個仲裁器來協調各個 DMA請求的優先權。

3

WU-YANG Technology Co., Ltd.

DMA Registers

DMA Channel Mapping

5

DMA Request Mapping

6

DMA Interrupt Status Register

7

DMA Interrupt Status Register Cont.,

8

DMA Interrupt Flag Clear Register

9

DMA Channel x Configuration Register

10

DMA Channel x Configuration Register Cont.,

11

DMA Channel x Configuration Register Cont.,

12

DMA Channel x Number of Data Register

13

DMA Channel x Peripheral Address Register

14

DMA Channel x Memory Address Register

15

DMA Register Mapping

16

DMA Register Mapping Cont.,

17

DMA Register Mapping Cont.,

18

DMA Register Mapping Cont.,

19

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DMA Standard Driver Library

DMA Standard Driver Library List

21

DMA DeInit Function

22

DMA Init Function

23

DMA Init Function Cont.,

24

DMA Init Function Cont.,

25

DMA Init Function Cont.,

26

DMA Init Function Cont.,

27

DMA Init Function Cont.,

28

DMA Init Function Cont.,

29

DMA Command Function

30

DMA Interrupt Function

31

DMA Interrupt Function Cont.,

32

DMA Get CurrDataCounter Function

33

DMA Get Flag Status Function

34

DMA Get Flag Status Function Cont.,

35

DMA Get Flag Status Function Cont.,

36

DMA Get Flag Status Function Cont.,

37

DMA Get Flag Status Function Cont.,

38

DMA Clear Flag Function

39

DMA Get Interrupt Status Function

40

DMA Get Interrupt Status Function Cont.,

41

DMA Get Interrupt Status Function Cont.,

42

DMA Get Interrupt Status Function Cont.,

43

DMA Clear Interrupt Pending Bit Function

44

實驗 1 – Polling DMA

Goal Use DMA to copy data from memory to memory

Principle Check the DMA flag

45

Development Flow

46

Embedded Software Side Download Program to the Flash of the STM32

0

1

2

3

4

RCC Configure

NVIC Configure

DMA Configure

Check DMA Complete Flag

=1

=1

=1

=1

=1

RCC Configure

47

/* RCC Configure *//* DMA1 clock enable */ RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);

Turn On DMA1 Clock

DMA Configure

48

/* DMA Configure */void DMA_Configuration(void){ DMA_InitTypeDef DMA_InitStructure;

/* DMA1 channel6 configuration */ DMA_DeInit(DMA1_Channel6); DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)SRC_Const_Buffer; DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)DST_Buffer; DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; DMA_InitStructure.DMA_BufferSize = BufferSize; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Enable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word; DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; DMA_InitStructure.DMA_Priority = DMA_Priority_High; DMA_InitStructure.DMA_M2M = DMA_M2M_Enable; DMA_Init(DMA1_Channel6, &DMA_InitStructure);}

User Program

49

/* User Program */ while (DMA_GetFlagStatus(DMA1_FLAG_TC5) == RESET); DMA_ClearFlag(DMA1_FLAG_TC5); DMA_Configuration(); //DMA_Cmd(DMA1_Channel5, ENABLE);

實驗 2 – Interrupt DMA

Goal Use DMA to copy data from memory to memory

Principle Use the DMA Interrupt

50

Development Flow

51

Download Program to the Flash of the STM32F103C8

0

1

2

3

4

RCC Configure

NVIC Configure

DMA Configure

Check DMA Interrupt

=1

=1

=1

=1

=1

Q & A