STM32f4 串口DMA配置与使用（含代码）

//-----------------DMA1配置-------------------------------------

void uart2_init(int bps)      

{

                GPIO_InitTypeDef                                         GPIO_InitStructure;

                USART_InitTypeDef                                 USART_InitStructure;

                NVIC_InitTypeDef                                         NVIC_InitStructure;

                

                RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE); //修改

                RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2,ENABLE);//修改

         

                GPIO_PinAFConfig(GPIOA,GPIO_PinSource2,GPIO_AF_USART2); //GPIOA2¸修改

                GPIO_PinAFConfig(GPIOA,GPIO_PinSource3,GPIO_AF_USART2); //GPIOA3¸修改

                

                //USART2¶Ë¿ÚÅäÖÃ

                GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_3; //修改

                GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; //¸´Óù¦ÄÜ

                GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;        //ËÙ¶È50MHz

                GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //ÍÆÍ츴ÓÃÊä³ö

                GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; //ÉÏÀ­

                GPIO_Init(GPIOA,&GPIO_InitStructure); //修改

 

                //USART2³õʼ»¯ÉèÖÃ

                USART_InitStructure.USART_BaudRate =bps; //²¨ÌØÂÊÉèÖÃ

                USART_InitStructure.USART_WordLength = USART_WordLength_8b; //×Ö³¤Îª8λÊý¾Ý¸ñʽ

                USART_InitStructure.USART_StopBits = USART_StopBits_1; //Ò»¸öֹͣλ

                USART_InitStructure.USART_Parity = USART_Parity_No;//ÎÞÆæżУÑéλ

                USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_CTS; //ÎÞÓ²¼þÊý¾ÝÁ÷¿ØÖÆ

                USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;        //ÊÕ·¢Ä£Ê½

                USART_Init(USART2, &USART_InitStructure); //³õʼ»¯´®¿Ú2

                

                USART_Cmd(USART2, ENABLE); //修改

                USART_DMACmd(USART2,USART_DMAReq_Tx,ENABLE);

                USART_ClearFlag(USART2, USART_FLAG_TC);

                USART_ITConfig(USART2, USART_IT_RXNE, DISABLE); //修改

                

                //Usart2 NVIC ÅäÖÃ

                NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//ÉèÖÃϵͳÖжÏÓÅÏȼ¶·Ö×é0

                NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;//´®¿Ú1ÖжÏͨµÀ

                NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3;//ÇÀÕ¼ÓÅÏȼ¶3

                NVIC_InitStructure.NVIC_IRQChannelSubPriority =3;        //×ÓÓÅÏȼ¶3

                NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;        //IRQͨµÀʹÄÜ

                NVIC_Init(&NVIC_InitStructure);        //¸ù¾ÝÖ¸¶¨µÄ²ÎÊý³õʼ»¯VIC¼Ä´æÆ÷¡¢

}

void usart2_dma_Config(uint32_t * usart2_dma_buffer, int byteLen)

{ 

                DMA_InitTypeDef                  DMA_InitStructure;

        

                RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1,ENABLE); //修改 

                DMA_DeInit(DMA1_Stream6);

                while (DMA_GetCmdStatus(DMA1_Stream6) != DISABLE){} //µÈ´ýDMA¿ÉÅäÖà 

                

                /* ÅäÖÃ DMA Stream */

                DMA_InitStructure.DMA_Channel = DMA_Channel_4; //ͨµÀÑ¡Ôñ

                DMA_InitStructure.DMA_PeripheralBaseAddr =((u32)&USART2->DR); //DMAÍâÉèµØÖ·

                DMA_InitStructure.DMA_Memory0BaseAddr = (u32)usart2_dma_buffer; //DMA ´æ´¢Æ÷0µØÖ·

                DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral; //´æ´¢Æ÷µ½ÍâÉèģʽ

                DMA_InitStructure.DMA_BufferSize =byteLen; //Êý¾Ý´«ÊäÁ¿ 

                DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //ÍâÉè·ÇÔöÁ¿Ä£Ê½

                DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //´æ´¢Æ÷ÔöÁ¿Ä£Ê½

                DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; //ÍâÉèÊý¾Ý³¤¶È:8λ

                DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; //´æ´¢Æ÷Êý¾Ý³¤¶È:8λ

                DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; //ʹÓÃÆÕͨģʽ 

                DMA_InitStructure.DMA_Priority = DMA_Priority_Medium; //ÖеÈÓÅÏȼ¶

                DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;         

                DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;

                DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single; //´æ´¢Æ÷Í»·¢µ¥´Î´«Êä

                DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; //ÍâÉèÍ»·¢µ¥´Î´«Êä

                DMA_Init(DMA1_Stream6, &DMA_InitStructure); //修改

                DMA_Cmd(DMA1_Stream6, ENABLE);

} 

void usart2_dma_ConfigHalfWord(uint16_t * usart2_dma_buffer, int byteLen)

{ 

                DMA_InitTypeDef                    DMA_InitStructure;

        

                RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1,ENABLE); //修改

                DMA_DeInit(DMA1_Stream6);

                while (DMA_GetCmdStatus(DMA1_Stream6) != DISABLE){} //修改

                

                /* ÅäÖÃ DMA Stream */

                DMA_InitStructure.DMA_Channel = DMA_Channel_4; //ͨµÀÑ¡Ôñ

                DMA_InitStructure.DMA_PeripheralBaseAddr =((u32)&USART2->DR); //DMAÍâÉèµØÖ·

                DMA_InitStructure.DMA_Memory0BaseAddr = (u32        )usart2_dma_buffer; //DMA ´æ´¢Æ÷0µØÖ·

                DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral; //´æ´¢Æ÷µ½ÍâÉèģʽ

                DMA_InitStructure.DMA_BufferSize =byteLen; //Êý¾Ý´«ÊäÁ¿ 

                DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //ÍâÉè·ÇÔöÁ¿Ä£Ê½

                DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //´æ´¢Æ÷ÔöÁ¿Ä£Ê½

                DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; //ÍâÉèÊý¾Ý³¤¶È:8λ

                DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; //´æ´¢Æ÷Êý¾Ý³¤¶È:8λ

                DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; //ʹÓÃÆÕͨģʽ 

                DMA_InitStructure.DMA_Priority =DMA_Priority_Medium; //ÖеÈÓÅÏȼ¶

                DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;         

                DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;

                DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single; //´æ´¢Æ÷Í»·¢µ¥´Î´«Êä

                DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; //ÍâÉèÍ»·¢µ¥´Î´«Êä

                DMA_Init(DMA1_Stream6, &DMA_InitStructure); //修改

                DMA_Cmd(DMA1_Stream6, ENABLE);

} 

void usart2_dma_ConfigByte(uint8_t * usart2_dma_buffer, int byteLen)

{ 

                DMA_InitTypeDef  DMA_InitStructure;

        

                RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1,ENABLE); //修改

                DMA_DeInit(DMA1_Stream6);

                while (DMA_GetCmdStatus(DMA1_Stream6) != DISABLE){} //修改

                

                /* ÅäÖÃ DMA Stream */

                DMA_InitStructure.DMA_Channel = DMA_Channel_4; //ͨµÀÑ¡Ôñ

                DMA_InitStructure.DMA_PeripheralBaseAddr =((u32)&USART2->DR); //修改

                DMA_InitStructure.DMA_Memory0BaseAddr = (u32        )usart2_dma_buffer; //修改

                DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral; //´æ´¢Æ÷µ½ÍâÉèģʽ

                DMA_InitStructure.DMA_BufferSize =byteLen; //Êý¾Ý´«ÊäÁ¿ 

                DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //ÍâÉè·ÇÔöÁ¿Ä£Ê½

                DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //´æ´¢Æ÷ÔöÁ¿Ä£Ê½

                DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; //ÍâÉèÊý¾Ý³¤¶È:8λ

                DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; //´æ´¢Æ÷Êý¾Ý³¤¶È:8λ

                DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; //ʹÓÃÆÕͨģʽ 

                DMA_InitStructure.DMA_Priority =DMA_Priority_Medium; //ÖеÈÓÅÏȼ¶

                DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;         

                DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;

                DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single; //´æ´¢Æ÷Í»·¢µ¥´Î´«Êä

                DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; //ÍâÉèÍ»·¢µ¥´Î´«Êä

                DMA_Init(DMA1_Stream6, &DMA_InitStructure); //修改

                //DMA_SetCurrDataCounter(DMA1_Stream6, byteLen);

                DMA_Cmd(DMA1_Stream6, ENABLE);

#include "sys.h"

#include <stm32f4xx.h>

 

void uart2_init(int bps);

void usart2_dma_Config(uint32_t * usart2_dma_buffer, int byteLen);

void usart2_dma_ConfigHalfWord(uint16_t * usart2_dma_buffer, int byteLen);

void usart2_dma_ConfigByte(uint8_t * usart2_dma_buffer, int byteLen);

 

void TIM4_IRQHandler(void)

{

        int i=0;

        uint8_t frameBufCopy[1024];//缓冲区

        if(TIM_GetITStatus(TIM4,TIM_IT_Update)==SET) //中断

        {

 

                  frameBuf[pixleInd]=input;

                

                        pixleInd++;     //像素计数器  

                  if(pixleInd>=552)

                        {

                                 pixleInd=0;

                                 frameCount++;//帧计数器

                        }

                        if(frameCount>=100)

                        {

                                frameCount=0;

                                

                           memcpy(frameBufCopy,frameBuf,552);

               usart2_dma_ConfigByte(frameBufCopy,552);//串口发送

                        }

 

                

        }

        TIM_ClearITPendingBit(TIM4,TIM_IT_Update);  //

//}

 

}

extern uint8_t frameBuf[1024];  

extern u16 pixleInd;           

extern u16 frameCount;