bsp_usart_dma.h

#ifndef __USART_DMA_H

#define __USART_DMA_H

#include "stm32f4xx.h"

#include

//USART

#define DEBUG_USART                       USART1

#define DEBUG_USART_CLK                   RCC_APB2Periph_USART1

#define DEBUG_USART_RX_GPIO_PORT          GPIOA

#define DEBUG_USART_RX_GPIO_CLK           RCC_AHB1Periph_GPIOA

#define DEBUG_USART_RX_PIN                GPIO_Pin_10

#define DEBUG_USART_RX_AF                 GPIO_AF_USART1

#define DEBUG_USART_RX_SOURCE             GPIO_PinSource10

#define DEBUG_USART_TX_GPIO_PORT          GPIOA

#define DEBUG_USART_TX_GPIO_CLK           RCC_AHB1Periph_GPIOA

#define DEBUG_USART_TX_PIN                GPIO_Pin_9

#define DEBUG_USART_TX_AF                 GPIO_AF_USART1

#define DEBUG_USART_TX_SOURCE             GPIO_PinSource9

#define DEBUG_USART_BAUDRATE              115200

//DMA

#define DEBUG_USART_DR_BASE               (USART1_BASE+0x04)        

#define SENDBUFF_SIZE                     5000              //發(fā)送的數(shù)據(jù)量

#define DEBUG_USART_DMA_CLK               RCC_AHB1Periph_DMA2   

#define DEBUG_USART_DMA_CHANNEL           DMA_Channel_4

#define DEBUG_USART_DMA_STREAM            DMA2_Stream7

void Debug_USART_Config(void);

void USART_DMA_Config(void);

#endif /* __USART1_H */

bsp_usart_dma.c

/**

  ******************************************************************************

  * 重定義C庫函數(shù)printf到USART端口，使用DMA模式發(fā)送數(shù)據(jù)

  ******************************************************************************

  */ 

#include "./usart/bsp_usart_dma.h"

uint8_t SendBuff[SENDBUFF_SIZE];

 /**

  * @brief  USART GPIO 配置，工作模式配置。115200 8-N-1

  */

void Debug_USART_Config(void)

{

  GPIO_InitTypeDef GPIO_InitStructure;

  USART_InitTypeDef USART_InitStructure;----------------------------

  RCC_AHB1PeriphClockCmd( DEBUG_USART_RX_GPIO_CLK|DEBUG_USART_TX_GPIO_CLK, ENABLE);

  /* Enable UART clock */

  RCC_APB2PeriphClockCmd(DEBUG_USART_CLK, ENABLE);

  /* Connect PXx to USARTx_Tx*/

  GPIO_PinAFConfig(DEBUG_USART_RX_GPIO_PORT,DEBUG_USART_RX_SOURCE, DEBUG_USART_RX_AF);

  /* Connect PXx to USARTx_Rx*/

  GPIO_PinAFConfig(DEBUG_USART_TX_GPIO_PORT,DEBUG_USART_TX_SOURCE,DEBUG_USART_TX_AF);

  /* Configure USART Tx as alternate function  */

  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

  GPIO_InitStructure.GPIO_Pin = DEBUG_USART_TX_PIN  ;

  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

  GPIO_Init(DEBUG_USART_TX_GPIO_PORT, &GPIO_InitStructure);

  /* Configure USART Rx as alternate function  */

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

  GPIO_InitStructure.GPIO_Pin = DEBUG_USART_RX_PIN;

  GPIO_Init(DEBUG_USART_RX_GPIO_PORT, &GPIO_InitStructure);

  /* USART mode config */

  USART_InitStructure.USART_BaudRate = DEBUG_USART_BAUDRATE;

  USART_InitStructure.USART_WordLength = USART_WordLength_8b;

  USART_InitStructure.USART_StopBits = USART_StopBits_1;

  USART_InitStructure.USART_Parity = USART_Parity_No ;

  USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;

  USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;

  USART_Init(DEBUG_USART, &USART_InitStructure); 

  USART_Cmd(DEBUG_USART, ENABLE);

}

///重定向C庫函數(shù)printf到USART1

int fputc(int ch, FILE *f)

{

        /* 發(fā)送一個字節(jié)數(shù)據(jù)到USART1 */

        USART_SendData(DEBUG_USART, (uint8_t) ch);

        /* 等待發(fā)送完畢 */

        while (USART_GetFlagStatus(DEBUG_USART, USART_FLAG_TXE) == RESET);      

        return (ch);

}

///重定向C庫函數(shù)scanf到USART1

int fgetc(FILE *f)

{

        /* 等待串口輸入數(shù)據(jù) */

        while (USART_GetFlagStatus(DEBUG_USART, USART_FLAG_RXNE) == RESET);

        return (int)USART_ReceiveData(DEBUG_USART);

}

/**

  * @brief  USART1 TX DMA 配置，內存到外設(USART1->DR)

  */

void USART_DMA_Config(void)

{

  DMA_InitTypeDef DMA_InitStructure;

  /*開啟DMA時鐘*/

  RCC_AHB1PeriphClockCmd(DEBUG_USART_DMA_CLK, ENABLE);

  /* 復位初始化DMA數(shù)據(jù)流 */

  DMA_DeInit(DEBUG_USART_DMA_STREAM);

  /* 確保DMA數(shù)據(jù)流復位完成 */

  while (DMA_GetCmdStatus(DEBUG_USART_DMA_STREAM) != DISABLE)  {

  }

  /*USART tx對應DMA2，通道4，數(shù)據(jù)流7*/   

  DMA_InitStructure.DMA_Channel = DEBUG_USART_DMA_CHANNEL;  

  /*設置DMA源，串口數(shù)據(jù)寄存器地址*/

  DMA_InitStructure.DMA_PeripheralBaseAddr = DEBUG_USART_DR_BASE;    

  /*內存地址（要傳輸?shù)淖兞康闹羔槪?/

  DMA_InitStructure.DMA_Memory0BaseAddr = (u32)SendBuff;

  /*方向：內存到外設*/      

  DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;   

  /*傳輸大小DMA_BufferSize=SENDBUFF_SIZE*/  

  DMA_InitStructure.DMA_BufferSize = SENDBUFF_SIZE;

  /*外設地址不增*/        

  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; 

  /*內存地址自增*/

  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;   

  /*外設數(shù)據(jù)單位*/    

  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;

  /*內存數(shù)據(jù)單位 8bit*/

  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;   

  /*DMA模式：循環(huán)*/

  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;    

  /*優(yōu)先級：中*/ 

  DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;      

  /*禁用FIFO*/

  DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;        

  DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;    

  /*存儲器突發(fā)傳輸16個節(jié)拍*/

  DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;    

  /*外設突發(fā)傳輸1個節(jié)拍*/

  DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;    

  /*配置DMA2的數(shù)據(jù)流7*/          

  DMA_Init(DEBUG_USART_DMA_STREAM, &DMA_InitStructure);

  /*使能DMA*/

  DMA_Cmd(DEBUG_USART_DMA_STREAM, ENABLE);

  /*等待DMA數(shù)據(jù)流有效*/

  while(DMA_GetCmdStatus(DEBUG_USART_DMA_STREAM) != ENABLE)

  {

  }   

}

/*********************************************END OF FILE**********************/