usart1实现DMA出现的接收问题

只看该作者 · 2013-3-13 11:23

void DMA_Config_Recv(void)
{
   DMA_InitTypeDef DMA_InitStructure;
   // DMA clock enable //
   RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);//DMA1
   DMA_DeInit(DMA1_Channel5);
   DMA_InitStructure.DMA_PeripheralBaseAddr = PERIPH_ADDR_USART1_DR ;
   DMA_InitStructure.DMA_MemoryBaseAddr    = (uint32_t)pCmdDoubleList->CurBufStr.s_uintRecvBufAddr ;  //See "usart_dma.h"
   DMA_InitStructure.DMA_DIR                = DMA_DIR_PeripheralSRC;
   DMA_InitStructure.DMA_BufferSize          = DMA_BUF_LEN ;       //See "usart_dma.h"
   DMA_InitStructure.DMA_PeripheralInc       = DMA_PeripheralInc_Disable;
   DMA_InitStructure.DMA_MemoryInc          = DMA_MemoryInc_Enable;
   DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
   DMA_InitStructure.DMA_MemoryDataSize    = DMA_MemoryDataSize_Byte;
   DMA_InitStructure.DMA_Mode                = DMA_Mode_Normal ;          // DMA_Mode_Circular;
   DMA_InitStructure.DMA_Priority          = DMA_Priority_VeryHigh ;    //DMA_Priority_High;
   DMA_InitStructure.DMA_M2M                = DMA_M2M_Disable;
   DMA_Init(DMA1_Channel5, &DMA_InitStructure);
   DMA_ITConfig(DMA1_Channel5, DMA_IT_TC, ENABLE);
   DMA_ITConfig(DMA1_Channel5, DMA_IT_TE, ENABLE);
   // Enable USART1 DMA RX request //
   USART_DMACmd(USART1, USART_DMAReq_Rx, ENABLE);
   DMA_Cmd(DMA1_Channel5, ENABLE);  //Enable Rx

}

只看该作者 · 2013-3-13 11:24

宏定义
#define  DMA_BUF_NUM          16       //
#define  DMA_BUF_LEN          96       //  The MAX number DMA rx data , which should more length than the expected one (i.e. Usart rx-data is N, here is the M , M>N)

DMA_InitStructure.DMA_MemoryBaseAddr    用具体的接收数组进行初始化

只看该作者 · 2013-3-13 11:28

本帖最后由 pybieku 于 2013-3-13 11:30 编辑

#define  DMA_BUFFER_LEN_TX    16
unsigned char USART_DMA_InitBuf[] = "DMA_Config First!" ;

void DMA_Config_Send(void)
{
      DMA_InitTypeDef DMA_InitStructure;
      DMA_DeInit(DMA1_Channel4); // Reset the Register of DMA1_Ch4
      // DMA Mapping  USART1_TX  <==> DMA1_Ch4
      DMA_InitStructure.DMA_PeripheralBaseAddr = PERIPH_ADDR_USART1_DR ;
      DMA_InitStructure.DMA_MemoryBaseAddr    = (uint32_t)((unsigned char*)USART_DMA_InitBuf) ;  //每次都不一样，需要更新!!!

      DMA_InitStructure.DMA_DIR             = DMA_DIR_PeripheralDST;    // see "stm32f10x_dma.h"       :  from Memory to Peripheral
      DMA_InitStructure.DMA_BufferSize       = DMA_BUFFER_LEN_TX ;//每次都不一样，需要更新!!!
      DMA_InitStructure.DMA_PeripheralInc    = DMA_PeripheralInc_Disable;
      DMA_InitStructure.DMA_MemoryInc       = DMA_MemoryInc_Enable;
      DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
      DMA_InitStructure.DMA_MemoryDataSize    = DMA_MemoryDataSize_Byte;
      DMA_InitStructure.DMA_Mode             = DMA_Mode_Normal ;                      // DMA_Mode_Circular
      DMA_InitStructure.DMA_Priority          = DMA_Priority_High ;       //10 for high priority.
      DMA_InitStructure.DMA_M2M             = DMA_M2M_Disable ;
      DMA_Init(DMA1_Channel4, &DMA_InitStructure);
      //enable the DMA interrupt both  transfer-complete and transfer-error
      DMA_ITConfig(DMA1_Channel4, DMA_IT_TC, ENABLE);
      DMA_ITConfig(DMA1_Channel4, DMA_IT_TE, ENABLE);
      // Enable USART1 DMA TX request //
      USART_DMACmd(USART1, USART_DMAReq_Tx, ENABLE);
      // init disable DMA
      DMA_Cmd(DMA1_Channel4, DISABLE);       //收到有效的数据包后，会有发允许标志，然后才启动发送！！！ MAIN function DOES THIS JOB!
}