dma

只看该作者 · 2014-5-7 11:53

我现在用串口2收GPS数据，I2C读取陀螺仪数据，都使用串口1发送，现配置了串口1的DMA，不知道如何写数据输出正确（GPS是一秒收一次，陀螺仪是100MS读取一次）
DMA_InitTypeDef DMA_InitStructure;
/* DMA clock enable */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);//DMA1
  /* DMA1 Channel4 (triggered by USART1 Tx event) Config */
  DMA_DeInit(DMA1_Channel4);
  DMA_InitStructure.DMA_PeripheralBaseAddr = 0x40013804;
  DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)Gps_Send_Buf;
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
  DMA_InitStructure.DMA_BufferSize = 1024;
  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_InitStructure.DMA_Priority = DMA_Priority_High;
  DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
  DMA_Init(DMA1_Channel4, &DMA_InitStructure);
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);
  DMA_Cmd(DMA1_Channel4, DISABLE);
void DMA1_Channel4_IRQHandler(void)
{
  DMA_ClearITPendingBit(DMA1_IT_TC4);
  DMA_ClearITPendingBit(DMA1_IT_TE4);
  DMA_Cmd(DMA1_Channel4, DISABLE);//??DMA
// USART1_TX_Finish=1;//?DMA????

}

只看该作者 · 2014-5-7 11:55

//Enable DMA Channel4 Interrupt
NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel4_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);