求助，STM32F4 DMA可否一个外设触发读取另一外设寄存器值

可乐不加冰 · 发表于 2020-11-24 20:13:26

如题，现在使用STM32F407，TIM4输入捕获，触发DMA，外设地址到存储器地址。外设地址为TIM9->CNT

  DMA_DeInit(DMA1_Stream0);
  DMA_InitStructure.DMA_Channel = DMA_Channel_2;
  DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)(&TIM9->CNT);  // (uint32_t)(&TIM4->CNT);  //DMAíaéèμØÖ·
  DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)time1;
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
  DMA_InitStructure.DMA_BufferSize = 2;
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
  DMA_InitStructure.DMA_MemoryDataSize = DMA_PeripheralDataSize_Word;
  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
  DMA_InitStructure.DMA_Priority = DMA_Priority_High;
  DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
  DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;
  DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
  DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
  DMA_Init(DMA1_Stream0, &DMA_InitStructure);

  DMA_Cmd(DMA1_Stream0, ENABLE);

  TIM4_ICInitStructure.TIM_Channel = TIM_Channel_1;
  TIM4_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
  TIM4_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
  TIM4_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
  TIM4_ICInitStructure.TIM_ICFilter = 0x00;
  TIM_ICInit(TIM4, &TIM4_ICInitStructure);

  TIM_DMACmd(TIM4, TIM_DMA_CC1, ENABLE);

  TIM_Cmd(TIM4, ENABLE);

看DMA框图，应该是可以访问到任何外设的。但是DMA_PeripheralBaseAddr是TIM4时，可以正常读入；是TIM9时不能正常读取。
求助，thk