STM32H723- DMA DAC仅适用于常量？

Question

在STM32G4中，我可以设置DMA，这样我就可以使用常规变量(即，uint8_t数组)。但是，当我尝试将我的代码移植到H723上时，DAC将无法工作，除非它使用常量变量(即。const uint8_t数组)，在运行时之前设置。我的应用程序需要在运行时更改数组。数组的指针初始化似乎不起作用。我想知道有没有办法解决这个问题？我被常量变量卡住了吗？谢谢!

EDIT1: DAC DMA和计时器的当前设置

static void MX_DAC1_Init(void){
  DAC_ChannelConfTypeDef sConfig = {0};
  hdac1.Instance = DAC1;
  if (HAL_DAC_Init(&hdac1) != HAL_OK){
    Error_Handler();
  }
  sConfig.DAC_SampleAndHold = DAC_SAMPLEANDHOLD_DISABLE;
  sConfig.DAC_Trigger = DAC_TRIGGER_T15_TRGO;
  sConfig.DAC_OutputBuffer = DAC_OUTPUTBUFFER_DISABLE;
  sConfig.DAC_ConnectOnChipPeripheral = DAC_CHIPCONNECT_ENABLE;
  sConfig.DAC_UserTrimming = DAC_TRIMMING_FACTORY;
  if (HAL_DAC_ConfigChannel(&hdac1, &sConfig, DAC_CHANNEL_2) != HAL_OK)
  {
    Error_Handler();
  }
}

Timer15配置：

static void MX_TIM15_Init(void)
{ TIM_ClockConfigTypeDef sClockSourceConfig = {0};
  TIM_MasterConfigTypeDef sMasterConfig = {0};

  htim15.Instance = TIM15;
  htim15.Init.Prescaler = 55-1;
  htim15.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim15.Init.Period = 10-1;
  htim15.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  htim15.Init.RepetitionCounter = 0;
  htim15.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
  if (HAL_TIM_Base_Init(&htim15) != HAL_OK)
  {
    Error_Handler();
  }
  sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
  if (HAL_TIM_ConfigClockSource(&htim15, &sClockSourceConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_UPDATE;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim15, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
}

DMA配置：

static void MX_DMA_Init(void){
 __HAL_RCC_DMA1_CLK_ENABLE();

  HAL_NVIC_SetPriority(DMA1_Stream5_IRQn, 0, 0);
  HAL_NVIC_EnableIRQ(DMA1_Stream5_IRQn);
  /* DMAMUX1_OVR_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(DMAMUX1_OVR_IRQn, 0, 0);
  HAL_NVIC_EnableIRQ(DMAMUX1_OVR_IRQn);

}

在main函数中：

int main(void){
  MX_DAC1_Init();
  MX_TIM15_Init();
  MX_OPAMP2_Init();
  
  /* USER CODE BEGIN 2 */
  set_sine(dac_data1, NUM_DAC_POINTS) //Set a max amplitude uniformly over number of points, dac_data is initialized as uint8_t dac_data1[NUM_DAC_POINTS];
  HAL_TIM_Base_Start(&htim15); //Start the timer for DAC DMA Transfer
  HAL_DAC_Init(&hdac1);
  (HAL_DAC_Start_DMA(&hdac1, DAC_CHANNEL_2, (uint32_t *)dac_data1, NUM_DAC_POINTS, DAC_ALIGN_8B_R);
}

这种设置不起作用，但只需将dac_data1初始化为const uint8_t并预定义它，DMA就能起作用。

Answer 1

好的，感谢Tom V对不同内存库的见解。在我的例子中，dac_data1放在RAM上，在参考手册中也称为DTCMRAM。DMA无法访问DTCMRAM，但它被选为H7上运行时操作的默认内存位置。需要对链接器文件(在我的例子中是..._FLASH.ld和..._RAM.ld)进行修改。我将.bss、.data和._user_heap_stack的内存位置从RAM更改为RAM_D1。这是直接取自：https://community.st.com/s/article/FAQ-DMA-is-not-working-on-STM32H7-devices