SDRAM DMA 到 TIM2->ARR 数据搬移错误

乔布斯 · 发表于 2020-9-24 07:27:37

本帖最后由乔布斯于 2020-9-24 09:26 编辑

芯片是STM32H743,没有启用cache，也没配置mpu
用 DMA1_Stream2,由TIM2 update 触发，更新 tim2->arr 的值，以便在特定的时刻发出pwm脉冲
由于数据较多，数据保存在 SDRAM里面，是32位数据，指定在0xC0000000位置，应该也是4字节对齐了

目前现象是，当数据在stm32自身内存中时，数据搬移正确，波形正常
当数据在SDRAM里面时，搬移后读取 tim2->arr的值，数据错误，在debug模式下，偶尔也能发现有正确数据
当把dma改为memory to memory，地址都递增时，从sdram搬到stm32自身内存，数据是正确的

HAL_DMA_Start_IT(&hdma_tim2_up, (uint32_t) STM32_BUFFER1,(uint32_t)(&(TIM2->ARR)),3200);    //搬移正确
HAL_DMA_Start_IT(&hdma_tim2_up, (uint32_t) SDRAM_BUFFER,(uint32_t)(&(TIM2->ARR)),32000);    //数据不对
HAL_DMA_Start_IT(&hdma_tim2_up, (uint32_t) SDRAM_BUFFER,(uint32_t)(STM32_BUFFER2),32000); //搬移正确

//数据更新周期约2.5ms，延时5-6mm能间隔取到ARR值

  MyDmaStart(0);

  osDelay(6);
      arr1=TIM2->ARR;A
  osDelay(6);
      arr2=TIM2->ARR;
  osDelay(5);
      arr3=TIM2->ARR;
  osDelay(6);
      arr4=TIM2->ARR;
  osDelay(5);
      arr5=TIM2->ARR;
  osDelay(6);
      arr6=TIM2->ARR;

正常值在 0x00002B00附近, 十进制500到1000
非正常值发现有 0x00A002A4,有时是别的数据，不稳定
debug跟踪，sdram有时也能出正常数据，运行时没发现过正常的

请问，应该从哪些地方入手调试？

SDRAM配置是用的原子的数据，
void MX_FMC_Init(void)
{
  FMC_SDRAM_TimingTypeDef SdramTiming = {0};

  /** Perform the SDRAM1 memory initialization sequence
  */
  hsdram1.Instance = FMC_SDRAM_DEVICE;
  /* hsdram1.Init */
  hsdram1.Init.SDBank = FMC_SDRAM_BANK1;
  hsdram1.Init.ColumnBitsNumber = FMC_SDRAM_COLUMN_BITS_NUM_9;
  hsdram1.Init.RowBitsNumber = FMC_SDRAM_ROW_BITS_NUM_13;
  hsdram1.Init.MemoryDataWidth = FMC_SDRAM_MEM_BUS_WIDTH_16;
  hsdram1.Init.InternalBankNumber = FMC_SDRAM_INTERN_BANKS_NUM_4;
  hsdram1.Init.CASLatency = FMC_SDRAM_CAS_LATENCY_2;
  hsdram1.Init.WriteProtection = FMC_SDRAM_WRITE_PROTECTION_DISABLE;
  hsdram1.Init.SDClockPeriod = FMC_SDRAM_CLOCK_PERIOD_2;
  hsdram1.Init.ReadBurst = FMC_SDRAM_RBURST_ENABLE;
  hsdram1.Init.ReadPipeDelay = FMC_SDRAM_RPIPE_DELAY_0;
  /* SdramTiming */
  SdramTiming.LoadToActiveDelay = 2;
  SdramTiming.ExitSelfRefreshDelay = 8;
  SdramTiming.SelfRefreshTime = 6;
  SdramTiming.RowCycleDelay = 6;
  SdramTiming.WriteRecoveryTime = 5;
  SdramTiming.RPDelay = 2;
  SdramTiming.RCDDelay = 2;

  if (HAL_SDRAM_Init(&hsdram1, &SdramTiming) != HAL_OK)
  {
Error_Handler( );
  }

}

////////////////////////////////
main中调用  SDRAM_Initialization_Sequence：

  MX_FMC_Init();
  MX_TIM2_Init();
  /* USER CODE BEGIN 2 */

  SDRAM_Initialization_Sequence(&hsdram1);
  ValueInit();

  /* USER CODE END 2 */

  /* Init scheduler */
  osKernelInitialize();  /* Call init function for freertos objects (in freertos.c) */
  MX_FREERTOS_Init();

///////////////////////////////////////
freertos task 中启动dma并检查数据

void StartTaskLed(void *argument)
{
  /* USER CODE BEGIN StartTaskLed */
  /* Infinite loop */
      osDelay(2000);

  MyDmaStart(0);
  osDelay(6);
      arr1=TIM2->ARR;
  osDelay(6);
      arr2=TIM2->ARR;
  osDelay(5);
      arr3=TIM2->ARR;
  osDelay(6);
      arr4=TIM2->ARR;
  osDelay(5);
      arr5=TIM2->ARR;
  osDelay(6);
      arr6=TIM2->ARR;

  for(;;)
  {