STM32G4 DAC DMA Callbacks Not Firing (HAL_DAC_ConvCpltCallbackCh1 / HalfCplt)

[VadIzmal]

I'm working with an STM32G431KBUx and trying to output a waveform via DAC1 using DMA and TIM6 as trigger (TRGO). I’ve successfully configured the DAC and DMA using STM32CubeMX. 

However, the DMA callbacks HAL_DAC_ConvCpltCallbackCh1 and HAL_DAC_ConvHalfCpltCallbackCh1 never get called.

Here’s what I’ve checked so far:

• DMA handle is linked manually:
  hdac1.DMA_Handle1 = &hdma_dac1_ch1;

• Trigger is set to Timer 6 Trigger Out event.

• DMA is configured in Circular Mode.

• I'm calling HAL_DAC_Start_DMA(...) with a buffer of 2 * 64 samples (12-bit aligned).

• Callback functions are correctly named and defined in main.c:

void HAL_DAC_ConvHalfCpltCallbackCh1(DAC_HandleTypeDef *hdac1) {
// Never called
}
void HAL_DAC_ConvCpltCallbackCh1(DAC_HandleTypeDef *hdac1) {
// Never called
}

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2025 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include <stdio.h>
/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
#define DMA_BUFFER_SIZE 64
#define SAMPLE_FREQ 10000
#define OUTPUT_MID 2048
/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
DAC_HandleTypeDef hdac1;
DMA_HandleTypeDef hdma_dac1_ch1;

TIM_HandleTypeDef htim6;

/* USER CODE BEGIN PV */

//const float two_pi = 2 * M_PI;

uint32_t loop_cnt = 0;
uint32_t cb_cnt = 0;
uint32_t cb_full = 0;
uint32_t cb_half = 0;

uint16_t dma_buffer[2 * DMA_BUFFER_SIZE];

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_DMA_Init(void);
static void MX_TIM6_Init(void);
static void MX_DAC1_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
inline void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim) {
    if (htim->Instance == htim6.Instance) {
        //++cb_cnt;
        //GPIOA->ODR ^= GPIO_PIN_5;
        //HAL_GPIO_TogglePin(GPIOA, GPIO_PIN_5);
    }
}

void do_dac(uint16_t *buffer) {
    for (int i = 0; i < DMA_BUFFER_SIZE; ++i) {
        buffer[i] = (uint16_t)((4095.0f * i) / (DMA_BUFFER_SIZE - 1));  // Пила от 0 до 4095
    }
}

//void HAL_DAC_ConvCpltCallback(DAC_HandleTypeDef *hdac1) {
void HAL_DAC_ConvCpltCallbackCh1(DAC_HandleTypeDef *hdac1) {
    //++cb_full;
//    HAL_GPIO_TogglePin(GPIOA, GPIO_PIN_5);
	GPIOA->ODR ^= GPIO_PIN_5;
    //do_dac(&dma_buffer[DMA_BUFFER_SIZE]);
}

//void HAL_DAC_ConvHalfCpltCallback(DAC_HandleTypeDef *hdac1) {
void HAL_DAC_ConvHalfCpltCallbackCh1(DAC_HandleTypeDef *hdac1) {
	//++cb_half;
//	HAL_GPIO_TogglePin(GPIOA, GPIO_PIN_5);
	GPIOA->ODR ^= GPIO_PIN_5;
	//do_dac(&dma_buffer[0]);
}


/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{

  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_DMA_Init();
  MX_TIM6_Init();
  MX_DAC1_Init();
  /* USER CODE BEGIN 2 */

  HAL_TIM_Base_Start_IT(&htim6);

  hdac1.DMA_Handle1 = &hdma_dac1_ch1;

  HAL_StatusTypeDef res;
  res = HAL_DAC_Start_DMA(&hdac1, DAC_CHANNEL_1, (uint32_t*)dma_buffer, 2 * DMA_BUFFER_SIZE, DAC_ALIGN_12B_R);
  if (res != HAL_OK) {
      HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_SET);  // включи навсегда, если ошибка
      Error_Handler();
  }

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */

  //uint32_t now = 0, next_tick = 1000;

  while (1)
  {
	  //now = HAL_GetTick();
//	  now = uwTick;
//
//	  if (now >= next_tick) {
//
//		  printf("Tick %lu (loop=%lu cb=%lu half=%lu full=%lu)\n", now / 1000, loop_cnt, cb_cnt, cb_half, cb_full);
//
//		  loop_cnt = 0;
//		  next_tick = now + 1000;
//
//
//	  }
//
//	  ++loop_cnt;

//	  HAL_GPIO_TogglePin(GPIOA, GPIO_PIN_5);
	  HAL_Delay(5000);
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Configure the main internal regulator output voltage
  */
  HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1_BOOST);

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV4;
  RCC_OscInitStruct.PLL.PLLN = 85;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
  RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
  RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief DAC1 Initialization Function
  *  None
  * @retval None
  */
static void MX_DAC1_Init(void)
{

  /* USER CODE BEGIN DAC1_Init 0 */

  /* USER CODE END DAC1_Init 0 */

  DAC_ChannelConfTypeDef sConfig = {0};

  /* USER CODE BEGIN DAC1_Init 1 */

  /* USER CODE END DAC1_Init 1 */

  /** DAC Initialization
  */
  hdac1.Instance = DAC1;
  if (HAL_DAC_Init(&hdac1) != HAL_OK)
  {
    Error_Handler();
  }

  /** DAC channel OUT1 config
  */
  sConfig.DAC_HighFrequency = DAC_HIGH_FREQUENCY_INTERFACE_MODE_DISABLE;
  sConfig.DAC_DMADoubleDataMode = DISABLE;
  sConfig.DAC_SignedFormat = DISABLE;
  sConfig.DAC_SampleAndHold = DAC_SAMPLEANDHOLD_DISABLE;
  sConfig.DAC_Trigger = DAC_TRIGGER_T6_TRGO;
  sConfig.DAC_Trigger2 = DAC_TRIGGER_NONE;
  sConfig.DAC_OutputBuffer = DAC_OUTPUTBUFFER_ENABLE;
  sConfig.DAC_ConnectOnChipPeripheral = DAC_CHIPCONNECT_EXTERNAL;
  sConfig.DAC_UserTrimming = DAC_TRIMMING_FACTORY;
  if (HAL_DAC_ConfigChannel(&hdac1, &sConfig, DAC_CHANNEL_1) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN DAC1_Init 2 */

  /* USER CODE END DAC1_Init 2 */

}

/**
  * @brief TIM6 Initialization Function
  *  None
  * @retval None
  */
static void MX_TIM6_Init(void)
{

  /* USER CODE BEGIN TIM6_Init 0 */

  /* USER CODE END TIM6_Init 0 */

  TIM_MasterConfigTypeDef sMasterConfig = {0};

  /* USER CODE BEGIN TIM6_Init 1 */

  /* USER CODE END TIM6_Init 1 */
  htim6.Instance = TIM6;
  htim6.Init.Prescaler = 128;
  htim6.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim6.Init.Period = 65535;
  htim6.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
  if (HAL_TIM_Base_Init(&htim6) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_UPDATE;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim6, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN TIM6_Init 2 */

  /* USER CODE END TIM6_Init 2 */

}

/**
  * Enable DMA controller clock
  */
static void MX_DMA_Init(void)
{

  /* DMA controller clock enable */
  __HAL_RCC_DMAMUX1_CLK_ENABLE();
  __HAL_RCC_DMA1_CLK_ENABLE();

  /* DMA interrupt init */
  /* DMA1_Channel1_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(DMA1_Channel1_IRQn, 0, 0);
  HAL_NVIC_EnableIRQ(DMA1_Channel1_IRQn);

}

/**
  * @brief GPIO Initialization Function
  *  None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  /* USER CODE BEGIN MX_GPIO_Init_1 */

  /* USER CODE END MX_GPIO_Init_1 */

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOF_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pin : LED_Pin */
  GPIO_InitStruct.Pin = LED_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(LED_GPIO_Port, &GPIO_InitStruct);

  /* USER CODE BEGIN MX_GPIO_Init_2 */

  /* USER CODE END MX_GPIO_Init_2 */
}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}

#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  *   file: pointer to the source file name
  *   line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

[KnarfB]

You may find the raw interrupt handler in the *_it.c file which dispatches the irq to HAL. Set a breakpoint there and, if it is hit, follow the path through HAL.

hdac1.DMA_Handle1 = &hdma_dac1_ch1; is should not be needed. See __HAL_LINKDMA in HAL_DAC_MspInit.

How are the DMA settings? Maybe you add the .ioc.

hth

KnarfB

[VadIzmal]

.ioc file is attached

[KnarfB · Accepted solution]

After reading STM32G431KB DAC DMA not working - Page 3 - STMicroelectronics Community

in the DMA setup, change Data With for the Peripheral to Word.

hth

KnarfB 

[TDK]

Is the DAC working as expected? Is the NDTR register changing? Is the Timer CNT register changing? The rate of samples is pretty low. It'll take a few seconds for a half-buffer to be pushed out.