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Timer Compare Output using DMA - STM32F3Discovery

daded.1
Associate II

Hello,

I am attempting to generate a waveform with a period of 33ms. In-between each period, I need to toggle the timer output 5 times with a varying timescale. My initial thought is to do this using a timer in output compare mode and then update the CRR register with the 5 pulses from the DMA in a circular mode.

  ___________          ___________          ___________
  |   5700  |___3000___|   4700  |___3000___|   10000 |_________________________

  <------------------------------------33ms------------------------------------>
  

So far, the pin toggles but at intervals that are over the values in the array. Below is the waveform as seen on a logic analyser. I am certain that the input clock is correct at 36MHz and the period should be 33ms.

daded1_1-1715401969734.png

 

I have included the following functions to the CubeMX generated code to ensure the timer is started with DMA.

HAL_TIM_OC_DelayElapsedCallback(&htim17);
//enable dma
HAL_TIM_OC_Start_DMA(&htim17, TIM_CHANNEL_1, (uint32_t*)wave_buffer, 5);

 At this point, I'm not sure what I'm missing as I've followed the steps in the reference manual and application notes to be on par with what I need. I appreciate any help with what I may be missing, thank you.

PS- code is below

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
**/

/* Private variables ---------------------------------------------------------*/
TIM_HandleTypeDef htim17;
DMA_HandleTypeDef hdma_tim17_ch1_up;

/* USER CODE BEGIN PV */
  uint16_t wave_buffer[5] = {5700, 3000, 4700, 3000, 10000};

/* 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_TIM17_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

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

  /* USER CODE BEGIN 1 */

  /*
  ___________          ___________          ___________
  |   5700  |___3000___|   4700  |___3000___|   10000 |_________________________

  <------------------------------------33ms------------------------------------>
  
  */
  /* 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_TIM17_Init();
  /* USER CODE BEGIN 2 */
  
  // HAL_TIM_OC_DelayElapsedCallback(&htim15);
  HAL_TIM_OC_DelayElapsedCallback(&htim17);
  //enable dma
  HAL_TIM_OC_Start_DMA(&htim17, TIM_CHANNEL_1, (uint32_t*)wave_buffer, 5);

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* 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};

  /** 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.PLLMUL = RCC_PLL_MUL9;
  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_1) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief TIM17 Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_TIM17_Init(void)
{

  /* USER CODE BEGIN TIM17_Init 0 */

  /* USER CODE END TIM17_Init 0 */

  TIM_OC_InitTypeDef sConfigOC = {0};
  TIM_BreakDeadTimeConfigTypeDef sBreakDeadTimeConfig = {0};

  /* USER CODE BEGIN TIM17_Init 1 */

  /* USER CODE END TIM17_Init 1 */
  htim17.Instance = TIM17;
  htim17.Init.Prescaler = 36-1;
  htim17.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim17.Init.Period = 33000-1;
  htim17.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  htim17.Init.RepetitionCounter = 0;
  htim17.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
  if (HAL_TIM_Base_Init(&htim17) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_TIM_OC_Init(&htim17) != HAL_OK)
  {
    Error_Handler();
  }
  sConfigOC.OCMode = TIM_OCMODE_TOGGLE;
  sConfigOC.Pulse = 0;
  sConfigOC.OCPolarity = TIM_OCPOLARITY_LOW;
  sConfigOC.OCNPolarity = TIM_OCNPOLARITY_HIGH;
  sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
  sConfigOC.OCIdleState = TIM_OCIDLESTATE_RESET;
  sConfigOC.OCNIdleState = TIM_OCNIDLESTATE_RESET;
  if (HAL_TIM_OC_ConfigChannel(&htim17, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
  {
    Error_Handler();
  }
  __HAL_TIM_ENABLE_OCxPRELOAD(&htim17, TIM_CHANNEL_1);
  sBreakDeadTimeConfig.OffStateRunMode = TIM_OSSR_DISABLE;
  sBreakDeadTimeConfig.OffStateIDLEMode = TIM_OSSI_DISABLE;
  sBreakDeadTimeConfig.LockLevel = TIM_LOCKLEVEL_OFF;
  sBreakDeadTimeConfig.DeadTime = 0;
  sBreakDeadTimeConfig.BreakState = TIM_BREAK_DISABLE;
  sBreakDeadTimeConfig.BreakPolarity = TIM_BREAKPOLARITY_HIGH;
  sBreakDeadTimeConfig.BreakFilter = 0;
  sBreakDeadTimeConfig.AutomaticOutput = TIM_AUTOMATICOUTPUT_DISABLE;
  if (HAL_TIMEx_ConfigBreakDeadTime(&htim17, &sBreakDeadTimeConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN TIM17_Init 2 */

  /* USER CODE END TIM17_Init 2 */
  HAL_TIM_MspPostInit(&htim17);

}

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

  /* DMA controller clock 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
  * @PAram None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
/* 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();

/* 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.
  * @PAram  file: pointer to the source file name
  * @PAram  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 */

 

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file         stm32f3xx_hal_msp.c
  * @brief        This file provides code for the MSP Initialization
  *               and de-Initialization codes.
  ******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "main.h"

extern DMA_HandleTypeDef hdma_tim17_ch1_up;

void HAL_TIM_MspPostInit(TIM_HandleTypeDef *htim);
                    /**
  * Initializes the Global MSP.
  */
void HAL_MspInit(void)
{

  /* USER CODE BEGIN MspInit 0 */

  /* USER CODE END MspInit 0 */

  __HAL_RCC_SYSCFG_CLK_ENABLE();
  __HAL_RCC_PWR_CLK_ENABLE();

  /* System interrupt init*/

  /* USER CODE BEGIN MspInit 1 */

  /* USER CODE END MspInit 1 */
}

/**
* @brief TIM_Base MSP Initialization
* This function configures the hardware resources used in this example
* @PAram htim_base: TIM_Base handle pointer
* @retval None
*/
void HAL_TIM_Base_MspInit(TIM_HandleTypeDef* htim_base)
{
  if(htim_base->Instance==TIM17)
  {
  /* USER CODE BEGIN TIM17_MspInit 0 */

  /* USER CODE END TIM17_MspInit 0 */
    /* Peripheral clock enable */
    __HAL_RCC_TIM17_CLK_ENABLE();

    /* TIM17 DMA Init */
    /* TIM17_CH1_UP Init */
    hdma_tim17_ch1_up.Instance = DMA1_Channel1;
    hdma_tim17_ch1_up.Init.Direction = DMA_MEMORY_TO_PERIPH;
    hdma_tim17_ch1_up.Init.PeriphInc = DMA_PINC_DISABLE;
    hdma_tim17_ch1_up.Init.MemInc = DMA_MINC_ENABLE;
    hdma_tim17_ch1_up.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
    hdma_tim17_ch1_up.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
    hdma_tim17_ch1_up.Init.Mode = DMA_CIRCULAR;
    hdma_tim17_ch1_up.Init.Priority = DMA_PRIORITY_HIGH;
    if (HAL_DMA_Init(&hdma_tim17_ch1_up) != HAL_OK)
    {
      Error_Handler();
    }

    /* Several peripheral DMA handle pointers point to the same DMA handle.
     Be aware that there is only one channel to perform all the requested DMAs. */
    __HAL_LINKDMA(htim_base,hdma[TIM_DMA_ID_CC1],hdma_tim17_ch1_up);
    __HAL_LINKDMA(htim_base,hdma[TIM_DMA_ID_UPDATE],hdma_tim17_ch1_up);

    /* TIM17 interrupt Init */
    HAL_NVIC_SetPriority(TIM1_TRG_COM_TIM17_IRQn, 0, 0);
    HAL_NVIC_EnableIRQ(TIM1_TRG_COM_TIM17_IRQn);
  /* USER CODE BEGIN TIM17_MspInit 1 */

  /* USER CODE END TIM17_MspInit 1 */
  }

}

void HAL_TIM_MspPostInit(TIM_HandleTypeDef* htim)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(htim->Instance==TIM17)
  {
  /* USER CODE BEGIN TIM17_MspPostInit 0 */

  /* USER CODE END TIM17_MspPostInit 0 */

    __HAL_RCC_GPIOA_CLK_ENABLE();
    /**TIM17 GPIO Configuration
    PA7     ------> TIM17_CH1
    */
    GPIO_InitStruct.Pin = GPIO_PIN_7;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    GPIO_InitStruct.Alternate = GPIO_AF1_TIM17;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /* USER CODE BEGIN TIM17_MspPostInit 1 */

  /* USER CODE END TIM17_MspPostInit 1 */
  }

}
/**
* @brief TIM_Base MSP De-Initialization
* This function freeze the hardware resources used in this example
* @PAram htim_base: TIM_Base handle pointer
* @retval None
*/
void HAL_TIM_Base_MspDeInit(TIM_HandleTypeDef* htim_base)
{
  if(htim_base->Instance==TIM17)
  {
  /* USER CODE BEGIN TIM17_MspDeInit 0 */

  /* USER CODE END TIM17_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_TIM17_CLK_DISABLE();

    /* TIM17 DMA DeInit */
    HAL_DMA_DeInit(htim_base->hdma[TIM_DMA_ID_CC1]);
    HAL_DMA_DeInit(htim_base->hdma[TIM_DMA_ID_UPDATE]);

    /* TIM17 interrupt DeInit */
    HAL_NVIC_DisableIRQ(TIM1_TRG_COM_TIM17_IRQn);
  /* USER CODE BEGIN TIM17_MspDeInit 1 */

  /* USER CODE END TIM17_MspDeInit 1 */
  }

}

/* USER CODE BEGIN 1 */

/* USER CODE END 1 */

 

 

daded1_3-1715402159278.png

 

 

daded1_4-1715402178719.png

 

daded1_5-1715402229843.png

 

 

4 REPLIES 4
Sarra.S
ST Employee

Hello @daded.1

You're on the right track with using HAL_TIM_OC_Start_DMA(), this function allows you to update the CCR with the values provided in the wave_buffer array using DMA and starts the timer in output compare mode.

In the DMA config, the DMA needs to be set to circular mode to reload the wave_buffer values when it reaches the end automatically.

Also, you may want to implement HAL_TIM_OC_DelayElapsedCallback to handle the DMA interrupt on each toggle event

To understand how every function works, you can look at its prototype in the stm32f3xx_hal_tim.c file and read the comments explaining its parameters

Regarding refreshing your memory, refer to the following links: 

Description of STM32F3 HAL and low-layer drivers

STM32CubeMX for STM32 configuration and initialization C code generation

 

Hope that helps!

 

To give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

daded.1
Associate II

Thank you Sarra.S,

That was very insightful. After reading the manuals and going through the prototypes, I went ahead to enable the timer/dma using 

 

HAL_TIM_OC_Start_DMA(&htim15, TIM_CHANNEL_1, (uint16_t*)wave_buffer, 5);

 

I ran the code and I can see the output pin toggle, but it is nothing compared to the expected pulses. On reset, it just toggles at a period of 2 times the set period.

As for DMA config, I have that set as follows in the CubeMX generated file

 

    /* Peripheral clock enable */
    __HAL_RCC_TIM15_CLK_ENABLE();

    /* TIM15 DMA Init */
    /* TIM15_CH1_UP_TRIG_COM Init */
    hdma_tim15_ch1_up_trig_com.Instance = DMA1_Channel5;
    hdma_tim15_ch1_up_trig_com.Init.Direction = DMA_MEMORY_TO_PERIPH;
    hdma_tim15_ch1_up_trig_com.Init.PeriphInc = DMA_PINC_DISABLE;
    hdma_tim15_ch1_up_trig_com.Init.MemInc = DMA_MINC_ENABLE;
    hdma_tim15_ch1_up_trig_com.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
    hdma_tim15_ch1_up_trig_com.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
    hdma_tim15_ch1_up_trig_com.Init.Mode = DMA_CIRCULAR;
    hdma_tim15_ch1_up_trig_com.Init.Priority = DMA_PRIORITY_HIGH;
    if (HAL_DMA_Init(&hdma_tim15_ch1_up_trig_com) != HAL_OK)
    {
      Error_Handler();
    }

 

Now, I am not sure if that is all that is necessary since CubeMX has done a lot of the heavy lifting, but do I need to manually set the DMA peripheral/memory base address, direction or buffer size? Also, is there something I could be missing as regards implementing interrupts? I appreciate any help/advise with this.

Thank you!

--------------------------------- code below ---------------------------------

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2024 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 */

/* USER CODE END Includes */

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

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */

/* USER CODE END PD */

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

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
TIM_HandleTypeDef htim15;
DMA_HandleTypeDef hdma_tim15_ch1_up_trig_com;

/* USER CODE BEGIN PV */

/* 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_TIM15_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

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

  /* USER CODE BEGIN 1 */
  uint16_t wave_buffer[5] = {5700, 3000, 4700, 3000, 10000};

  /*
  ___________          ___________          ___________
  |   5700  |___3000___|   4700  |___3000___|   10000 |_________________________

  <------------------------------------33ms------------------------------------>
  
  */
  
  /* 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_TIM15_Init();
  /* USER CODE BEGIN 2 */
  HAL_TIM_OC_DelayElapsedCallback(&htim15);
  //enable dma
  HAL_TIM_OC_Start_DMA(&htim15, TIM_CHANNEL_1, (uint16_t*)wave_buffer, 5);
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* 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};

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
  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_2) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief TIM15 Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_TIM15_Init(void)
{

  /* USER CODE BEGIN TIM15_Init 0 */

  /* USER CODE END TIM15_Init 0 */

  TIM_ClockConfigTypeDef sClockSourceConfig = {0};
  TIM_MasterConfigTypeDef sMasterConfig = {0};
  TIM_OC_InitTypeDef sConfigOC = {0};
  TIM_BreakDeadTimeConfigTypeDef sBreakDeadTimeConfig = {0};

  /* USER CODE BEGIN TIM15_Init 1 */

  /* USER CODE END TIM15_Init 1 */
  htim15.Instance = TIM15;
  htim15.Init.Prescaler = 72-1; // lower internal clock of 72MHz to 1MHz
  htim15.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim15.Init.Period = 33000; // each full wave period is 33ms
  htim15.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  htim15.Init.RepetitionCounter = 0;
  htim15.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
  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();
  }
  if (HAL_TIM_OC_Init(&htim15) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_OC1REF;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim15, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }

  // output compare parameters
  sConfigOC.OCMode = TIM_OCMODE_TOGGLE;
  sConfigOC.Pulse = 0;
  sConfigOC.OCPolarity = TIM_OCPOLARITY_LOW;
  sConfigOC.OCNPolarity = TIM_OCNPOLARITY_HIGH;
  sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
  sConfigOC.OCIdleState = TIM_OCIDLESTATE_RESET;
  sConfigOC.OCNIdleState = TIM_OCNIDLESTATE_RESET;
  if (HAL_TIM_OC_ConfigChannel(&htim15, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
  {
    Error_Handler();
  }
  __HAL_TIM_ENABLE_OCxPRELOAD(&htim15, TIM_CHANNEL_1);
  sBreakDeadTimeConfig.OffStateRunMode = TIM_OSSR_DISABLE;
  sBreakDeadTimeConfig.OffStateIDLEMode = TIM_OSSI_DISABLE;
  sBreakDeadTimeConfig.LockLevel = TIM_LOCKLEVEL_OFF;
  sBreakDeadTimeConfig.DeadTime = 0;
  sBreakDeadTimeConfig.BreakState = TIM_BREAK_DISABLE;
  sBreakDeadTimeConfig.BreakPolarity = TIM_BREAKPOLARITY_HIGH;
  sBreakDeadTimeConfig.BreakFilter = 0;
  sBreakDeadTimeConfig.AutomaticOutput = TIM_AUTOMATICOUTPUT_DISABLE;
  if (HAL_TIMEx_ConfigBreakDeadTime(&htim15, &sBreakDeadTimeConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN TIM15_Init 2 */
  
  /* USER CODE END TIM15_Init 2 */
  HAL_TIM_MspPostInit(&htim15);
  // connect dma
  HAL_TIM_OC_Start_DMA(&htim15, TIM_CHANNEL_1, &wave_buffer, 5);
}

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

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

  /* DMA interrupt init */
  /* DMA1_Channel5_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(DMA1_Channel5_IRQn, 0, 0);
  HAL_NVIC_EnableIRQ(DMA1_Channel5_IRQn);

 

}

/**
  * @brief GPIO Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
/* USER CODE BEGIN MX_GPIO_Init_1 */
/* USER CODE END MX_GPIO_Init_1 */

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

/* 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.
  * @PAram  file: pointer to the source file name
  * @PAram  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 */

  

I don't use Cube/CubeMX and don't try to understand your code, but IMO you want to do 6 transitions (toggles) per timer period, so you should have:

- 6 values in the table:

 

uint16_t wave_buffer[6] = {5700, 3000, 4700, 3000, 10000, 0};

 

- trigger DMA *only* from the CCx event, *not* from Update event

JW

PS. Don't start new thread for the same problem