STM32F0 TIMER PWM DMA not working.

[parth kothiya]

i want change pwm duty cycle using dma in circular mode but its not changing duty cycle so dma is not working what is the problem in code? how can use PWM + DMA ?

main.c

uint16_t duty[] = {0,100,200,300,400,500,600,700,800,900,1000,900,800,700,600,500,400,300,200,100,0};
 
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_TIM3_Init();
  MX_DMA_Init();
  /* USER CODE BEGIN 2 */
  HAL_TIM_PWM_Start_DMA(&htim3, TIM_CHANNEL_1, (uint32_t*)duty, 21);
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
	while (1)
	{
    /* USER CODE END WHILE */
 
    /* USER CODE BEGIN 3 */
	}
  /* USER CODE END 3 */
}

timer.c

#include "tim.h"
 
/* USER CODE BEGIN 0 */
 
/* USER CODE END 0 */
 
TIM_HandleTypeDef htim3;
DMA_HandleTypeDef hdma_tim3_ch1_trig;
 
/* TIM3 init function */
void MX_TIM3_Init(void)
{
 
  /* USER CODE BEGIN TIM3_Init 0 */
 
  /* USER CODE END TIM3_Init 0 */
 
  TIM_ClockConfigTypeDef sClockSourceConfig = {0};
  TIM_MasterConfigTypeDef sMasterConfig = {0};
  TIM_OC_InitTypeDef sConfigOC = {0};
 
  /* USER CODE BEGIN TIM3_Init 1 */
 
  /* USER CODE END TIM3_Init 1 */
  htim3.Instance = TIM3;
  htim3.Init.Prescaler = 5;
  htim3.Init.CounterMode = TIM_COUNTERMODE_CENTERALIGNED1;
  htim3.Init.Period = 1000;
  htim3.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  htim3.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
  if (HAL_TIM_Base_Init(&htim3) != HAL_OK)
  {
    Error_Handler();
  }
  sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
  if (HAL_TIM_ConfigClockSource(&htim3, &sClockSourceConfig) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_TIM_PWM_Init(&htim3) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim3, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sConfigOC.OCMode = TIM_OCMODE_PWM1;
  sConfigOC.Pulse = 1;
  sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
  sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
  if (HAL_TIM_PWM_ConfigChannel(&htim3, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN TIM3_Init 2 */
 
  /* USER CODE END TIM3_Init 2 */
  HAL_TIM_MspPostInit(&htim3);
 
}
 
void HAL_TIM_Base_MspInit(TIM_HandleTypeDef* tim_baseHandle)
{
 
  if(tim_baseHandle->Instance==TIM3)
  {
  /* USER CODE BEGIN TIM3_MspInit 0 */
 
  /* USER CODE END TIM3_MspInit 0 */
    /* TIM3 clock enable */
    __HAL_RCC_TIM3_CLK_ENABLE();
 
    /* TIM3 DMA Init */
    /* TIM3_CH1_TRIG Init */
    hdma_tim3_ch1_trig.Instance = DMA1_Channel4;
    hdma_tim3_ch1_trig.Init.Direction = DMA_PERIPH_TO_MEMORY;
    hdma_tim3_ch1_trig.Init.PeriphInc = DMA_PINC_DISABLE;
    hdma_tim3_ch1_trig.Init.MemInc = DMA_MINC_ENABLE;
    hdma_tim3_ch1_trig.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
    hdma_tim3_ch1_trig.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
    hdma_tim3_ch1_trig.Init.Mode = DMA_CIRCULAR;
    hdma_tim3_ch1_trig.Init.Priority = DMA_PRIORITY_LOW;
    if (HAL_DMA_Init(&hdma_tim3_ch1_trig) != 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(tim_baseHandle,hdma[TIM_DMA_ID_CC1],hdma_tim3_ch1_trig);
    __HAL_LINKDMA(tim_baseHandle,hdma[TIM_DMA_ID_TRIGGER],hdma_tim3_ch1_trig);
 
  /* USER CODE BEGIN TIM3_MspInit 1 */
 
  /* USER CODE END TIM3_MspInit 1 */
  }
}
void HAL_TIM_MspPostInit(TIM_HandleTypeDef* timHandle)
{
 
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(timHandle->Instance==TIM3)
  {
  /* USER CODE BEGIN TIM3_MspPostInit 0 */
 
  /* USER CODE END TIM3_MspPostInit 0 */
 
    __HAL_RCC_GPIOB_CLK_ENABLE();
    /**TIM3 GPIO Configuration
    PB4     ------> TIM3_CH1
    */
    GPIO_InitStruct.Pin = GPIO_PIN_4;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    GPIO_InitStruct.Alternate = GPIO_AF1_TIM3;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
 
  /* USER CODE BEGIN TIM3_MspPostInit 1 */
 
  /* USER CODE END TIM3_MspPostInit 1 */
  }
 
}
 

dma.c

void MX_DMA_Init(void)
{
 
  /* DMA controller clock enable */
  __HAL_RCC_DMA1_CLK_ENABLE();
 
  /* DMA interrupt init */
  /* DMA1_Channel4_5_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(DMA1_Channel4_5_IRQn, 0, 0);
  HAL_NVIC_EnableIRQ(DMA1_Channel4_5_IRQn);
 
}

[TDK]

> /* TIM3_CH1_TRIG Init */

> hdma_tim3_ch1_trig.Instance = DMA1_Channel4;

> hdma_tim3_ch1_trig.Init.Direction = DMA_PERIPH_TO_MEMORY;

If you want to change the duty cycle, you need to transfer from memory to peripheral.

[parth kothiya]

I change dma direction memory to peripheral and try it but still not changing duty cycle it's remain constant.​

I have configured alternate pins for output that's why it happens? By default pin is PA7 and I configured PB4​ is this cause problem?

[PCamp.2]

delete

[waclawek.jan]

> The CubeIDE for the STM32F0(30F4) does not provide ANY memory to peripheral DMA channels that you can select.

• don't hijack other's threads, start your own and if you feel it's pertinent to other threads, provide links to them
• provide context for your post - relevant code, screenshots, description of the findings and how they differ from expectations
• all DMA channels in F0 can be set to memory-to-peripheral. The DMA chapter in RM also describes, how exactly do individual DMA channels map to individual peripherals. You may have come into conflict with other peripheral already using given DMA channel.

JW

[PCamp.2]

It took you longer to write/copypasta that response than it took to ignore it. (Yes, the irony).

If I'd been allowed to delete my own comment I could have saved your trouble.

[Tomas172000]

Hi, I’m experiencing the same problem. Could you fix it?