I have followed this tutorial without success:
https://controllerstech.com/pwm-with-dma-in-stm32/
Please take a look at my code:
TIM init:
/**
* @brief TIM2 Initialization Function
* @param None
* @retval None
*/
static void MX_TIM2_Init(void)
{
/* USER CODE BEGIN TIM2_Init 0 */
/* USER CODE END TIM2_Init 0 */
TIM_ClockConfigTypeDef sClockSourceConfig = {0};
TIM_MasterConfigTypeDef sMasterConfig = {0};
TIM_OC_InitTypeDef sConfigOC = {0};
/* USER CODE BEGIN TIM2_Init 1 */
/* USER CODE END TIM2_Init 1 */
htim2.Instance = TIM2;
htim2.Init.Prescaler = 64-1;
htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
htim2.Init.Period = 10000-1;
htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
if (HAL_TIM_Base_Init(&htim2) != HAL_OK)
{
Error_Handler();
}
sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
if (HAL_TIM_ConfigClockSource(&htim2, &sClockSourceConfig) != HAL_OK)
{
Error_Handler();
}
if (HAL_TIM_PWM_Init(&htim2) != HAL_OK)
{
Error_Handler();
}
sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
{
Error_Handler();
}
sConfigOC.OCMode = TIM_OCMODE_PWM1;
sConfigOC.Pulse = 0;
sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
if (HAL_TIM_PWM_ConfigChannel(&htim2, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN TIM2_Init 2 */
/* USER CODE END TIM2_Init 2 */
HAL_TIM_MspPostInit(&htim2);
}TIM_Base_MspInit:
void HAL_TIM_Base_MspInit(TIM_HandleTypeDef* htim_base)
{
if(htim_base->Instance==TIM2)
{
/* USER CODE BEGIN TIM2_MspInit 0 */
/* USER CODE END TIM2_MspInit 0 */
/* Peripheral clock enable */
__HAL_RCC_TIM2_CLK_ENABLE();
/* TIM2 DMA Init */
/* TIM2_CH1 Init */
hdma_tim2_ch1.Instance = DMA1_Channel1;
hdma_tim2_ch1.Init.Request = DMA_REQUEST_TIM2_CH1;
hdma_tim2_ch1.Init.Direction = DMA_MEMORY_TO_PERIPH;
hdma_tim2_ch1.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_tim2_ch1.Init.MemInc = DMA_MINC_ENABLE;
hdma_tim2_ch1.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
hdma_tim2_ch1.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
hdma_tim2_ch1.Init.Mode = DMA_NORMAL;
hdma_tim2_ch1.Init.Priority = DMA_PRIORITY_LOW;
if (HAL_DMA_Init(&hdma_tim2_ch1) != HAL_OK)
{
Error_Handler();
}
__HAL_LINKDMA(htim_base,hdma[TIM_DMA_ID_CC1],hdma_tim2_ch1);
/* USER CODE BEGIN TIM2_MspInit 1 */
/* USER CODE END TIM2_MspInit 1 */
}
}TIM MspPostInit:
void HAL_TIM_MspPostInit(TIM_HandleTypeDef* htim)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
if(htim->Instance==TIM2)
{
/* USER CODE BEGIN TIM2_MspPostInit 0 */
/* USER CODE END TIM2_MspPostInit 0 */
__HAL_RCC_GPIOA_CLK_ENABLE();
/**TIM2 GPIO Configuration
PA0 ------> TIM2_CH1
*/
GPIO_InitStruct.Pin = GPIO_PIN_0;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.Alternate = GPIO_AF1_TIM2;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
/* USER CODE BEGIN TIM2_MspPostInit 1 */
/* USER CODE END TIM2_MspPostInit 1 */
}
}DMA init:
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);
}Code to generate PWM:
int datasentflag=0;
void HAL_TIM_PWM_PulseFinishedCallback(TIM_HandleTypeDef *htim)
{
HAL_TIM_PWM_Stop_DMA(htim, TIM_CHANNEL_1);
datasentflag = 1;
}
uint16_t pwmData[24];
void WS2812_Send (uint32_t color)
{
for (int i=23; i>=0; i--)
{
if (color&(1<<i))
{
pwmData[i] = 6600;
}
else pwmData[i] = 3300;
}
HAL_TIM_PWM_Start_DMA(&htim2, TIM_CHANNEL_1, (uint32_t *)pwmData, 24);
while (!datasentflag){};
datasentflag = 0;
}Main:
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();
/* Configure the peripherals common clocks */
PeriphCommonClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_DMA_Init();
MX_TIM2_Init();
/* USER CODE BEGIN 2 */
uint32_t colour = 0x347235; // colour code for some color
WS2812_Send(colour);
while (1)
{
}
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
/* USER CODE END 3 */
}and this is result on pin PA0 (TIM2_Ch1):
