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我想使用 stm32 生成 PWM 信号，但我必须能够在每个信号后更改占空比。我的问题是，如果我尝试它不能正常工作。它以相同的占空比发送 3-5 个脉冲，然后更改值。我不明白为什么它在每次脉冲后都会改变它。还有另一个问题，我必须在每个脉冲之后重新启用通道的 CCER 位，否则它不起作用，它会因任何原因被重置。

我正在使用带有 Keil uVision 5 的 STM32G071 Nucleo-64 板

我用 STM32CubeMX 生成了开头并添加了我的代码，所以它可以工作，但它没有。我不知道该怎么做。我会很高兴得到一些建议。

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
#define HIGH_PWM_SIGNAL     70//( 45 )
#define LOW_PWM_SIGNAL      10//( 27 )

/* USER CODE END PD */

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

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
TIM_HandleTypeDef htim3;

/* USER CODE BEGIN PV */
uint8_t PWM_Count = 0;

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM3_Init(void);
static void MX_NVIC_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 */

  /* 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();

  /* Initialize interrupts */
  MX_NVIC_Init();
  /* USER CODE BEGIN 2 */

    HAL_TIM_Base_Start_IT( &htim3 );
    HAL_TIM_PWM_Start_IT( &htim3, TIM_CHANNEL_1 );

  /* 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)
{
  // STM32CUbeMX generated deleted for readablitity
}

/**
  * @brief NVIC Configuration.
  * @retval None
  */
static void MX_NVIC_Init(void)
{
  /* TIM3_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(TIM3_IRQn, 1, 0);
  HAL_NVIC_EnableIRQ(TIM3_IRQn);
}

/**
  * @brief TIM3 Initialization Function
  * @param None
  * @retval None
  */
static void MX_TIM3_Init(void)
{

  /* USER CODE BEGIN TIM3_Init 0 */
    HAL_TIM_Base_DeInit( &htim3 );
    HAL_TIM_PWM_DeInit( &htim3 );

  /* 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 = 0;
  htim3.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim3.Init.Period = 80;
  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 = 10;
  sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
  sConfigOC.OCFastMode = TIM_OCFAST_ENABLE;
  if (HAL_TIM_PWM_ConfigChannel(&htim3, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN TIM3_Init 2 */
    HAL_NVIC_SetPriority( TIM3_IRQn, 0, 0);
    HAL_NVIC_EnableIRQ( TIM3_IRQn );
    // Update interrupt
    HAL_TIM_GenerateEvent( &htim3, TIM_EVENTSOURCE_UPDATE );
    // PWM interrupt
    HAL_TIM_GenerateEvent( &htim3, TIM_EVENTSOURCE_CC1 );

  /* USER CODE END TIM3_Init 2 */
  HAL_TIM_MspPostInit(&htim3);

}

/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  // STM32CUbeMX generated deleted for readablitity
}

/* USER CODE BEGIN 4 */
void HAL_TIM_PWM_PulseFinishedCallback(TIM_HandleTypeDef *htim){

       // Change PWM Duty Cycle

    PWM_Count += 1;
    if ( PWM_Count > 1 ) 
        PWM_Count = 0;

    if ( PWM_Count == 0 ) TIM3->CCR1  = LOW_PWM_SIGNAL;
    else    TIM3->CCR1  = HIGH_PWM_SIGNAL;

}

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim){ 

   // I have to re enable it or it doesn't output anything

   TIM_CCxChannelCmd(htim3.Instance, TIM_CHANNEL_1, TIM_CCx_ENABLE);


}
/* 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 */

  /* USER CODE END Error_Handler_Debug */
}

它不会改变它需要大约 3-5 个信号的每个信号的占空比，然后它会改变占空比。 示波器：输出 PWM 通道 1

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1 回答 1

1

我找到了解决方案。我使用的是库“stm32g0xx_hal_tim.c”，非常方便。但它用了很多时间。

它适用于所有问题并因此检查所有内容（所有中断标志）。这有很多 if else 需要一些时间。

我自己编写了它，它只检查我需要的东西，然后它就起作用了。

谢谢您的帮助。

于 2019-11-12T12:15:20.290 回答