我的板小不能放晶振用的是内部时钟，用示波器看过可以工作的，采用的是硬石的风格。用TIM3,14,15,17都试过都有脉冲输出。

初始化PWM后
HAL_TIM_PWM_Start(&htimx,TIM_CHANNEL_2);
打开PWM，示波器上就有波形输出，不能关！

  user_pwm_setvalue(0);  用这个关，实际上PWM没关给它低电平。

PWM关就再也打不开了

/**,我只是路过打酱油的，嘿嘿

LIUBEIHUA 发表于 2017-4-26 16:22
初始化PWM后
HAL_TIM_PWM_Start(&htimx,TIM_CHANNEL_2);
打开PWM，示波器上就有波形输出，不能关！

谢谢你的热心回复用这个函数关也是有延迟
HAL_TIM_PWM_Start(&htimx,TIM_CHANNEL_2);
HAL_TIM_PWM_Stop(&htimx,TIM_CHANNEL_2);



user_pwm_setvalue(0);  用这个关掉再打开PWM
关是关了，情况没改善，跟我用寄存器的方式是一样的问题
比如我只要关1ms
实际会关5.6ms

另外我也是内部晶振

来学习下

中午吃饭休息时间做的红外发射程序

/**
  ******************************************************************************
  * File Name          : main.c
  * Description        : Main program body
  ******************************************************************************
  *
  * COPYRIGHT(c) 2017 STMicroelectronics
  *
  * Redistribution and use in source and binary forms, with or without modification,
  * are permitted provided that the following conditions are met:
  *   1. Redistributions of source code must retain the above copyright notice,
  *      this list of conditions and the following disclaimer.
  *   2. Redistributions in binary form must reproduce the above copyright notice,
  *      this list of conditions and the following disclaimer in the documentation
  *      and/or other materials provided with the distribution.
  *   3. Neither the name of STMicroelectronics nor the names of its contributors
  *      may be used to endorse or promote products derived from this software
  *      without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  ******************************************************************************
  */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "stm32f0xx_hal.h"

uint8_t keyfg;
uint8_t sendfg;
uint8_t button;
uint8_t controlcode[2];
uint8_t compensate;
uint8_t User_code[3]={0x86, 0x79};

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

/* USER CODE BEGIN PV */
/* Private variables ---------------------------------------------------------*/

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
void Error_Handler(void);
static void MX_GPIO_Init(void);
static void MX_TIM3_Init(void);                                    
void HAL_TIM_MspPostInit(TIM_HandleTypeDef *htim);

void user_pwm_setvalue(uint16_t value)
{
    TIM_OC_InitTypeDef sConfigOC;
  
    sConfigOC.OCMode = TIM_OCMODE_PWM1;
    sConfigOC.Pulse = value;
    sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
    sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
    HAL_TIM_PWM_ConfigChannel(&htim3, &sConfigOC, TIM_CHANNEL_2);
    HAL_TIM_PWM_Start(&htim3, TIM_CHANNEL_2);  
}

void Bit0_Encode_SignalGenerate(void)
{
        user_pwm_setvalue(316);
        HAL_Delay(56);
        user_pwm_setvalue(0);
        HAL_Delay(56);
}

void Bit1_Encode_SignalGenerate(void)
{
        user_pwm_setvalue(316);
        HAL_Delay(56);
        user_pwm_setvalue(0);
        HAL_Delay(168);
}

void Head_Encode_SignalGenerate(void)
{
        user_pwm_setvalue(316);
        HAL_Delay(900);
        user_pwm_setvalue(0);
        HAL_Delay(450);
}

void End_Encode_SignalGenerate(void)
{
        user_pwm_setvalue(316);
        HAL_Delay(56);
        user_pwm_setvalue(0);
        HAL_Delay(56);
        user_pwm_setvalue(316);
        HAL_Delay(56);
        user_pwm_setvalue(0);
}

void Encode_SignalGenerate(uint8_t * dat)
{
        uint8_t usercode[2];
        uint8_t i, j;
        usercode[0]=dat[0];
        usercode[1]=dat[1];
        for(j=0; j<2; j++)
        {
                for(i=0; i<8; i++)
                {
                        if(usercode[j]&0x80)
                                Bit1_Encode_SignalGenerate();
                        else
                                Bit0_Encode_SignalGenerate();
                        usercode[j]=usercode[j]<<1;
                }
        }
}

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();

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

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_TIM3_Init();

  /* 启动通道PWM输出 */
  HAL_TIM_PWM_Start(&htim3,TIM_CHANNEL_2);
  user_pwm_setvalue(0);

  controlcode[0]=0xd2;
  controlcode[0]=0x2d;
  while (1)
  {
         Head_Encode_SignalGenerate();
         Encode_SignalGenerate(User_code);
         Encode_SignalGenerate(controlcode);
         End_Encode_SignalGenerate();
         HAL_Delay(4200);
  }

}

/** System Clock Configuration
*/
void SystemClock_Config(void)
{

  RCC_OscInitTypeDef RCC_OscInitStruct;
  RCC_ClkInitTypeDef RCC_ClkInitStruct;

    /**Initializes the CPU, AHB and APB busses clocks
    */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  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_MUL6;
  RCC_OscInitStruct.PLL.PREDIV = RCC_PREDIV_DIV1;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

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

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK)
  {
    Error_Handler();
  }

    /**Configure the Systick interrupt time
    */
  HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/100000);

    /**Configure the Systick
    */
  HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);

  /* SysTick_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}

/* TIM3 init function */
static void MX_TIM3_Init(void)
{

  TIM_ClockConfigTypeDef sClockSourceConfig;
  TIM_MasterConfigTypeDef sMasterConfig;
  TIM_OC_InitTypeDef sConfigOC;

  htim3.Instance = TIM3;
  htim3.Init.Prescaler = 0;
  htim3.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim3.Init.Period = 1266;
  htim3.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  htim3.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
  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 = 633;
  sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
  sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
  if (HAL_TIM_PWM_ConfigChannel(&htim3, &sConfigOC, TIM_CHANNEL_2) != HAL_OK)
  {
    Error_Handler();
  }

  HAL_TIM_MspPostInit(&htim3);

}

/** Configure pins as
        * Analog
        * Input
        * Output
        * EVENT_OUT
        * EXTI
*/
static void MX_GPIO_Init(void)
{

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

}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

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

#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

/**
  * @}
  */

/**
  * @}
*/

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

/**Configure the Systick interrupt time
    */
  HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/100000); //此处100000 这样HAL_Delay()变成10us

    /**Configure the Systick
HAL_Delay(56);就是560us

完整的程序

LIUBEIHUA 发表于 2017-4-27 13:02
完整的程序

非常感谢您的热心回复。
今天下午改用GPIO脚加三极管来开关红外发射，PWM则一直输出38K方波
发现个奇葩的现象：
用GPIO控制一样有延迟问题，而且延迟的时间也是一样。
看来这不是PWM的问题
我把while大循环的所有程序屏蔽掉，只留红外发射，就没有延迟
如果加上
HAL_Delay(10);//10ms
也没延迟，改到15ms以上就有有延迟了。。。
这个问题搞了几天，我快抓狂了。。。

我看了一下我的中断，中断里面没加什么耗时的程序，都是只有一点点简单的减法。为了省时间我连回调函数都关掉了........




最后，发现是发送红外信号时，板子上的红外接收头收到了刚发送的信号，（板子有发送也有接收）进入了接收中断。然后就不用说了。。。。。

非常感谢您的热心回复。