STM32F103C8 重上电 PWM不输出

Oyster 回答时间：2018-9-5 10:37:06

如题：配置的是TIM1的CH1（PA8）用来控制舵机的下载完程序和重新上电后其他程序都可以正常跑但是就是重新上电后PA8就没有PWM了，下载完程序跑是有的，看到有说修改硬件初始化顺序的，但是没有成功。最后贴上这部分的代码，有知道的请指教，不胜感激！
//定时器初始化配置函数
//psc 定时器分频系数
//per 重装载值
void Tim1_Configuration(uint16_t psc,uint16_t per)
{
      GPIO_InitTypeDef GPIO_InitStructure;
      TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
      TIM_OCInitTypeDef  TIM_OCInitStructure;

      RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);             //定时器1时钟打开

      RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA , ENABLE);  //使能GPIO外设时钟使能

//设置该引脚为复用输出功能,输出TIM1 CH1的PWM脉冲波形
      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8; //TIM_CH1
      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  //复用推挽输出
      GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
      GPIO_Init(GPIOA, &GPIO_InitStructure);
      TIM_DeInit(TIM1);                                                                                     //外设 TIMx 寄存器重设为缺省值

      TIM_TimeBaseStructure.TIM_Period = per-1;                            //计数周期
      TIM_TimeBaseStructure.TIM_Prescaler = psc-1;                                  //设置预分频从APB2-->72M
      TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1 ;       //设置时钟分频系数：不分频(这里用不到)
      TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;       //向上计数模式
      TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);

      //PWM1 Mode configuration
      TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;                   //配置为PWM模式1
      TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;       //比较输出使能
      TIM_OCInitStructure.TIM_Pulse = 0;                                                          //设置跳变值，当计数器计数到这个值时，电平发生跳变
      TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;       //当定时器计数值小于CCR1_Val时为高电平


      TIM_OC1Init(TIM1, &TIM_OCInitStructure);                      //使能通道1
      TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);       //通道1重装载使能

      TIM_CtrlPWMOutputs(TIM1,ENABLE);                                     //使能定时器1 PWM
      TIM_ARRPreloadConfig(TIM1, ENABLE);                                        //使能TIM1重载寄存器ARR

      TIM_Cmd(TIM1, ENABLE);                                        //使能定时器1
}

void Pwm_Configuration(void)
{
      Tim1_Configuration(72,20000);       //1us*20000 20ms  50Hz频率

      Tim4_Configuration(36,1000);       //1us*1000  1ms 1Khz频率

｝

下面是TIM4的应该没什么影响，也贴上
//定时器初始化配置函数
//psc 定时器分频系数
//per 重装载值
void Tim4_Configuration(uint16_t psc,uint16_t per)
{
      GPIO_InitTypeDef GPIO_InitStructure;
      TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
      TIM_OCInitTypeDef  TIM_OCInitStructure;

      RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);

      RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);

      GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_8 | GPIO_Pin_9;
      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;                   // 复用推挽输出
      GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
      GPIO_Init(GPIOB, &GPIO_InitStructure);

      TIM_DeInit(TIM4);                                                                                     //外设 TIMx 寄存器重设为缺省值

      TIM_TimeBaseStructure.TIM_Period = per-1;                            //计数周期
      TIM_TimeBaseStructure.TIM_Prescaler = psc-1;                                  //设置预分频从APB1-->36M
      TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1 ;       //设置时钟分频系数：不分频(这里用不到)
      TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;       //向上计数模式
      TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure);

      //PWM1 Mode configuration
      TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;                   //配置为PWM模式1
      TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
      TIM_OCInitStructure.TIM_Pulse = 0;                                                          //设置跳变值，当计数器计数到这个值时，电平发生跳变
      TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;       //当定时器计数值小于CCR1_Val时为高电平

      //Channel3
      TIM_OC3Init(TIM4, &TIM_OCInitStructure);                      //使能通道3
      TIM_OC3PreloadConfig(TIM4, TIM_OCPreload_Enable);       //通道3重装载使能

      //Channel4
      TIM_OC4Init(TIM4, &TIM_OCInitStructure);                      //使能通道4
      TIM_OC4PreloadConfig(TIM4, TIM_OCPreload_Enable);       //通道4重装载使能

      TIM_ARRPreloadConfig(TIM4, ENABLE);                                        //使能TIM4重载寄存器ARR

      TIM_Cmd(TIM4, ENABLE);                                        //使能定时器4
}