参照野火的程序实现PWM波输出，TIM3的定时没有问题，但是依样画葫芦将程序改写成TIM8则无法输出PWM波。我所做的更改是将GPIO配置中APB1改为APB2,由PA口改为PC6,7,8,9，在配置定时器最后的时候增加了TIM_CtrlPWMOutputs(TIM8 ,ENABLE );
其余没有变动。
如果有任何建议都感激不尽，附文本代码与代码截图。

void TIM8_GPIO_Config(void)
{
        GPIO_InitTypeDef GPIO_InitStructure;

        /* ÉèÖÃTIM8CLK Ϊ 72MHZ */
        RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8, ENABLE);

        /* GPIOC clock enable */
        RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, ENABLE);

        /*GPIOC Configuration: TIM8 channel 1 and 2 as alternate function push-pull */
        GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_6 | GPIO_Pin_7 | GPIO_Pin_8 | GPIO_Pin_9;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;                    // ¸´ÓÃÍÆÍìÊä³ö
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_Init(GPIOC, &GPIO_InitStructure);
}

/**
  * @brief  ÅäÖÃTIM8Êä³öµÄPWMÐźŵÄģʽ£¬ÈçÖÜÆÚ¡¢¼«ÐÔ¡¢Õ¼¿Õ±È
  * @param  ÎÞ
  * @retval ÎÞ
  */
/*
* TIMxCLK/CK_PSC --> TIMxCNT --> TIMx_ARR --> TIMxCNT ÖØмÆÊý
*                    TIMx_CCR(µçƽ·¢Éú±ä»¯)
* ÐźÅÖÜÆÚ=(TIMx_ARR +1 ) * ʱÖÓÖÜÆÚ
* Õ¼¿Õ±È=TIMx_CCR/(TIMx_ARR +1)
*/
void TIM8_Mode_Config(void)
{
        TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
        TIM_OCInitTypeDef  TIM_OCInitStructure;
        
        //TIM_DeInit(TIM8); //
        
        /* PWMÐźŵçƽÌø±äÖµ */
         u16 CCR1_Val = 500;        
         u16 CCR2_Val = 375;
         u16 CCR3_Val = 250;
         u16 CCR4_Val = 125;

/* -----------------------------------------------------------------------
    TIM8 Channel1 duty cycle = (TIM3_CCR1/ TIM3_ARR+1)* 100% = 50%
    TIM8 Channel2 duty cycle = (TIM3_CCR2/ TIM3_ARR+1)* 100% = 37.5%
    TIM8 Channel3 duty cycle = (TIM3_CCR3/ TIM3_ARR+1)* 100% = 25%
    TIM8 Channel4 duty cycle = (TIM3_CCR4/ TIM3_ARR+1)* 100% = 12.5%
  ----------------------------------------------------------------------- */

        /* Time base configuration */                 
        TIM_TimeBaseStructure.TIM_Period = 999;       //µ±¶¨Ê±Æ÷´Ó0¼ÆÊýµ½999£¬¼´Îª1000´Î£¬ÎªÒ»¸ö¶¨Ê±ÖÜÆÚ
        TIM_TimeBaseStructure.TIM_Prescaler = 1800;            //ÉèÖÃÔ¤·ÖƵ£º1800·ÖƵ£¬¼´Îª40KHz
        TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1 ;        //ÉèÖÃʱÖÓ·ÖƵϵÊý£º²»·ÖƵ(ÕâÀïÓò»µ½)
        TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //ÏòÉϼÆÊýģʽ
        TIM_TimeBaseStructure.TIM_RepetitionCounter = 0x0;
        TIM_TimeBaseInit(TIM8, &TIM_TimeBaseStructure);

        /* PWM1 Mode configuration: Channel1 */
        TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;            //ÅäÖÃΪPWMģʽ1
        TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
        TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;        
        TIM_OCInitStructure.TIM_Pulse = CCR1_Val;           //ÉèÖÃÌø±äÖµ£¬µ±¼ÆÊýÆ÷¼ÆÊýµ½Õâ¸öֵʱ£¬µçƽ·¢ÉúÌø±ä
        TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;  //µ±¶¨Ê±Æ÷¼ÆÊýֵСÓÚCCR1_ValʱΪ¸ßµçƽ
        TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
        TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
        TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;
        TIM_OC1Init(TIM8, &TIM_OCInitStructure);         //ʹÄÜͨµÀ1
        TIM_OC1PreloadConfig(TIM8, TIM_OCPreload_Enable);

        /* PWM1 Mode configuration: Channel2 */
        TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
        TIM_OCInitStructure.TIM_Pulse = CCR2_Val;          //ÉèÖÃͨµÀ2µÄµçƽÌø±äÖµ£¬Êä³öÁíÍâÒ»¸öÕ¼¿Õ±ÈµÄPWM
        TIM_OC2Init(TIM8, &TIM_OCInitStructure);          //ʹÄÜͨµÀ2
        TIM_OC2PreloadConfig(TIM8, TIM_OCPreload_Enable);

        /* PWM1 Mode configuration: Channel3 */
        TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
        TIM_OCInitStructure.TIM_Pulse = CCR3_Val;        //ÉèÖÃͨµÀ3µÄµçƽÌø±äÖµ£¬Êä³öÁíÍâÒ»¸öÕ¼¿Õ±ÈµÄPWM
        TIM_OC3Init(TIM8, &TIM_OCInitStructure);         //ʹÄÜͨµÀ3
        TIM_OC3PreloadConfig(TIM8, TIM_OCPreload_Enable);

        /* PWM1 Mode configuration: Channel4 */
        TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
        TIM_OCInitStructure.TIM_Pulse = CCR4_Val;        //ÉèÖÃͨµÀ4µÄµçƽÌø±äÖµ£¬Êä³öÁíÍâÒ»¸öÕ¼¿Õ±ÈµÄPWM
        TIM_OC4Init(TIM8, &TIM_OCInitStructure);        //ʹÄÜͨµÀ4
        TIM_OC4PreloadConfig(TIM8, TIM_OCPreload_Enable);
        TIM_ARRPreloadConfig(TIM8, ENABLE);                         // ʹÄÜTIM3ÖØÔؼĴæÆ÷ARR

        /* TIM3 enable counter */
        TIM_Cmd(TIM8, ENABLE);                   //ʹÄܶ¨Ê±Æ÷8
        TIM_CtrlPWMOutputs(TIM8 ,ENABLE );

谢谢楼主分享

JackieLaura 发表于 2015-9-7 23:43
谢谢楼主分享

这个方法不错，每次多赚一分

风子 发表于 2015-9-7 23:49
这个方法不错，每次多赚一分

这个也是借鉴别人的

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