原子哥，请教一下TIM_OCPolarity的问题

liming1111114

我想让TIM1输出PWM波，但是改变 TIM_OCPolarity 等于Low或High时波形没有变化啊，请问原子哥这是为什么啊？理论上TIM_OCPolarity改变后波形应该是颠倒过来的啊

void PWM_TimeBase( TIM_TypeDef* PWM_TIMx , u16 PWM_Period , u16 PWM_Prescaler )

{

TIM_TimeBaseInitTypeDef PWM_TimeBaseStructure;

TIM_DeInit(PWM_TIMx);

PWM_TimeBaseStructure.TIM_Period=PWM_Period;

PWM_TimeBaseStructure.TIM_Prescaler=PWM_Prescaler; 

PWM_TimeBaseStructure.TIM_ClockDivision=TIM_CKD_DIV1;

  PWM_TimeBaseStructure.TIM_CounterMode=TIM_CounterMode_Up;

//PWM_TimeBaseStructure.TIM_RepetitionCounter = 0; 

TIM_TimeBaseInit(PWM_TIMx,&WM_TimeBaseStructure);

}

/* Motor Control */

void Motor_InitConf(void)

{

/*******************************************************************************/

    TIM_OCInitTypeDef TIM_OCInitStructure;                        

PWM_TimeBase(TIM1,1000-1,0);

/* Mode config */

    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;               

TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;      

    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;  

/* TIM1_Channel_1,2 Config */

TIM_OCInitStructure.TIM_Pulse = 800;

TIM_OC1Init(TIM1,&TIM_OCInitStructure);

TIM_OC1PreloadConfig(TIM1,TIM_OCPreload_Enable);

TIM_OCInitStructure.TIM_Pulse = 200;

TIM_OC2Init(TIM1,&TIM_OCInitStructure);

TIM_OC2PreloadConfig(TIM1,TIM_OCPreload_Enable);

TIM_ARRPreloadConfig(TIM1,ENABLE);                              

  

    TIM_Cmd(TIM1, ENABLE);           

                              

    TIM_CtrlPWMOutputs(TIM1, ENABLE);                              

}

正点原子

回复【楼主位】 liming1111114 :

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我不用库函数,但是寄存器关于这个有过讨论,你看看这个帖子:http://www.openedv.com/posts/list/140.htm