STM32 通用定时器tim2和tim5调光的亮度差异

王昌阳

为什么自动装载值和分频系数一样的TIM2和TIM5(PWM初始化程序)，用来调整LED的亮度。但为什么LED的亮度相差很大。
/////TIM5

void TIM5_PWM_Init(void)
{
        TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
        TIM_OCInitTypeDef TIM_OCInitStructure;
       
//        RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
        RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5,ENABLE);
       
        TIM_TimeBaseInitStructure.TIM_Period = 255;
        TIM_TimeBaseInitStructure.TIM_Prescaler = 1999;
        TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
        TIM_TimeBaseInitStructure.TIM_CounterMode=TIM_CounterMode_Up; //éèÖÃÏòéϼÆêyÄ￡ê½
        TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStructure);
       
        TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
        TIM_OCInitStructure.TIM_OCPolarity =TIM_OCPolarity_High;
        TIM_OCInitStructure.TIM_Pulse = 0;
        TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
       
        TIM_OC2Init(TIM5,&TIM_OCInitStructure);
        TIM_OC2PreloadConfig(TIM5,TIM_OCPreload_Enable);
       
        TIM_OC3Init(TIM5,&TIM_OCInitStructure);
        TIM_OC3PreloadConfig(TIM5,TIM_OCPreload_Enable);
       
        TIM_OC4Init(TIM5,&TIM_OCInitStructure);
        TIM_OC4PreloadConfig(TIM5,TIM_OCPreload_Enable);
       
        TIM_ARRPreloadConfig(TIM5,ENABLE);
        TIM_Cmd(TIM5, ENABLE);
}



/////TIM2
void TIM2_PWM_Init(void)
{
        TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
        TIM_OCInitTypeDef TIM_OCInitStructure;
       
//        RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
        RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2,ENABLE);
       
        TIM_TimeBaseInitStructure.TIM_Period = 255;
        TIM_TimeBaseInitStructure.TIM_Prescaler = 1999;
        TIM_TimeBaseInitStructure.TIM_ClockDivision = TIM_CKD_DIV1;
        TIM_TimeBaseInitStructure.TIM_CounterMode=TIM_CounterMode_Up;
        TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStructure);
       
        TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
        TIM_OCInitStructure.TIM_OCPolarity =TIM_OCPolarity_High;
        TIM_OCInitStructure.TIM_Pulse = 0;
        TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
       
        TIM_OC2Init(TIM2,&TIM_OCInitStructure);
        TIM_OC2PreloadConfig(TIM2,TIM_OCPreload_Enable); //ê1ÄüTIMxÔú CCR2 éÏμÄԤװÔؼÄ′æÆ÷
       
        TIM_OC3Init(TIM2,&TIM_OCInitStructure);
        TIM_OC3PreloadConfig(TIM2,TIM_OCPreload_Enable);
       
        TIM_OC4Init(TIM2,&TIM_OCInitStructure);
        TIM_OC4PreloadConfig(TIM2,TIM_OCPreload_Enable);
       
        TIM_ARRPreloadConfig(TIM2,ENABLE);
        TIM_Cmd(TIM2, ENABLE);
}

王昌阳

问题再找到了。TIM5的  TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStructure);没改成TIM5      

翼行园子

示波器读下波形 看看占空比是不是一样的