PWM输不出来，帮忙看下定时器TIM1初始化没有没问题？？谢谢

亮亮 · 发表于 2015-2-5 22:32:47

void PWM_Init(u16 arr,u16 psc)
{

GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);

//设置该引脚为复用输出功能,输出TIM1 CH2的PWM脉冲波形

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8|GPIO_Pin_9|GPIO_Pin_10|GPIO_Pin_11; //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_TimeBaseStructure.TIM_Period = arr; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值 80K
TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值不分频
TIM_TimeBaseStructure.TIM_ClockDivision = 0; //设置时钟分割:TDTS = Tck_tim
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位

TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2; //选择定时器模式:TIM脉冲宽度调制模式2
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_Pulse = 0; //设置待装入捕获比较寄存器的脉冲值
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高

TIM_OC2Init(TIM1, &TIM_OCInitStructure); //根据TIM_OCInitStruct中指定的参数初始化外设TIMx
TIM_OC1Init(TIM1, &TIM_OCInitStructure);
TIM_OC3Init(TIM1, &TIM_OCInitStructure);
TIM_OC4Init(TIM1, &TIM_OCInitStructure);

TIM_OC2PreloadConfig(TIM1, TIM_OCPreload_Enable); //使能TIMx在CCR2上的预装载寄存器
TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);
TIM_OC3PreloadConfig(TIM1, TIM_OCPreload_Enable);
TIM_OC4PreloadConfig(TIM1, TIM_OCPreload_Enable);

TIM_ARRPreloadConfig(TIM1, ENABLE); //使能TIMx在ARR上的预装载寄存器

TIM_Cmd(TIM1, ENABLE); //使能TIMx外设
TIM_CtrlPWMOutputs(TIM1, ENABLE); //设置PMW主输出

}