使用TIM8输出PWM的疑惑

南帝 · 发表于 2014-7-7 12:58:06

我的PWM初始化配置
基本上把官网的例子弄下来的。
TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Disable;
TIM_OCInitStructure.TIM_Pulse = 100;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; // ????
//TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
// TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Set;

TIM_OCInitStructure.TIM_Pulse = 100;
TIM_OC2Init(PWM_TIMX,&TIM_OCInitStructure);
TIM_OCInitStructure.TIM_Pulse = 100;
TIM_OC3Init(PWM_TIMX,&TIM_OCInitStructure);
TIM_OCInitStructure.TIM_Pulse = 100;
TIM_OC4Init(PWM_TIMX,&TIM_OCInitStructure);
TIM_OC1Init(PWM_TIMX,&TIM_OCInitStructure);

我如上配置，输出的PWM CH1 没有信号输出，
CH2 CH3 CH4 都有，
IO设置的模式都是一样的使用的 AF_PP

很奇怪就是没有。
求解啊！