TIM8四通道无法输出PWM，问题已解决

21创造欲 · 发表于 2019-8-13 18:02:03

TIM8无法输出PWM，软硬件因素很多，这里可以借鉴我的代码查看自己的原因，此程序已经验证成功

//PWM输出初始化
//arr：自动重装值
//psc：时钟预分频数
void TIM8_PWM_Init(u16 arr,u16 psc)
{
   GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
TIM_OCInitTypeDef  TIM_OCInitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8, ENABLE);//
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC , ENABLE);  //使能GPIO外设时钟使能

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7|GPIO_Pin_8|GPIO_Pin_9; //TIM8_CH1-4
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  //复用推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOC, &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(TIM8, &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_OCIdleState = TIM_OCIdleState_Reset ;
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_OC1Init(TIM8, &TIM_OCInitStructure);  //根据TIM_OCInitStruct中指定的参数初始化外设TIMx
TIM_OC1PreloadConfig(TIM8, TIM_OCPreload_Enable);  //CH1预装载使能

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_OCIdleState = TIM_OCIdleState_Reset ;
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(TIM8, &TIM_OCInitStructure);  //根据TIM_OCInitStruct中指定的参数初始化外设TIMx
TIM_OC2PreloadConfig(TIM8, TIM_OCPreload_Enable);  //CH2预装载使能

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_OCIdleState = TIM_OCIdleState_Reset ;
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_OC3Init(TIM8, &TIM_OCInitStructure);  //根据TIM_OCInitStruct中指定的参数初始化外设TIMx
TIM_OC3PreloadConfig(TIM8, TIM_OCPreload_Enable);  //CH3预装载使能

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_OCIdleState = TIM_OCIdleState_Reset ;
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_OC4Init(TIM8, &TIM_OCInitStructure);  //根据TIM_OCInitStruct中指定的参数初始化外设TIMx
TIM_OC4PreloadConfig(TIM8, TIM_OCPreload_Enable);  //CH4预装载使能

TIM_ARRPreloadConfig(TIM8, ENABLE); //使能TIMx在ARR上的预装载寄存器

TIM_Cmd(TIM8, ENABLE);  //使能TIM1
TIM_CtrlPWMOutputs(TIM8,ENABLE); //MOE 主输出使能

}