F407定时器 period（周期）为0，中断服务函数不执行

qq807665216 · 发表于 2021-6-3 08:45:51

本帖最后由 qq807665216 于 2021-6-3 09:41 编辑

F407定时器 period（周期）为0，中断服务函数不执行。

void TIM8_PWM_Init(u32 arr,u32 psc) // 定时器8初始化函数
{
//此部分需手动修改IO口设置
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM8,ENABLE); //TIM8时钟使能
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE); //使能GPIOC时钟
GPIO_PinAFConfig(GPIOC,GPIO_PinSource6,GPIO_AF_TIM8); //GPIOC6复用为定时器8 OC1
GPIO_PinAFConfig(GPIOC,GPIO_PinSource7,GPIO_AF_TIM8); //GPIOC7复用为定时器8 OC2
GPIO_PinAFConfig(GPIOC,GPIO_PinSource8,GPIO_AF_TIM8); //GPIOC8复用为定时器8 OC3
GPIO_PinAFConfig(GPIOC,GPIO_PinSource9,GPIO_AF_TIM8); //GPIOC9复用为定时器8 OC4
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7|GPIO_Pin_8|GPIO_Pin_9; // GPIOC6/7/8/9
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; //复用功能
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz; //速度100MHz
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //推挽复用输出
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; //上拉
GPIO_Init(GPIOC,&GPIO_InitStructure); //初始化PC6 7 8 9
TIM_TimeBaseStructure.TIM_Prescaler=psc; //定时器分频
TIM_TimeBaseStructure.TIM_CounterMode=TIM_CounterMode_Up; //向上计数模式
TIM_TimeBaseStructure.TIM_Period=arr; //自动重装载值
TIM_TimeBaseStructure.TIM_ClockDivision=TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_RepetitionCounter = 0; //重复计数器
TIM_TimeBaseInit(TIM8,&TIM_TimeBaseStructure);//初始化定时器8
//初始化TIM8 Channel PWM模式
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //选择定时器模式:TIM脉冲宽度调制模式1
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高
TIM_OCInitStructure.TIM_Pulse = 0;
TIM_OC1Init(TIM8, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM8
TIM_OC1PreloadConfig(TIM8, TIM_OCPreload_Enable); //使能TIM8在CCR1上的预装载寄存器
TIM_CtrlPWMOutputs(TIM8, ENABLE);
TIM_OC2Init(TIM8, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM8
TIM_OC2PreloadConfig(TIM8, TIM_OCPreload_Enable); //使能TIM8在CCR1上的预装载寄存器
TIM_CtrlPWMOutputs(TIM8, ENABLE);
TIM_OC3Init(TIM8, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM8
TIM_OC3PreloadConfig(TIM8, TIM_OCPreload_Enable); //使能TIM8在CCR1上的预装载寄存器
TIM_CtrlPWMOutputs(TIM8, ENABLE);
TIM_OC4Init(TIM8, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM8
TIM_OC4PreloadConfig(TIM8, TIM_OCPreload_Enable); //使能TIM8在CCR1上的预装载寄存器
TIM_CtrlPWMOutputs(TIM8, ENABLE);
　　 TIM_ARRPreloadConfig(TIM8,ENABLE); //ARPE使能
TIM_SelectMasterSlaveMode(TIM8, TIM_MasterSlaveMode_Enable); //主从模式使能
　　 TIM_SelectOutputTrigger(TIM8, TIM_TRGOSource_Update); //更新时间为触发输出
TIM_ITConfig(TIM8,TIM_IT_Update,ENABLE); //允许定时器8更新中断
NVIC_InitStructure.NVIC_IRQChannel=TIM8_UP_TIM13_IRQn; //定时器8中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=0x05; //抢占优先级5
NVIC_InitStructure.NVIC_IRQChannelSubPriority=0x00; //子优先级0
NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;
NVIC_Init(&NVIC_InitStructure);
TIM_Cmd(TIM8,ENABLE); //使能定时器8
}

复制代码

void TIM4_config(u32 PulseNum)//定时器4初始化函数
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);
TIM_TimeBaseStructure.TIM_Period = PulseNum-1; //定时器4的周期
TIM_TimeBaseStructure.TIM_Prescaler =0; //预分频系数（不分频）
TIM_TimeBaseStructure.TIM_ClockDivision = 0; //
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //向上计数模式
TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure); //初始化TIM4
TIM_SelectMasterSlaveMode(TIM4, TIM_MasterSlaveMode_Enable); //设置主从模式
TIM_SelectSlaveMode(TIM4,TIM_SlaveMode_External1); //TIM_SlaveMode_External1:所选触发器(TRGI)时钟计数器的上升边缘
TIM_SelectInputTrigger(TIM4, TIM_TS_ITR3); //选择输入触发器源
TIM_ITRxExternalClockConfig(TIM4,TIM_TS_ITR3);
TIM_ARRPreloadConfig(TIM4,DISABLE);
TIM_ITConfig(TIM4,TIM_IT_Update,ENABLE); //使能TIM4的update中断
NVIC_InitStructure.NVIC_IRQChannel = TIM4_IRQn; //选择定时器4中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x05; //抢占优先级为5
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0; //响应优先级为0
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //使能定时器4中断
NVIC_Init(&NVIC_InitStructure); //定时器4中断初始化
TIM_Cmd(TIM4,ENABLE); //使能定时器4
}

复制代码

主要的功能是：TIM8作为主定时器输出PWM波，TIM4作为从定时器为主定时器(TIM8)计数
使用的是FreeRTOS，在TIM4触发中断后，TIM4的中断服务函数发送二值信号量，任务接收到二值信号量对TIM8的ARR和CCR１寄存器、TIM４的ARR寄存器重新赋值
达到输出一定数量的PWM波的效果
问题：如果计数一个PWM波，需要将TIM4的ARR赋0（赋1的话是计算2个PWM波），如果将ARR赋0的话，TIM４的中断没有被执行