STM32F4 TIM4配置问题.....

CCSYJQ · 发表于 2022-1-22 16:39:12

大佬们帮我看看这个tim4配置输出不了40K  输出什么都没有
void TIM4_PWM_Init(u32 arr,u32 psc)
{
//此部分需手动修改IO口设置

GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
TIM_OCInitTypeDef  TIM_OCInitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4,ENABLE);    //TIM4时钟使能
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE); //使能PORTF时钟

GPIO_PinAFConfig(GPIOB,GPIO_PinSource8,GPIO_AF_TIM4); //GPIO复用为定时器4

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;          //GPIOF9
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(GPIOB,&GPIO_InitStructure);             //初始化PF9

TIM_TimeBaseStructure.TIM_Prescaler=84-1;  //定时器分频
TIM_TimeBaseStructure.TIM_CounterMode=TIM_CounterMode_Up; //向上计数模式
TIM_TimeBaseStructure.TIM_Period=25-1; //自动重装载值
TIM_TimeBaseStructure.TIM_ClockDivision=TIM_CKD_DIV1;
TIM_TimeBaseInit(TIM4,&TIM_TimeBaseStructure);//初始化定时器4

//初始化TIM4 Channel3 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2
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输出比较极性低
TIM_OC3Init(TIM4, &TIM_OCInitStructure);  //根据T指定的参数初始化外设TIM1 4OC1

TIM_OC3PreloadConfig(TIM4, TIM_OCPreload_Enable);  //使能TIM4在CCR1上的预装载寄存器

  TIM_ARRPreloadConfig(TIM4,ENABLE);//ARPE使能

TIM_Cmd(TIM4, ENABLE);  //使能TIM4
TIM_CtrlPWMOutputs(TIM4,ENABLE);                      //使能TIM1的PWM输出

}