STM32F103C8T6为什么通过PB0无法输出PWM

方正波 · 发表于 2022-10-10 16:34:37

本帖最后由方正波于 2022-10-10 16:37 编辑

看技术手册可以用TIM3 通道3 直接输出，都不需要复用啊，理论上应该通过示波器可以抓到脉冲啦，但是我测量没有输出。

int main(void)
{
TIM3_PWM_Init(4999,7199);    //500ms
while (1)
{

}
}

//TIM3 PWM部分初始化
//PWM输出初始化
//arr：自动重装值
//psc：时钟预分频数
void TIM3_PWM_Init(u16 arr,u16 psc)
{

GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
TIM_OCInitTypeDef  TIM_OCInitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //使能定时器3时钟

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB , ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; //TIM3_CH3
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_OD;  //复用推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);//初始化GPIO

//初始化TIM3
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
TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值
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(TIM3, &TIM_TimeBaseStructure);

TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High
TIM_OC3Init(TIM3, &TIM_OCInitStructure);

TIM_OC3PreloadConfig(TIM3, TIM_OCPreload_Enable);

TIM_Cmd(TIM3, ENABLE);

}