f103C8 定时器3通道2PWM问题

x962239349

f103C8的代码如下，极性无论改成高还是低，我的两个灯都是一直亮着的，没有呼吸灯效果，我用的是PB8 定时器4通道三，求大佬解答，谢谢！
#include "pwm.h"
#include "sys.h"
#include "led.h"

void TIM4_Int_Init(u16 arr,u16 psc)
{   
    TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStrue;
    NVIC_InitTypeDef NVIC_InitStructture;

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4,ENABLE);

    TIM_TimeBaseInitStrue.TIM_Period = arr;
    TIM_TimeBaseInitStrue.TIM_Prescaler = psc;
    TIM_TimeBaseInitStrue.TIM_CounterMode =TIM_CounterMode_Up;
    TIM_TimeBaseInitStrue.TIM_ClockDivision =0;
    TIM_TimeBaseInit(TIM4,&TIM_TimeBaseInitStrue);  

    TIM_ITConfig(TIM4,TIM_IT_Update,ENABLE);

    NVIC_InitStructture.NVIC_IRQChannel = TIM4_IRQn;
    NVIC_InitStructture.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructture.NVIC_IRQChannelSubPriority = 3;
    NVIC_InitStructture.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructture);

    TIM_Cmd(TIM4,ENABLE);
}

void TIM4_IRQHandler(void)
{
    if(TIM_GetITStatus(TIM4,TIM_IT_Update)!=RESET)
    {
        LED1=!LED1;
        TIM_ClearITPendingBit(TIM4,TIM_IT_Update);
    }
}
void TIM4_PWM_Init(u16 arr,u16 psc)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStrue;
    TIM_OCInitTypeDef TIM_OCInitTypeStrue;

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4,ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB|RCC_APB2Periph_AFIO,ENABLE);

                GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;                                 // ¶Ë¿úÅäÖÃ
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;                  
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;                 //IO¿úËù¶èÎa50MHz
    GPIO_Init(GPIOB, &GPIO_InitStructure);      

    TIM_TimeBaseInitStrue.TIM_Period = arr;
    TIM_TimeBaseInitStrue.TIM_Prescaler = psc;
    TIM_TimeBaseInitStrue.TIM_CounterMode =TIM_CounterMode_Up;
    TIM_TimeBaseInitStrue.TIM_ClockDivision =0;
    TIM_TimeBaseInit(TIM4,&TIM_TimeBaseInitStrue);

    TIM_OCInitTypeStrue.TIM_OCMode =TIM_OCMode_PWM1;
    TIM_OCInitTypeStrue.TIM_OCNPolarity =TIM_OCPolarity_Low;
    TIM_OCInitTypeStrue.TIM_OutputState =TIM_OutputState_Enable;               
    TIM_OC3Init(TIM4, &TIM_OCInitTypeStrue);

    TIM_OC3PreloadConfig(TIM4,TIM_OCPreload_Enable);
    TIM_Cmd(TIM4,ENABLE);
}

#include "led.h"
#include "delay.h"
#include "pwm.h"
#include "sys.h"
#include "Stm32f10x.h"
#include "usart.h"

u16 led0pwmval;
int main(void)
{      

    u8 dir=1;
    delay_init();
   NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
    uart_init(115200);
    LED_Init();
    TIM4_PWM_Init(899,0);
    while(1)
    {
        delay_ms(10);
        if(dir == 1) led0pwmval++;
        else led0pwmval--;

        if(led0pwmval>300) dir = 0;
        if(led0pwmval==0) dir = 1;
        TIM_SetCompare3(TIM4,led0pwmval);
    }
}

x962239349

已经弄懂了，当前引脚没有与LED灯引脚对应，需要杜邦线连接