void Encoder_Init(void)
{

        RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);

        GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE);

        RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
        RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);

        GPIO_InitTypeDef GPIO_InitStructure;

        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_15;
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_Init(GPIOA, &GPIO_InitStructure);

        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
        GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_Init(GPIOB, &GPIO_InitStructure);




        EXTI_InitTypeDef EXTI_InitStructure;
        NVIC_InitTypeDef NVIC_InitStructure;

        GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource15);
        GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource3);

        EXTI_InitStructure.EXTI_Line =EXTI_Line4 | EXTI_Line15;
        EXTI_InitStructure.EXTI_LineCmd = ENABLE;
        EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
        EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
        EXTI_Init(&EXTI_InitStructure);

        NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);

        NVIC_InitStructure.NVIC_IRQChannel = EXTI15_10_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
        NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
        NVIC_Init(&NVIC_InitStructure);




        NVIC_InitStructure.NVIC_IRQChannel = EXTI4_IRQn;
        NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
        NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
        NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
        NVIC_Init(&NVIC_InitStructure);

}

void EXTI15_10_IRQHandler(void)
{
        if (EXTI_GetITStatus(EXTI_Line15) == SET)
        {
                /*如果出现数据乱跳的现象，可再次判断引脚电平，以避免抖动*/
                if (GPIO_ReadInputDataBit(GPIOA, GPIO_Pin_15) == 0)
                {
                        if (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_3) == 0)
                        {
                                Encoder_Count --;
                        }
                }
                EXTI_ClearITPendingBit(EXTI_Line15);
        }
}

void EXTI3_IRQHandler(void)
{
        if (EXTI_GetITStatus(EXTI_Line3) == SET)
        {
                /*如果出现数据乱跳的现象，可再次判断引脚电平，以避免抖动*/
                if (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_3) == 0)
                {
                        if (GPIO_ReadInputDataBit(GPIOB, GPIO_Pin_15) == 0)
                        {
                                Encoder_Count ++;
                        }
                }
                EXTI_ClearITPendingBit(EXTI_Line3);
        }
}

PB4是可以设置成外部中断的，PB3设置不了中断，也没有办法作为一般io使用

初步看了一下，楼主的代码中似乎连接了PB3的中断，但是却初始化了外部中断线4.

看看是不是这个原因导致外部中断3没有响应。

配置问题

楼主，您好。您这个配置中没有3的中断，是4的中断。

cy1370 发表于 2023-12-3 19:55
PB4是可以设置成外部中断的，PB3设置不了中断，也没有办法作为一般io使用
...

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE); GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE);

开始需要按照这样开启时钟顺序，必须先启用引脚重定义afio，再关闭SWD调试，就不会出现类似问题