int button_state = GPIO_PIN_RESET; int button_prev_state = GPIO_PIN_RESET; int led_state = GPIO_PIN_RESET; while (1) { button_state = HAL_GPIO_ReadPin(GPIOC, GPIO_PIN_13); if (button_state != button_prev_state) { button_prev_state = button_state; if (button_state == GPIO_PIN_SET) { led_state = !led_state; if (led_state == GPIO_PIN_SET) { HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_SET); } else { HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_RESET); } } HAL_Delay(200); } }

这段代码是一个基础的嵌入式系统的循环程序，主要实现了一个按键控制LED灯的开关。代码中使用了 STM32 HAL 库，通过读取 GPIOC 的 13 号引脚的状态来检测按键是否被按下，当检测到按键状态发生变化时，根据当前 LED 灯的状态来切换灯的开关状态，并将开关状态写入 GPIOA 的 5 号引脚。这个循环程序会一直运行，每 200ms 检测一次按键状态。

相关问题

void button_handler(struct Button* handle) { uint8_t read_gpio_level = handle->hal_button_Level(handle->button_id); //ticks counter working.. if((handle->state) > 0) handle->ticks++; /*------------button debounce handle---------------*/ if(read_gpio_level != handle->button_level) { //not equal to prev one //continue read 3 times same new level change if(++(handle->debounce_cnt) >= DEBOUNCE_TICKS) { handle->button_level = read_gpio_level; handle->debounce_cnt = 0; } } else { //leved not change ,counter reset. handle->debounce_cnt = 0; } /*-----------------State machine-------------------*/ switch (handle->state) { case 0: if(handle->button_level == handle->active_level) { //start press down handle->event = (uint8_t)PRESS_DOWN; EVENT_CB(PRESS_DOWN); handle->ticks = 0; handle->repeat = 1; handle->state = 1; } else { handle->event = (uint8_t)NONE_PRESS; } break; case 1: if(handle->button_level != handle->active_level) { //released press up handle->event = (uint8_t)PRESS_UP; EVENT_CB(PRESS_UP); handle->ticks = 0; handle->state = 2; } else if(handle->ticks > LONG_TICKS) { handle->event = (uint8_t)LONG_PRESS_START; EVENT_CB(LONG_PRESS_START); handle->state = 5; } break; case 2: if(handle->button_level == handle->active_level) { //press down again handle->event = (uint8_t)PRESS_DOWN; EVENT_CB(PRESS_DOWN); handle->repeat++; EVENT_CB(PRESS_REPEAT); // repeat hit handle->ticks = 0; handle->state = 3; } else if(handle->ticks > SHORT_TICKS) { //released timeout if(handle->repeat == 1) { handle->event = (uint8_t)SINGLE_CLICK; EVENT_CB(SINGLE_CLICK); } else if(handle->repeat == 2) { handle->event = (uint8_t)DOUBLe_CLICK; EVENT_CB(DOUBLe_CLICK); // repeat hit } handle->state = 0; } break; case 3: if(handle->button_level != handle->active_level) { //released press up handle->event = (uint8_t)PRESS_UP; EVENT_CB(PRESS_UP); if(handle->ticks < SHORT_TICKS) { handle->ticks = 0; handle->state = 2; //repeat press } else { handle->state = 0; } }else if(handle->ticks > SHORT_TICKS){ // long press up handle->state = 0; } break; case 5: if(handle->button_level == handle->active_level) { //continue hold trigger handle->event = (uint8_t)LONG_PRESS_HOLD; EVENT_CB(LONG_PRESS_HOLD); } else { //releasd handle->event = (uint8_t)PRESS_UP; EVENT_CB(PRESS_UP); handle->state = 0; //reset } break; default: handle->state = 0; //reset break; } }帮我详细注释这段代码

这段代码是一个按键处理函数，主要用于处理按键的状态和事件。下面是对代码的详细注释：

void button_handler(struct Button* handle) { 
    // 读取按键GPIO端口的电平值
    uint8_t read_gpio_level = handle->hal_button_Level(handle->button_id);   
    // 计数器开始工作
    if((handle->state) > 0) handle->ticks++; 

    /*------------按键消抖处理---------------*/
    if(read_gpio_level != handle->button_level) { //如果读到的电平值不同于之前的
        //连续读取3次相同的电平值
        if(++(handle->debounce_cnt) >= DEBOUNCE_TICKS) {
            handle->button_level = read_gpio_level; //更新电平值
            handle->debounce_cnt = 0; //重置消抖计数器
        }
    } else { //如果电平值没有变化，重置消抖计数器
        handle->debounce_cnt = 0;
    }

    /*-----------------状态机处理-------------------*/
    switch (handle->state) {
    case 0: //初始状态
        if(handle->button_level == handle->active_level) { //按键按下
            handle->event = (uint8_t)PRESS_DOWN; //设置按键事件
            EVENT_CB(PRESS_DOWN); //触发事件回调函数
            handle->ticks = 0; //重置计数器
            handle->repeat = 1; //重置按键重复次数
            handle->state = 1; //进入下一个状态
        } else {
            handle->event = (uint8_t)NONE_PRESS; //没有按键按下
        }
        break;

    case 1: //按键按下状态
        if(handle->button_level != handle->active_level) { //按键松开
            handle->event = (uint8_t)PRESS_UP; //设置按键事件
            EVENT_CB(PRESS_UP); //触发事件回调函数
            handle->ticks = 0; //重置计数器
            handle->state = 2; //进入下一个状态
        } else if(handle->ticks > LONG_TICKS) { //按键按下超过长按时间
            handle->event = (uint8_t)LONG_PRESS_START; //设置按键事件
            EVENT_CB(LONG_PRESS_START); //触发事件回调函数
            handle->state = 5; //进入下一个状态
        }
        break;

    case 2: //单次按键按下后的状态
        if(handle->button_level == handle->active_level) { //按键再次按下
            handle->event = (uint8_t)PRESS_DOWN; //设置按键事件
            EVENT_CB(PRESS_DOWN); //触发事件回调函数
            handle->repeat++; //增加按键重复次数
            EVENT_CB(PRESS_REPEAT); //触发按键重复事件回调函数
            handle->ticks = 0; //重置计数器
            handle->state = 3; //进入下一个状态
        } else if(handle->ticks > SHORT_TICKS) { //按键松开超过短按时间
            if(handle->repeat == 1) { //单击事件
                handle->event = (uint8_t)SINGLE_CLICK; //设置按键事件
                EVENT_CB(SINGLE_CLICK); //触发事件回调函数
            } else if(handle->repeat == 2) { //双击事件
                handle->event = (uint8_t)DOUBLE_CLICK; //设置按键事件
                EVENT_CB(DOUBLE_CLICK); //触发事件回调函数
            }
            handle->state = 0; //回到初始状态
        }
        break;

    case 3: //按键重复状态
        if(handle->button_level != handle->active_level) { //按键松开
            handle->event = (uint8_t)PRESS_UP; //设置按键事件
            EVENT_CB(PRESS_UP); //触发事件回调函数
            if(handle->ticks < SHORT_TICKS) { //按键松开时间小于短按时间
                handle->ticks = 0; //重置计数器
                handle->state = 2; //回到单次按键按下后的状态
            } else { //按键松开时间大于等于短按时间
                handle->state = 0; //回到初始状态
            }
        } else if(handle->ticks > SHORT_TICKS){ //按键按下时间大于短按时间
            handle->state = 0; //回到初始状态
        }
        break;

    case 5: //长按状态
        if(handle->button_level == handle->active_level) { //按键继续按下
            handle->event = (uint8_t)LONG_PRESS_HOLD; //设置按键事件
            EVENT_CB(LONG_PRESS_HOLD); //触发事件回调函数
        } else { //按键松开
            handle->event = (uint8_t)PRESS_UP; //设置按键事件
            EVENT_CB(PRESS_UP); //触发事件回调函数
            handle->state = 0; //回到初始状态
        }
        break;

    default: //其他状态，回到初始状态
        handle->state = 0;
        break;
    }
}

STM32每按下一次数字发生改LED灯闪烁一次，数字未改变则不发生改变变

化。以下是一个简单的示例代码，实现了按下数字按钮控制LED灯闪烁的功能。假设数字按钮输入为GPIO_Pin_0，LED输出为GPIO_Pin_1：

#include "stm32f10x.h"

int main(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    EXTI_InitTypeDef EXTI_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    // 初始化GPIO口
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; // 按钮使用上拉输入模式
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    // 初始化外部中断线
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource0);
    EXTI_InitStructure.EXTI_Line = EXTI_Line0;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling; // 下降沿触发
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_Init(&EXTI_InitStructure);

    // 初始化中断向量表
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
    NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    // 循环检测数字按钮状态
    int prev_button_state = 1; // 上一次按钮状态
    int led_state = 0; // LED当前状态
    while (1)
    {
        int button_state = GPIO_ReadInputDataBit(GPIOA, GPIO_Pin_0);
        if (button_state == 0 && prev_button_state == 1) // 按钮从未按到按下
        {
            led_state = 1 - led_state; // 反转LED状态
            GPIO_WriteBit(GPIOA, GPIO_Pin_1, (led_state ? Bit_SET : Bit_RESET)); // 更新LED输出状态
        }
        prev_button_state = button_state;
    }
}

void EXTI0_IRQHandler(void)
{
    if (EXTI_GetITStatus(EXTI_Line0) != RESET)
    {
        EXTI_ClearITPendingBit(EXTI_Line0);
    }
}