外部中断
- 此方法需注意Timer base（也就是HAL_Delay）的优先级，要低于外部中断的优先级，否则会卡死，推荐下面状态机实现的方法。
- 上拉输入：
if (HAL_GPIO_ReadPin(KEY_GPIO_Port, KEY_Pin) == GPIO_PIN_SET) { // 按下OSTimeDly(20,OS_OPT_TIME_DLY,&err); // 去抖if (HAL_GPIO_ReadPin(KEY_GPIO_Port, KEY_Pin) == GPIO_PIN_SET) {/* 用户代码 */}}
- 长按短按：
if (HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_12) == GPIO_PIN_RESET) { // 按下HAL_Delay(20); // 去抖if (HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_12) == GPIO_PIN_RESET) { HAL_Delay(500); // 判断长按if (HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_12) == GPIO_PIN_RESET) { /* 长按 */ } else {/* 短按 */}}}
状态机实现多按键短按长按
key.c
#include "key.h"#define KEY_NUM 3
#define LONG_PRESS_TIME 1000
#define DEBOUNCE_TIME 20Key_t keys[KEY_NUM];/*** @brief 初始化按键接口参数*/
void Key_Init(void)
{keys[0].port = KEY_L_GPIO_Port;keys[0].pin = KEY_L_Pin;keys[0].active_level = 1;keys[0].state = KEY_IDLE;keys[0].last_level = 0;keys[1].port = KEY_M_GPIO_Port;keys[1].pin = KEY_M_Pin;keys[1].active_level = 0;keys[1].state = KEY_IDLE;keys[1].last_level = 1;keys[2].port = KEY_R_GPIO_Port;keys[2].pin = KEY_R_Pin;keys[2].active_level = 0;keys[2].state = KEY_IDLE;keys[2].last_level = 1;
}/*** @brief 按键扫描函数* @retval result.key_id 按键id* @retval result.event 事件类型*/
KeyEvent_t Key_Scan(void)
{KeyEvent_t result = {0, KEY_EVENT_NONE};for(uint8_t i = 0; i < KEY_NUM; i++){bool current_level;if (HAL_GPIO_ReadPin(keys[i].port, keys[i].pin) == keys[i].active_level){current_level = 1;}else current_level = 0;switch (keys[i].state){case KEY_IDLE:if (current_level && !keys[i].last_level){keys[i].state = KEY_PRESSED;keys[i].timer = HAL_GetTick();}break;case KEY_PRESSED:if (current_level){if (HAL_GetTick() - keys[i].timer >= DEBOUNCE_TIME){keys[i].state = KEY_HOLD;} }else keys[i].state = KEY_IDLE;break;case KEY_HOLD:if (current_level){if (HAL_GetTick() - keys[i].timer >= LONG_PRESS_TIME){result.key_id = i;result.event = KEY_EVENT_LONG;keys[i].state = KEY_RELEASED;keys[i].last_level = current_level;return result; // 长按事件}}else{if (HAL_GetTick() - keys[i].timer >= DEBOUNCE_TIME){result.key_id = i;result.event = KEY_EVENT_SHORT;keys[i].state = KEY_IDLE;keys[i].last_level = current_level;return result; // 短按事件}else keys[i].state = KEY_RELEASED;}break;case KEY_RELEASED:if (!current_level && (HAL_GetTick() - keys[i].timer >= DEBOUNCE_TIME)){keys[i].state = KEY_IDLE;}break;default:break;}keys[i].last_level = current_level;}return result;
}key.h
#ifndef __KEY_H
#define __KEY_H#include "main.h"#include <stdbool.h>// 按键状态枚举
typedef enum {KEY_IDLE, // 空闲KEY_PRESSED, // 按下（去抖中）KEY_HOLD, // 持续按下KEY_RELEASED // 释放（去抖中）
} KeyState;// 按键事件枚举
typedef enum {KEY_EVENT_NONE, // 无事件KEY_EVENT_SHORT, // 短按KEY_EVENT_LONG // 长按
} KeyEvent;// 按键事件返回结构体
typedef struct {uint8_t key_id; // 按键IDKeyEvent event; // 事件类型
} KeyEvent_t;// 按键结构体
typedef struct {GPIO_TypeDef* port; // GPIO端口uint16_t pin; // GPIO引脚bool active_level; // 按下时的有效电平（true: 高电平, false: 低电平）KeyState state; // 当前状态uint32_t timer; // 计时器bool last_level; // 上次电平
} Key_t;void Key_Init(void);
KeyEvent_t Key_Scan(void);#endif实现方法
在main.c文件中：
#include "key.h"KeyEvent_t key;void main(void)
{Key_Init();while (1){key = Key_Scan();if (key.event != KEY_EVENT_NONE){switch (key.event){case KEY_EVENT_SHORT:printf("key %d short press\n", key.key_id);break;case KEY_EVENT_LONG:printf("key %d long press\n", key.key_id);break;default:break;}}}
}