【蓝桥杯嵌入式】4_key：单击+长按+双击

1、电路图

将4个按键的引脚设置为input，并将初始状态设置为Pull-up（上拉输入）

为解决按键抖动的问题，我们使用定时器中断进行消抖

打开TIM3时钟并设置参数，中断间隔10ms，当计数达到10000时溢出。80M/80/10000=100，1/100=0.01s=10ms

1、Prescaler (PSC - 16 bits value): 预分频器，用于分频器计数器时钟。设置为 80-1 表示时钟频率将被分频 80。

2、Counter Mode: 计数器模式，这里设置为 "Up"，意味着计数器将从 0 开始向上计数，直到达到自动重装载寄存器的值。

3、Dithering: 抖动功能，用于减少电磁干扰（EMI）。这里设置为 "Disable"，表示禁用抖动。

4、Counter Period (AutoReload Register ...): 计数器周期，即自动重装载寄存器的值。设置为 10000-1 表示计数器将从 0 计数到 9999，然后重置为 0。

5、Internal Clock Division (CKD): 内部时钟分频，这里设置为 "No Division"，表示内部时钟没有被进一步分频。

6、auto-reload preload: 自动重装载预加载，这里设置为 "Disable"，表示在更新事件后立即加载新的周期值，而不是在下一个更新事件之前。

7、Master/Slave Mode (MSM bit): 主/从模式，这里设置为 "Disable"，表示定时器工作在独立模式，不作为从属定时器。

8、Trigger Event Selection TRGO: 触发事件选择，这里设置为 "Reset (UG bit from TIMx_EGR)"，意味着当更新事件（Update Event）发生时，TRGO（触发输出）将被重置。

打开定时器中断

2、代码

2.1 单击+长按

（1）internet.c

#include "interrupt.h"struct keys key[4]={0};void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{if(htim->Instance==TIM3){key[0].key_sta=HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_0);key[1].key_sta=HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_1);key[2].key_sta=HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_2);key[3].key_sta=HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_0);for(uchar i=0;i<4;i++)	   //遍历4个按键{//break跳出switch循环后再进行4次for循环，循环结束后在10ms后中断再进入循环。消抖用的一般都是延时，但该程序已将定时器配置为10mswitch(key[i].judge_sta){case 0:{if(key[i].key_sta==0) //如果key[i].key_sta==0，按键按下，但不能肯定，进入第二步{key[i].judge_sta=1;key[i].key_time=0;}break;				}case 1:{if(key[i].key_sta==0) 	 //如果10ms后判断还是0，则确认是按下{key[i].judge_sta=2;  //进入第三步判断松手}else{key[i].judge_sta=0;}break;					}case 2:{if(key[i].key_sta==1) 	 //如果是1，则说明按键被松开{key[i].judge_sta=0;  //回到初始状态if(key[i].key_time<=70){key[i].single_flag=1;//标志位置1}}else{key[i].key_time++;if(key[i].key_time>70) //按键按下超过700ms则判断为长按，因为10ms执行一次，所以设置为70{key[i].long_flag=1;}}					}break;}}}
}

（2）internet.h

#ifndef _INTERRUPT_H_
#define _INTERRUPT_H_#include "main.h"
#include "stdbool.h"struct keys
{uchar judge_sta;bool key_sta;bool single_flag;bool long_flag;uint key_time;
};void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim);
#endif

（3）main.c

/* USER CODE BEGIN Header */
/********************************************************************************* @file           : main.c* @brief          : Main program body******************************************************************************* @attention** Copyright (c) 2024 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "tim.h"
#include "gpio.h"/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "lcd.h"
#include "interrupt.h"
/* USER CODE END Includes *//* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
void key_pro(void);
extern struct keys key[4];/* USER CODE END PTD *//* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD *//* USER CODE END PD *//* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM *//* USER CODE END PM *//* Private variables ---------------------------------------------------------*//* USER CODE BEGIN PV *//* USER CODE END PV *//* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP *//* USER CODE END PFP *//* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 *//* USER CODE END 0 *//*** @brief  The application entry point.* @retval int*/
int main(void)
{/* USER CODE BEGIN 1 *//* USER CODE END 1 *//* MCU Configuration--------------------------------------------------------*//* Reset of all peripherals, Initializes the Flash interface and the Systick. */HAL_Init();/* USER CODE BEGIN Init *//* USER CODE END Init *//* Configure the system clock */SystemClock_Config();/* USER CODE BEGIN SysInit *//* USER CODE END SysInit *//* Initialize all configured peripherals */MX_GPIO_Init();MX_TIM3_Init();/* USER CODE BEGIN 2 */HAL_TIM_Base_Start_IT(&htim3);LCD_Init();//LCD ij ʼ    LCD_Clear(Black);LCD_SetBackColor(Black);LCD_SetTextColor(White);/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){key_pro();	  /* USER CODE END WHILE *//* USER CODE BEGIN 3 */}/* USER CODE END 3 */
}/*** @brief System Clock Configuration* @retval None*/
void SystemClock_Config(void)
{RCC_OscInitTypeDef RCC_OscInitStruct = {0};RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};/** Configure the main internal regulator output voltage*/HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);/** Initializes the RCC Oscillators according to the specified parameters* in the RCC_OscInitTypeDef structure.*/RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;RCC_OscInitStruct.HSEState = RCC_HSE_ON;RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV3;RCC_OscInitStruct.PLL.PLLN = 20;RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK){Error_Handler();}/** Initializes the CPU, AHB and APB buses clocks*/RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK){Error_Handler();}
}/* USER CODE BEGIN 4 */
void key_pro(void)
{if(key[0].single_flag==1){LCD_DisplayStringLine(Line0, (uchar *)"single_flag     ");key[0].single_flag=0;}if(key[0].long_flag==1){LCD_DisplayStringLine(Line0, (uchar *)"long_flag       ");key[0].long_flag=0;}if(key[0].double_flag==1){LCD_DisplayStringLine(Line0, (uchar *)"double_flag       ");key[0].double_flag=0;}
}
/* USER CODE END 4 *//*** @brief  This function is executed in case of error occurrence.* @retval None*/
void Error_Handler(void)
{/* USER CODE BEGIN Error_Handler_Debug *//* User can add his own implementation to report the HAL error return state */__disable_irq();while (1){}/* USER CODE END Error_Handler_Debug */
}#ifdef  USE_FULL_ASSERT
/*** @brief  Reports the name of the source file and the source line number*         where the assert_param error has occurred.* @param  file: pointer to the source file name* @param  line: assert_param error line source number* @retval None*/
void assert_failed(uint8_t *file, uint32_t line)
{/* USER CODE BEGIN 6 *//* User can add his own implementation to report the file name and line number,ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) *//* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

2.2 单击+长按+双击

（1）internet.c

#include "interrupt.h"struct keys key[4]={0};void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{if(htim->Instance==TIM3){key[0].key_sta=HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_0);key[1].key_sta=HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_1);key[2].key_sta=HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_2);key[3].key_sta=HAL_GPIO_ReadPin(GPIOA,GPIO_PIN_0);for(int i=0;i<4;i++)	   //遍历4个按键{switch(key[i].judge_sta){case 0:					//按下检测{if(key[i].key_sta==0) {key[i].judge_sta=1;key[i].key_time=0;}}break;case 1:					//消抖检测{if(key[i].key_sta==0) 	 //如果按键按下{key[i].judge_sta=2; 				}else{key[i].judge_sta=0;}}break;case 2:					//按键操作检测{if(key[i].key_sta==1 && key[i].key_time<70)  //如果按键松手，并且没有长按{if(key[i].double_click_en==0)				//按键第一次按下{key[i].double_click_en=1;				key[i].double_click_time=0;			//松手时间清零，准备计时}else									//click_en=1，按键第二次按下{key[i].double_flag=1;				key[i].double_click_en=0;				//click_en清零}key[i].judge_sta=0;}else if(key[i].key_sta==1 && key[i].key_time>=70)//如果按键松手，并且有长按，不执行操作{key[i].judge_sta=0;}else											//如果按键没有松手，判断是否为长按{if(key[i].key_time>=70)//按下700ms为长按{key[i].long_flag=1;}key[i].key_time++;	 			        }}break;}if(key[i].double_click_en==1)     //按键第一次按下后{key[i].double_click_time++;if(key[i].double_click_time>=30)//双击时间间隔为300ms{key[i].single_flag=1;key[i].double_click_en=0;}}}}
}

（2）internet.h

#ifndef _INTERRUPT_H_
#define _INTERRUPT_H_#include "main.h"
#include "stdbool.h"struct keys
{uchar judge_sta;bool key_sta;bool single_flag;bool double_flag;bool long_flag;uint key_time;
uint double_click_time;         
uint double_click_en;      	
};void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim);
#endif

（3）main.c

/* USER CODE BEGIN Header */
/********************************************************************************* @file           : main.c* @brief          : Main program body******************************************************************************* @attention** Copyright (c) 2024 STMicroelectronics.* All rights reserved.** This software is licensed under terms that can be found in the LICENSE file* in the root directory of this software component.* If no LICENSE file comes with this software, it is provided AS-IS.********************************************************************************/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "tim.h"
#include "gpio.h"/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "lcd.h"
#include "interrupt.h"
/* USER CODE END Includes *//* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
void key_pro(void);extern struct keys key[4];/* USER CODE END PTD *//* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD *//* USER CODE END PD *//* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM *//* USER CODE END PM *//* Private variables ---------------------------------------------------------*//* USER CODE BEGIN PV *//* USER CODE END PV *//* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
/* USER CODE BEGIN PFP *//* USER CODE END PFP *//* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 *//* USER CODE END 0 *//*** @brief  The application entry point.* @retval int*/
int main(void)
{/* USER CODE BEGIN 1 *//* USER CODE END 1 *//* MCU Configuration--------------------------------------------------------*//* Reset of all peripherals, Initializes the Flash interface and the Systick. */HAL_Init();/* USER CODE BEGIN Init *//* USER CODE END Init *//* Configure the system clock */SystemClock_Config();/* USER CODE BEGIN SysInit *//* USER CODE END SysInit *//* Initialize all configured peripherals */MX_GPIO_Init();MX_TIM3_Init();/* USER CODE BEGIN 2 */HAL_TIM_Base_Start_IT(&htim3);LCD_Init();//LCD ij ʼ    LCD_Clear(Black);LCD_SetBackColor(Black);LCD_SetTextColor(White);/* USER CODE END 2 *//* Infinite loop *//* USER CODE BEGIN WHILE */while (1){key_pro();	  /* USER CODE END WHILE *//* USER CODE BEGIN 3 */}/* USER CODE END 3 */
}/*** @brief System Clock Configuration* @retval None*/
void SystemClock_Config(void)
{RCC_OscInitTypeDef RCC_OscInitStruct = {0};RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};/** Configure the main internal regulator output voltage*/HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1);/** Initializes the RCC Oscillators according to the specified parameters* in the RCC_OscInitTypeDef structure.*/RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;RCC_OscInitStruct.HSEState = RCC_HSE_ON;RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV3;RCC_OscInitStruct.PLL.PLLN = 20;RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK){Error_Handler();}/** Initializes the CPU, AHB and APB buses clocks*/RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK){Error_Handler();}
}/* USER CODE BEGIN 4 */
void key_pro(void)
{if(key[0].single_flag==1){LCD_DisplayStringLine(Line0, (uchar *)"single_flag     ");key[0].single_flag=0;}if(key[0].long_flag==1){LCD_DisplayStringLine(Line0, (uchar *)"long_flag       ");key[0].long_flag=0;}if(key[0].double_flag==1){LCD_DisplayStringLine(Line0, (uchar *)"double_flag       ");key[0].double_flag=0;}
}
/* USER CODE END 4 *//*** @brief  This function is executed in case of error occurrence.* @retval None*/
void Error_Handler(void)
{/* USER CODE BEGIN Error_Handler_Debug *//* User can add his own implementation to report the HAL error return state */__disable_irq();while (1){}/* USER CODE END Error_Handler_Debug */
}#ifdef  USE_FULL_ASSERT
/*** @brief  Reports the name of the source file and the source line number*         where the assert_param error has occurred.* @param  file: pointer to the source file name* @param  line: assert_param error line source number* @retval None*/
void assert_failed(uint8_t *file, uint32_t line)
{/* USER CODE BEGIN 6 *//* User can add his own implementation to report the file name and line number,ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) *//* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */