长短按键的检测是国赛题里面遇到的，省赛没出过有两种实方法

定时器配置：

定时器的话要比delay准确，其中tim7定时器的准度最高

定时器预分配配置32 - 1，计数周期是10000 - 1这样做那么32MHZ/32也就是一秒钟记录10^6的数，计数周期配置10 ^ 4也就是说一个周期花费10 ^ 4/10 ^6秒也就是10ms

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim){  // 10ms// OLED_ShowString(0, "KEY)");COUNTNUMBER ++;
}

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1、普通按键实现：

普通按键我用的是矩阵按键模块的B1按键测试的

ROW1与ROW2配置为输入模式上拉，COLUMN1配置输出模式

void Function_KeyCheck(){HAL_GPIO_WritePin(COLUMN1_GPIO_Port, COLUMN1_Pin, GPIO_PIN_RESET);if(HAL_GPIO_ReadPin(ROW1_GPIO_Port, ROW1_Pin) == 0){  // 按键按下HAL_TIM_Base_Start_IT(&htim7);while(HAL_GPIO_ReadPin(ROW1_GPIO_Port, ROW1_Pin) == 0);  // 等待定时器关闭HAL_TIM_Base_Stop_IT(&htim7);if(COUNTNUMBER <= 100) KEYTIMEFLAG = 0;else KEYTIMEFLAG = 1;PRESSTIME = (float) COUNTNUMBER * 1.0 / 100;COUNTNUMBER = 0;}HAL_GPIO_WritePin(COLUMN1_GPIO_Port, COLUMN1_Pin, GPIO_PIN_SET);}

2、中断按键实现：

中断按键设置成上升沿和下降沿都会触发的模式，这样人按下按键就是下降沿这时候开定时器，松开就是上升沿，关定时器

void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin){  // 中断按键if(!HAL_GPIO_ReadPin(USER_Key_GPIO_Port, USER_Key_Pin)){  // 下降电平开启定时器HAL_TIM_Base_Start_IT(&htim7);}else{  // 上升电平关闭定时器并检测时间if(COUNTNUMBER <= 100) KEYTIMEFLAG = 0;else KEYTIMEFLAG = 1;PRESSTIME = (float) COUNTNUMBER * 1.0 / 100;COUNTNUMBER = 0;HAL_TIM_Base_Stop_IT(&htim7);}
}

完整代码：

Function.c

#include "Function.h"
#include "main.h"
#include "oled.h"
#include "i2c.h"
#include <stdio.h>
#include "tim.h"unsigned char KEYFLAG = 0;
unsigned char ARRAY[20];
char* LONGKEY = "long key press";
char* SHORTKEY = "short key press";
unsigned char KEYTIMEFLAG = 2;
float PRESSTIME = 0;uint32_t COUNTNUMBER = 0;  // 记录时间,这个区间必须要足够大void OLED_Write(unsigned char type, unsigned char data){unsigned char WriteData[2];WriteData[0] = type;WriteData[1] = data;HAL_I2C_Master_Transmit(&hi2c3, 0x78, WriteData, 2, 0xff);
}
void Function_OledInit(unsigned char ms){HAL_GPIO_WritePin(OLED_Power_GPIO_Port, OLED_Power_Pin, GPIO_PIN_RESET);HAL_Delay(ms);OLED_Init();
}void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim){  // 10ms// OLED_ShowString(0, "KEY)");COUNTNUMBER ++;
}void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin){  // 中断按键if(!HAL_GPIO_ReadPin(USER_Key_GPIO_Port, USER_Key_Pin)){  // 下降电平开启定时器HAL_TIM_Base_Start_IT(&htim7);}else{  // 上升电平关闭定时器并检测时间if(COUNTNUMBER <= 100) KEYTIMEFLAG = 0;else KEYTIMEFLAG = 1;PRESSTIME = (float) COUNTNUMBER * 1.0 / 100;COUNTNUMBER = 0;HAL_TIM_Base_Stop_IT(&htim7);}}void Function_KeyCheck(){HAL_GPIO_WritePin(COLUMN1_GPIO_Port, COLUMN1_Pin, GPIO_PIN_RESET);if(HAL_GPIO_ReadPin(ROW1_GPIO_Port, ROW1_Pin) == 0){  // 按键按下HAL_TIM_Base_Start_IT(&htim7);while(HAL_GPIO_ReadPin(ROW1_GPIO_Port, ROW1_Pin) == 0);  // 等待定时器关闭HAL_TIM_Base_Stop_IT(&htim7);if(COUNTNUMBER <= 100) KEYTIMEFLAG = 0;else KEYTIMEFLAG = 1;PRESSTIME = (float) COUNTNUMBER * 1.0 / 100;COUNTNUMBER = 0;}HAL_GPIO_WritePin(COLUMN1_GPIO_Port, COLUMN1_Pin, GPIO_PIN_SET);}void Function_MyMain(){Function_KeyCheck();if(KEYTIMEFLAG != 2){sprintf((char* )ARRAY, "%.2f s", PRESSTIME);if(KEYTIMEFLAG == 0){OLED_ShowString(0, (unsigned char* )SHORTKEY);}else if(KEYTIMEFLAG == 1){OLED_ShowString(0, (unsigned char* )LONGKEY);}OLED_ShowString(2, ARRAY);KEYTIMEFLAG = 2;}
}

Function.h

#ifndef __FUNCTION_H__
#define __FUNCTION_H__
#include "main.h"void OLED_Write(unsigned char type, unsigned char data);
void Function_OledInit(unsigned char ms);
void Function_MyMain();
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim);
void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin);#endif

效果：