目录

STM32移植嵌入式开源按键框架

MultiButton简介

multi_button.c文件

multi_button.h文件

按键事件

案例使用方法

学习剖析

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STM32移植嵌入式开源按键框架

今天移植了一款嵌入式按键框架工程MultiButton，MultiButton是一个小巧简单易用的事件驱动型按键驱动模块。

Github地址：GitHub - 0x1abin/MultiButton: Button driver for embedded system

现于2024.04.15进行移植，具体就两个文件：multi_button的c文件和h文件。

MultiButton简介

MultiButton 是一个小巧简单易用的事件驱动型按键驱动模块，可无限量扩展按键，按键事件的回调异步处理方式可以简化你的程序结构，去除冗余的按键处理硬编码，让你的按键业务逻辑更清晰。

multi_button.c文件

把license内容放到代码首段。

/** MIT License* Copyright (c) 2018 Zibin Zheng* * Permission is hereby granted, free of charge, to any person obtaining a copy* of this software and associated documentation files (the "Software"), to deal* in the Software without restriction, including without limitation the rights* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell* copies of the Software, and to permit persons to whom the Software is* furnished to do so, subject to the following conditions:* * The above copyright notice and this permission notice shall be included in all* copies or substantial portions of the Software.* * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE* SOFTWARE.*//* github:https://github.com/0x1abin/MultiButton */#include "driver_button.h"#define EVENT_CB(ev)   if(handle->cb[ev])handle->cb[ev]((void*)handle)
#define PRESS_REPEAT_MAX_NUM  15 /*!< The maximum value of the repeat counter *///button handle list head.
static struct Button* head_handle = NULL;static void button_handler(struct Button* handle);/*** @brief  Initializes the button struct handle.* @param  handle: the button handle struct.* @param  pin_level: read the HAL GPIO of the connected button level.* @param  active_level: pressed GPIO level.* @param  button_id: the button id.* @retval None*/
void button_init(struct Button* handle, uint8_t(*pin_level)(uint8_t), uint8_t active_level, uint8_t button_id)
{memset(handle, 0, sizeof(struct Button));handle->event = (uint8_t)NONE_PRESS;handle->hal_button_Level = pin_level;handle->button_level = handle->hal_button_Level(button_id);handle->active_level = active_level;handle->button_id = button_id;
}/*** @brief  Attach the button event callback function.* @param  handle: the button handle struct.* @param  event: trigger event type.* @param  cb: callback function.* @retval None*/
void button_attach(struct Button* handle, PressEvent event, BtnCallback cb)
{handle->cb[event] = cb;
}/*** @brief  Inquire the button event happen.* @param  handle: the button handle struct.* @retval button event.*/
PressEvent get_button_event(struct Button* handle)
{return (PressEvent)(handle->event);
}/*** @brief  Button driver core function, driver state machine.* @param  handle: the button handle struct.* @retval None*/
static 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 changeif(++(handle->debounce_cnt) >= DEBOUNCE_TICKS) {handle->button_level = read_gpio_level;handle->debounce_cnt = 0;}} else { //level not change ,counter reset.handle->debounce_cnt = 0;}/*-----------------State machine-------------------*/switch (handle->state) {case 0:if(handle->button_level == handle->active_level) {	//start press downhandle->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 uphandle->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 againhandle->event = (uint8_t)PRESS_DOWN;EVENT_CB(PRESS_DOWN);if(handle->repeat != PRESS_REPEAT_MAX_NUM) {handle->repeat++;}EVENT_CB(PRESS_REPEAT); // repeat hithandle->ticks = 0;handle->state = 3;} else if(handle->ticks > SHORT_TICKS) { //released timeoutif(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 uphandle->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) { // SHORT_TICKS < press down hold time < LONG_TICKShandle->state = 1;}break;case 5:if(handle->button_level == handle->active_level) {//continue hold triggerhandle->event = (uint8_t)LONG_PRESS_HOLD;EVENT_CB(LONG_PRESS_HOLD);} else { //releasedhandle->event = (uint8_t)PRESS_UP;EVENT_CB(PRESS_UP);handle->state = 0; //reset}break;default:handle->state = 0; //resetbreak;}
}/*** @brief  Start the button work, add the handle into work list.* @param  handle: target handle struct.* @retval 0: succeed. -1: already exist.*/
int button_start(struct Button* handle)
{struct Button* target = head_handle;while(target) {if(target == handle) return -1;	//already exist.target = target->next;}handle->next = head_handle;head_handle = handle;return 0;
}/*** @brief  Stop the button work, remove the handle off work list.* @param  handle: target handle struct.* @retval None*/
void button_stop(struct Button* handle)
{struct Button** curr;for(curr = &head_handle; *curr; ) {struct Button* entry = *curr;if(entry == handle) {*curr = entry->next;
//			free(entry);return;//glacier add 2021-8-18} else {curr = &entry->next;}}
}/*** @brief  background ticks, timer repeat invoking interval 5ms.* @param  None.* @retval None*/
void button_ticks(void)
{struct Button* target;for(target=head_handle; target; target=target->next) {button_handler(target);}
}

multi_button.h文件

extern使用函数，供外部文件使用。 

/** Copyright (c) 2016 Zibin Zheng <znbin@qq.com>* All rights reserved*/#ifndef _MULTI_BUTTON_H_
#define _MULTI_BUTTON_H_#include <stdint.h>
#include <string.h>//According to your need to modify the constants.
#define TICKS_INTERVAL    5	//ms
#define DEBOUNCE_TICKS    3	//MAX 7 (0 ~ 7)
#define SHORT_TICKS       (300 /TICKS_INTERVAL)		// ms
#define LONG_TICKS        (1000 /TICKS_INTERVAL)	// mstypedef void (*BtnCallback)(void*);typedef enum {PRESS_DOWN = 0,		/* 按键按下，每次按下都触发 */PRESS_UP,			/* 按键弹起，每次松开都触发 */PRESS_REPEAT,		/* 重复按下触发，变量repeat计数连击次数 */SINGLE_CLICK,		/* 单击按键事件 */DOUBLE_CLICK,		/* 双击按键事件 */LONG_PRESS_START,	/* 达到长按时间阈值时触发一次 */LONG_PRESS_HOLD,	/* 长按期间一直触发 */number_of_event,	/* 只为记录在此之前的事件次数 */NONE_PRESS			/* 默认状态，无按键按下 */
}PressEvent;typedef struct Button {uint16_t ticks;uint8_t  repeat : 4;								/* 重复按下次数，0~15 */uint8_t  event : 4;									/* 按键事件类型，默认NONE_PRESS，0~15 */uint8_t  state : 3;									/* 按键状态机状态：0~7 */uint8_t  debounce_cnt : 3;							/* 防抖次数，0~7 */uint8_t  active_level : 1;							/* 按键按下电平，0~1 */uint8_t  button_level : 1;							/* 按键电平，0~1 */uint8_t  button_id;									/* 按键id */uint8_t  (*hal_button_Level)(uint8_t button_id_);	/* 按键电平检测函数 */BtnCallback  cb[number_of_event];					/* 创建各事件处理函数数组 */struct Button* next;								/* 指向下一个按钮对象 */
}Button;#ifdef __cplusplus
extern "C" {
#endifextern void button_init(struct Button* handle, uint8_t(*pin_level)(uint8_t), uint8_t active_level, uint8_t button_id);	/* 初始化按键对象 */
extern void button_attach(struct Button* handle, PressEvent event, BtnCallback cb);	/* 注册按键事件 */
extern PressEvent get_button_event(struct Button* handle);
extern int  button_start(struct Button* handle);	/* 开始按键检测 */
extern void button_stop(struct Button* handle);		/* 停止按键检测 */
extern void button_ticks(void);#ifdef __cplusplus
}
#endif#endif

按键事件

事件	说明
PRESS_DOWN	按键按下，每次按下都触发
PRESS_UP	按键弹起，每次松开都触发
PRESS_REPEAT	重复按下触发，变量repeat计数连击次数
SINGLE_CLICK	单击按键事件
DOUBLE_CLICK	双击按键事件
LONG_PRESS_START	达到长按时间阈值时触发一次
LONG_PRESS_HOLD	长按期间一直触发

案例使用方法

结合自身项目需求实现。我使用到了FreeRTOS V2操作系统。

只需调用MultiButton_Init()函数初始化，调用xxx_Handler()函数处理。

#include "driver_button.h"enum Button_IDs 
{btn1_id,btn2_id,
};static osTimerId_t 	multiButtonTimer;
struct Button btn1;
struct Button btn2;static void MultiButtonTimerCallback (void *argument);
static uint8_t read_button_GPIO(uint8_t button_id);
static void BTN1_PRESS_CLICK_Handler(void* btn);
static void BTN2_PRESS_CLICK_Handler(void* btn);static uint8_t read_button_GPIO(uint8_t button_id)
{// you can share the GPIO read function with multiple Buttonsswitch(button_id){case btn1_id:return HAL_GPIO_ReadPin(OLED_KEY1_GPIO_Port, OLED_KEY1_Pin);case btn2_id:return !HAL_GPIO_ReadPin(USER_KEY_GPIO_Port, USER_KEY_Pin);default:return 0;}
}static void BTN1_PRESS_CLICK_Handler(void* btn)
{/* 事件处理时间不宜过长 *///do something...
}static void BTN2_PRESS_CLICK_Handler(void* btn)
{/* 事件处理时间不宜过长 *///do something...
}void MultiButton_Init(void)
{multiButtonTimer = osTimerNew(MultiButtonTimerCallback, osTimerPeriodic, NULL, NULL);/* 单按键初始化 */button_init(&btn1, read_button_GPIO, 0, btn1_id);	button_init(&btn2, read_button_GPIO, 0, btn2_id);/* 单按键注册，可单按键多事件注册 */button_attach(&btn1, SINGLE_CLICK,         BTN1_PRESS_CLICK_Handler);button_attach(&btn2, SINGLE_CLICK,         BTN2_PRESS_CLICK_Handler);/* 单按键检测 */button_start(&btn1);button_start(&btn2);osTimerStart(multiButtonTimer, 5); 		//启动定时器，5ms每轮
}/************************************************************************	5ms进一次定时器回调函数**********************************************************************/
static void MultiButtonTimerCallback (void *argument)
{button_ticks();
}

学习剖析

学习要点：

        按键各种类型事件。

        状态机思想。

        单向链表语法。

button_init()函数很简单，默认记录了单按键句柄的按键事件类型、按键此刻电平、按键按下电平、按键ID和按键电平检测函数。

使用方法：

button_init(&btn1, read_button_GPIO, 0, btn1_id);    // 低电平按下

button_attach()函数也很简单，注册按钮，即将按键处理函数放入单按键句柄的对应按键事件数组位置。

使用方法：

button_attach(&btn1, SINGLE_CLICK,         BTN1_PRESS_CLICK_Handler);

get_button_event()函数也很简单，获取当前单按键句柄的发生事件类型。

button_handler()函数采用了状态机的思想。大概思想如下：