中国建设银行属于什么类型网站,广告设计专业就业方向,中英文网站设计,网站建设属于无形资产点击蓝字关注我们因公众号更改推送规则#xff0c;请点“在看”并加“星标”第一时间获取精彩技术分享来源于网络#xff0c;侵删C 语言面向对象编程的最佳实践一、前言以STM32为例#xff0c;打开网络上下载的例程或者是购买开发板自带的例程#xff0c;都会发现应用层中会…点击蓝字关注我们因公众号更改推送规则请点“在看”并加“星标”第一时间获取精彩技术分享来源于网络侵删C 语言面向对象编程的最佳实践一、前言以STM32为例打开网络上下载的例程或者是购买开发板自带的例程都会发现应用层中会有stm32f10x.h或者stm32f10x_gpio.h这些文件严格来时属于硬件层的如果软件层出现这些文件会显得很乱。使用过Linux的童鞋们肯定知道linux系统无法直接操作硬件层打开linux或者rt_thread代码会发现代码中都会有device的源文件没错这就是驱动层。二、实现原理原理就是将硬件操作的接口全都放到驱动链表上在驱动层实现device的open、read、write等操作。当然这样做也有弊端就是驱动find的时候需要遍历一遍驱动链表这样会增加代码运行时间。三、代码实现国际惯例写代码先写头文件。rt_thread中使用的是双向链表为了简单在这我只用单向链表。有兴趣的可以自行研究rt_thread头文件接口:本次只实现如下接口device_open 和device_close等剩下的接口可以自行研究。这样就可以在应用层中只调用如下接口可实现/*
驱动注册
*/
int cola_device_register(cola_device_t *dev);/*
驱动查找
*/
cola_device_t *cola_device_find(const char *name);/*
驱动读
*/
int cola_device_read(cola_device_t *dev, int pos, void *buffer, int size);/*
驱动写
*/
int cola_device_write(cola_device_t *dev, int pos, const void *buffer, int size);/*
驱动控制
*/
int cola_device_ctrl(cola_device_t *dev, int cmd, void *arg);;头文件cola_device.h#ifndef _COLA_DEVICE_H_
#define _COLA_DEVICE_H_enum LED_state
{LED_OFF,LED_ON,LED_TOGGLE,
};typedef struct cola_device cola_device_t;
struct cola_device_ops
{
int (*init) (cola_device_t *dev);
int (*open) (cola_device_t *dev, int oflag);
int (*close) (cola_device_t *dev);
int (*read) (cola_device_t *dev, int pos, void *buffer, int size);
int (*write) (cola_device_t *dev, int pos, const void *buffer, int size);
int (*control)(cola_device_t *dev, int cmd, void *args);
};struct cola_device
{
const char * name;
struct cola_device_ops *dops;
struct cola_device *next;
};/*
驱动注册
*/
int cola_device_register(cola_device_t *dev);/*
驱动查找
*/
cola_device_t *cola_device_find(const char *name);/*
驱动读
*/
int cola_device_read(cola_device_t *dev, int pos, void *buffer, int size);/*
驱动写
*/
int cola_device_write(cola_device_t *dev, int pos, const void *buffer, int size);/*
驱动控制
*/
int cola_device_ctrl(cola_device_t *dev, int cmd, void *arg);#endif源文件cola_device.c#include cola_device.h
#include string.h
#include stdbool.hstruct cola_device *device_list NULL;/*
查找任务是否存在
*/
static bool cola_device_is_exists( cola_device_t *dev )
{
cola_device_t* cur device_list;
while( cur ! NULL ){
if( strcmp(cur-name,dev-name)0){ return true;} cur cur-next; } return false;
}static int device_list_inster(cola_device_t *dev)
{
cola_device_t *cur device_list;if(NULL device_list){device_list dev;dev-next NULL;}
else{
while(NULL ! cur-next){cur cur-next;}cur-next dev;dev-next NULL;}
return 1;
}/*
驱动注册
*/
int cola_device_register(cola_device_t *dev)
{
if((NULL dev) || (cola_device_is_exists(dev))){
return 0;}
if((NULL dev-name) || (NULL dev-dops)){
return 0;}
return device_list_inster(dev);
}/*
驱动查找
*/
cola_device_t *cola_device_find(const char *name)
{
cola_device_t* cur device_list;
while( cur ! NULL ){
if( strcmp(cur-name,name)0){
return cur;}cur cur-next;}
return NULL;
}/*
驱动读
*/
int cola_device_read(cola_device_t *dev, int pos, void *buffer, int size)
{
if(dev){
if(dev-dops-read){
return dev-dops-read(dev, pos, buffer, size);}}
return 0;
}/*
驱动写
*/
int cola_device_write(cola_device_t *dev, int pos, const void *buffer, int size)
{
if(dev){
if(dev-dops-write){
return dev-dops-write(dev, pos, buffer, size);}}
return 0;
}/*
驱动控制
*/
int cola_device_ctrl(cola_device_t *dev, int cmd, void *arg)
{
if(dev){
if(dev-dops-control){
return dev-dops-control(dev, cmd, arg);}}
return 0;
}硬件注册方式以LED为例初始化接口void led_register(void)需要在初始化中调用。#include stm32f0xx.h
#include led.h
#include cola_device.h
#define PORT_GREEN_LED GPIOC
#define PIN_GREENLED GPIO_Pin_13 /* LED亮、灭、变化 */
#define LED_GREEN_OFF (PORT_GREEN_LED-BSRR PIN_GREENLED)
#define LED_GREEN_ON (PORT_GREEN_LED-BRR PIN_GREENLED)
#define LED_GREEN_TOGGLE (PORT_GREEN_LED-ODR ^ PIN_GREENLED)static cola_device_t led_dev;static void led_gpio_init(void)
{GPIO_InitTypeDef GPIO_InitStructure;RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOC, ENABLE);GPIO_InitStructure.GPIO_Pin PIN_GREENLED; GPIO_InitStructure.GPIO_Mode GPIO_Mode_OUT; GPIO_InitStructure.GPIO_Speed GPIO_Speed_50MHz; GPIO_InitStructure.GPIO_OType GPIO_OType_PP; GPIO_InitStructure.GPIO_PuPd GPIO_PuPd_NOPULL; GPIO_Init(PORT_GREEN_LED, GPIO_InitStructure);LED_GREEN_OFF;
}static int led_ctrl(cola_device_t *dev, int cmd, void *args)
{
if(LED_TOGGLE cmd){LED_GREEN_TOGGLE;}
else {}
return 1;
}static struct cola_device_ops ops
{.control led_ctrl,
};void led_register(void)
{led_gpio_init();led_dev.dops ops;led_dev.name led;cola_device_register(led_dev);
}应用层app代码:#include string.h
#include app.h
#include config.h
#include cola_device.h
#include cola_os.hstatic task_t timer_500ms;
static cola_device_t *app_led_dev;//led每500ms状态改变一次
static void timer_500ms_cb(uint32_t event)
{cola_device_ctrl(app_led_dev,LED_TOGGLE,0);
}void app_init(void)
{app_led_dev cola_device_find(led);assert(app_led_dev);cola_timer_create(timer_500ms,timer_500ms_cb);cola_timer_start(timer_500ms,TIMER_ALWAYS,500);
}这样 app.c 文件中就不需要调用 led.h 头文件了rtt 就是这样实现的。四、总结这样就可以实现软硬件分层了是不是非常好用五、代码下载链接https://gitee.com/schuck/cola_os如果你年满18周岁以上又觉得学【C语言】太难想尝试其他编程语言那么我推荐你学Python现有价值499元Python零基础课程限时免费领取限10个名额▲扫描二维码-免费领取戳“阅读原文”我们一起进步
