RT-Thread-【2024-RSOC】多线程的学习分享笔记RT-Thread问答社区

【2024-RSOC】多线程的学习分享笔记

发布于 2024-07-23 20:53:58 浏览：263 订阅该版

[tocm]

##  DAY02 多线程学习
###一、线程属性
####1.1线程栈
RT-Thread线程具有独立的栈，线程切换时，会将当前线程的上下文存在栈中，要恢复时，在从中读取上下文，进行恢复
####1.2线程状态

![2e01029e6b96fb665d877523b83bc60.jpg](https://oss-club.rt-thread.org/uploads/20240723/7cdf3ceb9b50d52d55bedb6710ca171c.jpg.webp)
初始状态、就绪状态、运行状态、挂起状态、关闭状态
####1.3线程优先级
数值越小优先级越高，Cortex-M系列普遍采用32个优先级
####1.4时间片
时间片：时间片仅对优先级相同的就绪态线程有效
###二、线程调度

![微信图片_20240723202737.png](https://oss-club.rt-thread.org/uploads/20240723/a0183c74dcba1a61ebcae3777f464e49.png.webp)
###三、线程调度
####3.1线程创建与初始化
线程通过rt_thread_create或者rt_thread_init命令进入初始状态，即成功创建线程
####3.2线程启动
调用rt_thread_startup()进入就绪状态
####3.3线程运行
就绪状态的线程被调度器调度后进入运行状态
####3.4线程挂起
通过rt-thread_delay(),rt_sam_take()等函数或者获取不到资源时
####3.5线程关闭
调用rt_thread_delete()或者rt_thread_detach()将进入关闭状态
###四、代码实例
目标，采用两个不同优先级的线程。按键负责处理线程key，识别到按键按下输出“KEYDOWN”，按键未按下输出“KEYUP”。当按键KEY按下的时候，左侧led线程控制的红灯熄灭，未按下红灯亮起。key线程的优先级高于led线程
```c
/*
 * Copyright (c) 2023, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2023-07-06     Supperthomas first version
 * 2023-12-03     Meco Man     support nano version
 */

#include <board.h>
#include <rtthread.h>
#include <drv_gpio.h>
#ifndef RT_USING_NANO
#include <rtdevice.h>
#endif /* RT_USING_NANO */
#include <rtdbg.h>

rt_thread_t key,led;

#define GPIO_LED_B    GET_PIN(F, 11)
#define GPIO_LED_R    GET_PIN(F, 12)
// #define GPIO_BIN_RIGHT    GET_PIN(C, 4)
#define GPIO_BIN_LEFT   GET_PIN(C, 0)
unsigned char key_up_down;
void key_entry(void *p){
    unsigned char key_num;
    while (1){
        if(rt_pin_read(GPIO_BIN_LEFT)==0)
        {
            key_num = 1; //按键按下
            rt_kprintf("KEYDOWN\n");            
        }
        else if(rt_pin_read(GPIO_BIN_LEFT)==1)
        {
            key_num = 2; //按键没按下
            rt_kprintf("KEYUP\n");   
        }
        else key_num = 0;
        key_up_down = key_num;
        rt_thread_mdelay(15);
    }  
}
void led_entry(void *p){
    while (1){
        if (key_up_down == 1)
        {
        rt_pin_write(GPIO_LED_R, PIN_HIGH);            
        }
        else rt_pin_write(GPIO_LED_R, PIN_LOW);
        rt_kprintf("LEDrunning\n");        
        rt_thread_mdelay(50);
    }  
}
5
int main(void)
{
    // rt_pin_mode(GPIO_BIN_RIGHT,PIN_MODE_INPUT_PULLUP);//上拉输入
    rt_pin_mode(GPIO_BIN_LEFT,PIN_MODE_INPUT_PULLUP);//上拉输入
    
    rt_pin_mode(GPIO_LED_B,PIN_MODE_OUTPUT);
    rt_pin_mode(GPIO_LED_R,PIN_MODE_OUTPUT);

key = rt_thread_create("key",key_entry,RT_NULL,512,15,5);
    led = rt_thread_create("led",led_entry,RT_NULL,512,16,5);

if (key != RT_NULL)
    {
        rt_thread_startup(key);
    }
    else rt_kprintf("failed\n");
    if (led != RT_NULL)
    {
        rt_thread_startup(led);
    }
    else rt_kprintf("failed\n");       
    return RT_EOK;
}

```
###五、运行实录

![6a8615ad027182e4e158f4485821576.png](https://oss-club.rt-thread.org/uploads/20240723/db3b3411bd495567c97824674ab83d9f.png.webp)