【实例记录】在ubuntu上运行python实现与单片机多线程串口通信

怼烎@ 2022-10-07 10:52 8阅读 0赞

### 文章目录 ###

*  工具
 *   *  步骤

# 工具 #

工具：自己电脑双系统的ubuntu18.04,单片机esp8266,一个usb转ttl模块，ubuntu上已经下载了python的3.6和pip，还需要pip install serial  
首先在windows下测试板子是否能顺利收发数据：  
打开串口调试助手  
这里不需要用usb转ttl插windows的usb口，直接把esp8266连安卓线插上就好  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzU4NTc0_size_16_color_FFFFFF_t_70]  
板子里的程序是发1亮灯，发0关灯，发其他的则原样返回，可见结果是对的，亮灯也如预期。  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzU4NTc0_size_16_color_FFFFFF_t_70 1]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzU4NTc0_size_16_color_FFFFFF_t_70 2]

## 步骤 ##

模块和单片机连接：  
G-GND  
5V-VIN  
TXD-RX  
RXD-TX  
需要知识：串口通信 多线程 线程锁  
打开串口权限  
sudo chmod 777 /dev/ttyUSB0

注意杜邦线一定要接对，不然可能单片机没有上电都不知道  
写代码：

import threading
    import serial
    import time
    from time import sleep
    from threading import Lock
    from datetime import datetime
    loops=[2, 4]
    lock=Lock()
    date_time_format='%y-%M-%d %H:%M:%S'
    serial = serial.Serial('/dev/ttyUSB0', 115200, timeout=0.5)
    def date_time_str(date_time):
        return datetime.strftime(date_time, date_time_format)
    
    
    def loop(n_loop, n_sec):
        lock.acquire(blocking=True,timeout=2)
         
        serial.write("1".encode())
        sleep(n_sec)
        print(f'线程（{n_loop}）开始执行:{date_time_str(datetime.now())}，先休眠（{n_sec}）秒')
        
        serial.write("0".encode())
        sleep(n_sec)
        lock.release()
        print(f'线程（{n_loop}）休眠结束，结束于:{date_time_str(datetime.now())}')
    
    def begin(n_loop,sec):
        sleep(sec)
        serial.write("yes".encode())
        data = serial.read(20)
        print(data.decode())
    
    
    # 为线程定义一个函数
    
    def print_time(threadName, delay):
        serial.write("1".encode())
        sleep(delay)
     
        serial.write("0".encode())
        sleep(delay)
    
    
    def receive(threadName,delay):
        
        serial.write("999".encode())
        data = serial.read(20)
        print('this is'+str(data))
        sleep(delay)
    
    
    # 创建两个线程
    
    def main():
        print(f'---所有线程开始执行:{date_time_str(datetime.now())}')
        threads=[]
        n_loops=range(len(loops))
    
    
        t=threading.Thread(target=loop, args=(1, loops[0]))
        threads.append(t)
        m=threading.Thread(target=begin,args=(2,loops[1]))
        threads.append(m)
    
        for i in n_loops:      # start threads
            threads[i].start()
        for i in n_loops:  # wait for all
                threads[i].join()  # threads to finish
    
        print(f'---所有线程执行结束于:{date_time_str(datetime.now())}')
    
    
    if __name__ == '__main__':
        main()

结果：

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzU4NTc0_size_16_color_FFFFFF_t_70 3]

亮灯也成功了。

然后记录一下关于python的将字典转化为json:

import json
    
    print(json.dumps(list('abcde')))
    dict = { "time":1,"localtion":9.8}
    ni = json.dumps(dict)
    print(dict)
    print(ni)

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzU4NTc0_size_16_color_FFFFFF_t_70]: /images/20221005/f0785497e5f3425a9a98137d66e2b643.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzU4NTc0_size_16_color_FFFFFF_t_70 1]: /images/20221005/b6a0cb561c144bf996f56b67d4faaa73.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzU4NTc0_size_16_color_FFFFFF_t_70 2]: /images/20221005/53e5adfbc15c41bbb226525591795d6d.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxMzU4NTc0_size_16_color_FFFFFF_t_70 3]: /images/20221005/dd4314456c4e4faf83276672aafb9afb.png