由于串行端口打开情况，无法从 arduino 和无线调制解调器读取串行数据

Question

我之前发布过一些与此类似但更简单的复杂问题。主要问题是每当我从下拉菜单中选择端口并尝试打开它以从 Arduino 或无线调制解调器读取数据时。

每次都要面对串口打不开的错误。

我修复 COM 端口的硬代码工作得很好

下面提到的是我已简化并尝试使用的代码

import serial
import serial.tools.list_ports
from tkinter import *

ard = serial.Serial();
ard.baudrate = 9600

master = Tk()

variable = StringVar(master)

a=serial.tools.list_ports.comports()
for w in a: 
    print(w.device)
dev = [w.device]
print(dev)
variable.set(dev[0]) # default value
w = OptionMenu(master, variable, *dev)
w.pack()
ard.port = str(w)
ard.open
ard.is_open
#print(k)

def ok():
    print (variable.get())
    k = ard.readline()

button = Button(master, text="OK", command=ok)
button.pack()

mainloop()

但是每次我都遇到错误

COM4
['COM4']
COM4
Exception in Tkinter callback
Traceback (most recent call last):
  File "C:\Users\Misha\AppData\Local\Programs\Python\Python36\lib\tkinter\__init__.py", line 1702, in __call__
    return self.func(*args)
  File "C:\Users\Misha\Desktop\test\autoserial.py", line 27, in ok
    k = ard.readline()
  File "C:\Users\Misha\AppData\Local\Programs\Python\Python36\lib\site-packages\serial\serialwin32.py", line 267, in read
    raise portNotOpenError
serial.serialutil.SerialException: Attempting to use a port that is not open

请提供帮助我完成这项工作的建议，您的线索将对我有很大帮助。

Answer 1

您的代码中有 ard.open，但您实际上并没有调用该方法来打开串行连接。这就是为什么您会收到一条错误消息 Attempting to use a port that is not open。尝试 ard.open() 看看是否可行。这应该会打开您的端口并使其可用。

但是，根据您的设置，您可能希望将其包装在一个可以绑定到另一个按钮或 OptionMenu 的回调中。看来你会希望灵活选择端口，选择一个端口后才打开。

这是一个可能看起来像的小例子：

import tkinter as tk
import serial
import serial.tools.list_ports

ard = serial.Serial();
ard.baudrate = 9600

a = serial.tools.list_ports.comports()
ports = [port.device for port in a]

def open_serial():
    ard.port = variable.get()
    ard.open()
    print(f'Port {variable.get()} opened')

def close_serial():
    p = ard.port
    ard.close()
    print(f'Port {p} closed')

master = tk.Tk()
variable = tk.StringVar()
variable.set(ports[0])
options = tk.OptionMenu(master, variable, *ports)
options.pack()
button_open = tk.Button(master, text='Open', command=open_serial)
button_open.pack()
button_close = tk.Button(master, text='Close', command=close_serial)
button_close.pack()

tk.mainloop()

由于串行端口打开情况，无法从 arduino 和无线调制解调器读取串行数据

Not able to Read serial data from arduino and wireless modem due serial port opening case

python

serial-port

pyserial

python-3.x