python - 在 Tkinter 文本框中显示时，发出处理从串行端口读取的数据

Question

所以我正在从串行连接读取(并用 tkinter 文本框显示)数据，但我无法按照我的意愿处理返回的数据，以便运行我的测试。更简单地说，即使 machine response = 0x1显示，我无法从全局读取 serBuffer .

在将其显示给 textbox 之前我会从测试内部读取 function然后检查响应是否在 string 中，但现在我将读取的数据(字符串)传递给全局变量，然后尝试读取它，它似乎不起作用，除非我删除 serBuffer = ""来自 readserial .但这会导致一个新问题。当我按下按钮发送命令时，它会发送它，但仅在我第二次按下它之后才会收到响应，之后每次都收到响应。所以结果我得到了 Fail如果我运行一次测试，但每次都通过。

图片与想要的回复 ( test function 不读取 0x1 并始终返回 FAIL)



图片与不想要的 响应(只有在第二次按下它之后才会收到响应，之后每次都收到响应。因此，如果我运行一次测试，我会得到一个失败，但我每次都通过)。

import tkinter as tk
import serial
from serial import *


serialPort = "COM3"
baudRate = 115200
ser = Serial(serialPort, baudRate, timeout=0, writeTimeout=0) #ensure non-blocking


#make a TkInter Window
mainWindow = tk.Tk()
mainWindow.wm_title("Reading Serial")
mainWindow.geometry('1650x1000+500+100')




scrollbar = tk.Scrollbar(mainWindow)
scrollbar.pack(side=tk.RIGHT, fill=tk.Y)

log = tk.Text ( mainWindow, width=60, height=60, takefocus=0)
log.pack()

log.config(yscrollcommand=scrollbar.set)
scrollbar.config(command=log.yview)

#make our own buffer
#useful for parsing commands
#Serial.readline seems unreliable at times too
serBuffer = ""
ser.write(b'\r\n')

def readSerial():
    while True:
        c = (ser.read().decode('utf-8', 'ignore'))  # attempt to read a character from Serial
        # was anything read?
        if len(c) == 0:
            break

        # get the buffer from outside of this function
        global serBuffer

        # check if character is a delimeter
        if c == '\r':
            serBuffer += "\n" # don't want returns. chuck it

        if c == '\n':
            serBuffer += "\n"  # add the newline to the buffer

            # add the line to the TOP of the log
            log.insert('1.1', serBuffer)
            serBuffer = ""  # empty the buffer
        else:
            serBuffer += c  # add to the buffer

    mainWindow.after(100, readSerial)  # check serial again soon

def test():
    command = b" test command \r\n"
    ser.write(command)
    global serBuffer
    time.sleep(0.5)
    if "0x1" in serBuffer:
        print('PASS')
        return 'PASS'
    else:
        print('FAIL')
        return 'FAIL'

button = tk.Button(mainWindow, text="Pone Test", font=40, bg='#b1c62d', command=test)
button.place(relx=0.8, rely=0, relwidth=0.1, relheight=0.05)


# after initializing serial, an arduino may need a bit of time to reset
mainWindow.after(100, readSerial)

mainWindow.mainloop()

Answer 1

Comment: but only receives the response after the second time a press it, and every time after. So as a result i get a Fail if i run the test once, but i get a pass everytime after

提高第一个，从 100 超时至 500矿石更多。

        # after initializing serial, an arduino may need a bit of time to reset
        mainWindow.after(100, self.readSerial)

欲知 延迟 对于第一个响应，请尝试以下操作:

Note: You have to do this without running def readSerial, to prevent concurent empty the in buffer"

    command = b" test command \r\n"
    self.ser.write(command)

    delay = 0.0

    # wait until you get `.in_waiting` data.
    while not self.ser.in_waiting:
        time.sleep(0.1)
        delay += 0.1
        print('.', end='')
        if delay >= 10:
            print('BREAK after {} no in_waiting'.format(int(delay * 10)))
            break

    print('Delay:{}, in_waiting:{}'.format(delay, self.ser.in_waiting))

以下对我有用。

Note: I use OOP syntax.

last_command

serBuffer = ""
last_command = None

复制准备好 read_buffer至 last_command , 仅空 read_buffer

def readSerial(self):
    while True:
        c = (self.ser.read().decode('utf-8', 'ignore'))  # attempt to read a character from Serial
        # was anything read?
        if len(c) == 0:
            break

        # get the buffer from outside of this function
        global serBuffer

        # check if character is a delimeter
        if c == '\r':
            serBuffer += "\n"  # don't want returns. chuck it

        if c == '\n':
            serBuffer += "\n"  # add the newline to the buffer

            global last_command
            last_command = serBuffer

            # add the line to the TOP of the log
            # log.insert('1.1', last_command)
            print('readSerial.last_command:"{}"'.format(bytes(last_command, 'utf-8')))

            serBuffer = ""  # empty the buffer

        else:
            serBuffer += c  # add to the buffer
            print('readSerial:"{}"'.format(bytes(serBuffer, 'utf-8')))

    self.after(100, self.readSerial)  # check serial again soon

做 test()

def test(self, write=True):
    print('test(write={})'.format(write))

    if write:
        command = b" test command \r\n"
        self.ser.write(command)
        self.after(500, self.test, False)

    elif last_command is not None:
        print('last_command:{}'.format(bytes(last_command, 'utf-8')))

        if "0x1" in last_command:
            print('PASS')
        else:
            print('FAIL')
    else:
        # ATTENTION: This could lead to a infinit loop
        # self.after(500, self.test, False)
        pass

Output:

test(write=True)
readSerial:"b' '"
readSerial:"b' t'"
readSerial:"b' te'"
readSerial:"b' tes'"
readSerial:"b' test'"
readSerial:"b' test '"
readSerial:"b' test c'"
readSerial:"b' test co'"
readSerial:"b' test com'"
readSerial:"b' test comm'"
readSerial:"b' test comma'"
readSerial:"b' test comman'"
readSerial:"b' test command'"
readSerial:"b' test command '"
readSerial:"b' test command \n\r'"
readSerial.last_command:"b' test command \n\r\n'"
test(write=False)
last_command:b' test command \n\r\n'
FAIL

Note: I get FAIL, because there is no 0x1 in last_command as i use PORT = 'loop://' which echo what is writen!