重启后串口不能正常工作，除非我执行 minicom [英] Serial port doesn't work properly after reboot, unless I execute minicom

问题描述

我的程序是这样开始的:

My program begins like this:

#!/usr/bin/env python
import sys

from serial import Serial, EIGHTBITS, PARITY_NONE, STOPBITS_ONE

SERIAL_DEVICE = '/dev/ttyUSB0'

ser = Serial(SERIAL_DEVICE, timeout=2, baudrate=9600, bytesize=EIGHTBITS,
             parity=PARITY_NONE, stopbits=STOPBITS_ONE)

程序的下一部分向设备发送一些信息，然后等待响应.当我在重新启动后运行它时，它没有找到它期望的响应并以错误终止(这是正确的行为，除了它没有看到它期望的响应的事实).

The next part of the program sends something to the device and then expects a response. When I run it after reboot, it doesn't find the response it is expecting and terminates with an error (this is correct behavior apart from the fact that it doesn't see the response it expects).

但是，如果我运行 minicom 并通过 minicom 与设备通信，它工作正常.如果我关闭 minicom 并运行程序，它运行良好.minicom 配置有一个空的初始化字符串，我总是不重置就退出.

However, if I run minicom and talk to the device through minicom, it works fine. If then I close minicom and run the program, it runs fine. The minicom configuration has an empty initialization string and I always exit without reset.

不用说，minicom 具有相同的设置 AFAICS.它也有硬件控制，但我确实尝试将 rtscts=True 作为 Serial() 的参数并没有看到任何区别(即使我在参数中有错误，这并不能解释为什么在执行 minicom 后程序可以正常工作).

Needless to say, minicom has the same settings AFAICS. It also has hardware control on, but I did try rtscts=True as an argument to Serial() and saw no difference (and even if I had an error in the arguments, this doesn't explain why after executing minicom the program works properly).

推荐答案

您的症状表明您的程序没有将串行终端初始化为它所需的正确模式.

The symptom you have is an indication that your program is not initializing the serial terminal to the proper mode that it requires.

minicom 具有相同的设置 AFAICS

minicom has the same settings AFAICS

似乎您选择猜测而不是收集实际数据.
在使用 minicom 之前和之后使用 stty -a -F/dev/ttyUSB0.
主要区别在于 termios 模式可能默认为规范模式(重启后)，而 minicom 将其保留为非规范模式.

Seems like you choose to guess rather than gather actual data.
Use stty -a -F /dev/ttyUSB0 before and after using minicom.
The major difference is that the termios mode is probably canonical by default (after the reboot), and minicom leaves it in non-canonical mode.

在启动程序之前尝试使用 stty raw -F/dev/ttyUSB0.

Try using stty raw -F /dev/ttyUSB0 before starting your program.

这篇关于重启后串口不能正常工作，除非我执行 minicom的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！