Serial Monitor should handle disconnects more gracefully

Edit from maintainers - Temporary solution: https://docs.platformio.org/en/latest/faq/advanced-serial-monitor.html

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Serial Monitor should handle disconnects more gracefully

This is a bug report/feature request to improve the serial port functionality in Platform IO.

Configuration

Operating system: Windows 10 x64

PlatformIO Version (platformio --version): PlatformIO Core, version 5.1.1

Description of problem

Using serial monitor on a USB based serial port crashes with Exception

Steps to Reproduce

1. Start a serial monitor to a device with a USB based serial port: pio device monitor
2. Reset the device

Actual Results

Exception in thread rx:
Traceback (most recent call last):
  File "C:\Users\camer\.platformio\python3\lib\threading.py", line 926, in _bootstrap_inner
    self.run()
  File "C:\Users\camer\.platformio\python3\lib\threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
  File "c:\users\camer\.platformio\penv\lib\site-packages\serial\tools\miniterm.py", line 445, in reader
    data = self.serial.read(self.serial.in_waiting or 1)
  File "c:\users\camer\.platformio\penv\lib\site-packages\serial\serialwin32.py", line 257, in in_waiting
    raise SerialException("ClearCommError failed ({!r})".format(ctypes.WinError()))
serial.serialutil.SerialException: ClearCommError failed (PermissionError(13, 'The device does not recognize the command.', None, 22))

Expected Results

An error message designed for a novice user to understand.

Ideally also (optional) automatic reconnect when the device comes back.

[ivankravets]

Hi All!

Great news! Huge refactoring to the device monitor logic and it seems this issue has been solved. Also, automatic reconnection has been implemented.

Please re-test with pio upgrade --dev.

Does it work as expected now?

[m1cr0lab]

@ivankravets Thank you very much for this correction!