Device reports readiness to read but returned no data

Raspberry Pi Network HATs
1

Hi everyone,

I randomly get a weird error by running the gps python script while backing up some files to an external usb drive. I need some help to understand where does it come from.

I use a 3G/4G & LTE Base HAT (with the Quectel EC25 Mini PCle 4G/LTE Module). It is connected to a RaspberryPi 4 only through the usb cable.

Everything worked fine, my python script acquired accurate gps coordinates. But when I try to backup some files to an external usb drive at the same time (in another process), I get this error which crashes the 2 python processes (the one to acquire gps coordinates and the one to backup files). Is there a problem about serial (usb) ports ? May the RaspberryPi deliver enough energy to the 2 external devices (the hat and the external flash drive) ? Do you have ideas how I could perform further tests ? Here is the error I get: “serial.serialutil.SerialException: device”

Traceback (most recent call last):
  File "/home/pi/virtualenvs/Rasp2Web/lib/python3.7/site-packages/serial/serialposix.py", line 501, in read
    'device reports readiness to read but returned no data '
serial.serialutil.SerialException: device reports readiness to read but returned no data (device disconnected or multiple access on port?)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3.7/multiprocessing/process.py", line 297, in _bootstrap
    self.run()
  File "/usr/lib/python3.7/multiprocessing/process.py", line 99, in run
    self._target(*self._args, **self._kwargs)
  File "/home/pi/Dev/Rasp2Web/src/gps.py", line 37, in __init__
    self.receiving_gps()
  File "/home/pi/Dev/Rasp2Web/src/gps.py", line 51, in receiving_gps
    data = ser.readline()
  File "/home/pi/virtualenvs/Rasp2Web/lib/python3.7/site-packages/serial/serialposix.py", line 509, in read
    raise SerialException('read failed: {}'.format(e))
serial.serialutil.SerialException: read failed: device reports readiness to read but returned no data (device disconnected or multiple access on port?)

Thank you !