Unexpected error while reading serial port

[djsixto]

What is the problem?

Unexpected error while reading serial port, please consult octoprint.log for details: SerialException: 'device reports readiness to read but returned no data (device disconnected or multiple access on port?)' @ comm.py:_readline:2916
Please see https://faq.octoprint.org/serialerror for possible reasons of this.
Changing monitoring state from "Printing" to "Offline (Error: SerialException: 'device reports readiness to read but returned no data (device disconnected or multiple access on port?)' @ comm.py:_readline:2916)"

What did you already try to solve it?

I have checked that the printer without octoprint works correctly, I have uploaded the error times offline

Complete Logs

2020-09-08 13:14:29,366 - octoprint.util.comm - ERROR - Unexpected error while reading from serial port
Traceback (most recent call last):
File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/util/comm.py", line 2916, in _readline
ret = self._serial.readline()
File "/home/pi/oprint/local/lib/python2.7/site-packages/octoprint/util/comm.py", line 5069, in readline
c = self.read(1)
File "/home/pi/oprint/local/lib/python2.7/site-packages/serial/serialposix.py", line 501, in read
'device reports readiness to read but returned no data '
SerialException: device reports readiness to read but returned no data (device disconnected or multiple access on port?)
2020-09-08 13:14:29,368 - octoprint.util.comm - ERROR - Please see https://faq.octoprint.org/serialerror for possible reasons of this.
2020-09-08 13:14:29,385 - octoprint.util.comm - INFO - Changing monitoring state from "Printing" to "Offline (Error: SerialException: 'device reports readiness to read but returned no data (device disconnected or multiple access on port?)' @ comm.py:_readline:2916)"
2020-09-08 13:14:29,400 - octoprint.plugins.action_command_notification - INFO - Notifications cleared
2020-09-08 13:14:29,818 - tornado.access - WARNING - 409 GET /api/printer?history=false&limit=0&exclude=sd (::ffff:192.168.1.151) 16.07ms
2020-09-08 13:14:30,806 - tornado.access - WARNING - 409 GET /api/printer?history=false&limit=0&exclude=sd (::ffff:192.168.1.151) 27.92ms
2020-09-08 13:14:31,801 - tornado.access - WARNING - 409 GET /api/printer?history=false&limit=0&exclude=sd (::ffff:192.168.1.151) 22.90ms
2020-09-08 13:14:32,886 - octoprint.util.comm - INFO - Changing monitoring state from "Offline" to "Opening serial connection"
2020-09-08 13:14:32,892 - octoprint.util.comm - INFO - Connecting to port /dev/ttyUSB0, baudrate 115200
2020-09-08 13:14:32,929 - tornado.access - WARNING - 409 GET /api/printer?history=false&limit=0&exclude=sd (::ffff:192.168.1.151) 13.52ms
2020-09-08 13:14:32,961 - octoprint.util.comm - INFO - Changing monitoring state from "Opening serial connection" to "Connecting"
2020-09-08 13:14:32,978 - octoprint.util.comm - INFO - M110 detected, setting current line number to 0
2020-09-08 13:14:33,803 - tornado.access - WARNING - 409 GET /api/printer?history=false&limit=0&exclude=sd (::ffff:192.168.1.151) 25.05ms
2020-09-08 13:14:34,408 - octoprint.util.comm - INFO - M110 detected, setting current line number to 0
2020-09-08 13:14:34,788 - tornado.access - WARNING - 409 GET /api/printer?history=false&limit=0&exclude=sd (::ffff:192.168.1.151) 13.22ms
2020-09-08 13:14:35,802 - tornado.access - WARNING - 409 GET /api/printer?history=false&limit=0&exclude=sd (::ffff:192.168.1.151) 23.83ms
2020-09-08 13:14:36,802 - tornado.access - WARNING - 409 GET /api/printer?history=false&limit=0&exclude=sd (::ffff:192.168.1.151) 23.33ms
2020-09-08 13:14:36,903 - octoprint.util.comm - INFO - M110 detected, setting current line number to 0
2020-09-08 13:14:36,908 - octoprint.util.comm - INFO - Changing monitoring state from "Connecting" to "Operational"
2020-09-08 13:14:36,929 - octoprint.util.comm - INFO - M110 detected, setting current line number to 0
2020-09-08 13:14:36,960 - octoprint.util.comm - INFO - Printer reports firmware name "Marlin SkyNet3D-V2.3.2 (Github)"

Additional information about your setup

OctoPrint : 1.4.2
**Octopi Version 0.16.0, running on Raspberry Pi 3 Model B Rev 1.2
**Anet A8 printer turned into Marlin with skynet v2.3.2

[PrintedWeezl]

[djsixto]

Sorry, it's already completed, the translation into Spanish was not very accurate
regards

[foosel]

OctoPrint randomly loses connection to the printer with a "SerialException"

A "SerialException" like e.g. device reports readiness to read but returned no data indicates that something a layer beneath OctoPrint broke and the connection to your printer was lost due to that. There's nothing OctoPrint can do about this - as already said the issue happens beneath OctoPrint. It's basically like someone pulled the rug from beneath its feet. The most common reasons for this are: You are running OctoPrint on a Raspberry Pi but have not powered said Pi from a good power suppl…

[mguima]

A lot of USB errors started to appear when I replaced an USB cable 4 feet log , with a ferrite bead in one end, for one of those ubiquitous Chinese 1 ft long blue cables, that usually come with Arduino's clones.
I removed the blue cable and reinstalled the good quality one, and suddenly all the errors were gone.