Ender 3 skr mini e3 V3 not connecting

[Andrejs_Pidjass]

What is the problem?

Octoprint can't connect to Ender 3 with SKR mini E3 V3. Interesting that I'm able to see my files on SD card despite printer offline state.

What did you already try to solve it?

Tried 5 different cables, Unchecked "Request exclusive access to the serial port" in the OctoPrint settings menu.

Have you tried running in safe mode?

Yes

Did running in safe mode solve the problem?

no

Systeminfo Bundle

2022-05-20 20:22:59,743 - octoprint.util.comm - ERROR - Unexpected error while reading from serial port
Traceback (most recent call last):
  File "/home/pi/oprint/lib/python3.7/site-packages/octoprint/util/comm.py", line 3992, in _readline
    ret = self._serial.readline()
  File "/home/pi/oprint/lib/python3.7/site-packages/octoprint/util/comm.py", line 6667, in readline
    c = self.read(1)
  File "/home/pi/oprint/lib/python3.7/site-packages/serial/serialposix.py", line 596, 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?)
2022-05-20 20:22:59,745 - octoprint.util.comm - ERROR - Please see https://faq.octoprint.org/serialerror for possible reasons of this.
2022-05-20 20:22:59,754 - octoprint.util.comm - INFO - Changing monitoring state from "Operational" to "Offline after error"

Additional information about your setup

Raspberry Pi4
Octoprint OctoPrint 1.8.0
Ender 3
Skr mini e3 V3
Marlin 2.0.X bug fix

[Ewald_Ikemann]

Hello @Andrejs_Pidjass !

It's the weirdness of Creality firmware.

Try this:

Put tape on the 5V pin - Why and how

First of all this whole tutorial isn't a mandatory mod - you just need it if you run into issues (weird things are happening and you've already ruled out the more common suspects) or if the always running fan and illuminated display (even when the printer is turned off) disturbes you. I'm starting with the why part: If you connect a 3D printer via USB to your Raspberry Pi it can lead to all sorts of power related issues. Most of the time those issues occur only if you turn on your pi before …

Also try without SD card in the printer's SD card slot.

[Andrejs_Pidjass]

Never thought that a little piece of tape could solve that problem. Thank you so much! Now it connects flawlessly. Should I consider to update a firmware or it's better not to touch anything if it works for now?

[Ewald_Ikemann]

As long you know to workaround that flaw and it works well, it is ok.

3rd party firmware can be a solution to, sure.