Ender 3 Octoprint not connecting

[DerMannheimer]

Hi community,

Although there are countless entries about the Octoprint and Ender 3, I still don't get my problem solved and therefore ask for your help. PLEASE!

I use a Creality Ender 3 and have already been able to print successfully with it. Now I wanted to connect a Raspberry Pi 3 and print a little more comfortably via Octoprint.

The setup of the Raspberry Pi seems to have worked well. I was able to flash it and I can also access the Pi via PuTTY. I updated the Pi accordingly. All of this worked fine over WiFi. I was also able to set up Octoprint and I can also access the Raspberry Pi via Octoprint.

I then connected the Pi to the Ender 3 using a USB cable, but unfortunately no connection is possible. The settings are on "AUTO". No port can be selected. I tried all of the baud rates without success.

The printer says it is running with Marlin 1.0.1 if this might be important.

I am using a proper power supply and there is no warning shown in Octoprint.

Can someone tell me what to check next? Do i need to check the log files or did i miss something obvious?

[Ewald_Ikemann]

Hello @DerMannheimer !

Moved it because it's not a network issue.

Yes logs are mandatory. In this case most important is the serial.log.
You may have to enable the serial logging before.

Where can I find OctoPrint's and OctoPi's log files?

To help with problem analysis, it's important to share relevant log files. This FAQ entry is going to tell you where to find the log files of the OctoPrint application and the OctoPi OS image. Confused about OctoPrint vs OctoPi? Read this FAQ entry on the difference between the two. OctoPrint All log files that OctoPrint writes can be found in the logs sub folder in its configuration directory: on Linux: ~/.octoprint/logs on Windows: %APPDATA%\OctoPrint\logs on MacOSX: ~/Libr…

[DerMannheimer]

Sorry and thanks for moving!

[Charlie_Powell]

Try several different USB cables. The Pi is not detecting a printer at all.

If it helps you, plug it in to a PC so you can see the notification/sound when you plug something in. If the PC does not see it, try a different USB cable. When you find one that works, and you can recognise the printer as a device try connecting it with OctoPrint. When you plug the printer in again press the 'refresh' icon besides the connection options to get the most up to date list.

[DerMannheimer]

serial (3).log (1.8 KB)

Here you go with the serial.log - i honestly cant figure anything out of it

2021-04-07 20:56:55,422 - Changing monitoring state from "Offline" to "Detecting serial connection"
2021-04-07 20:56:56,160 - Performing autodetection with 0 port/baudrate candidates:
2021-04-07 20:56:56,161 - Changing monitoring state from "Detecting serial connection" to "Error: No more candidates to test, and no working port/baudrate combination detected."
2021-04-07 20:56:56,162 - Changing monitoring state from "Error: No more candidates to test, and no working port/baudrate combination detected." to "Offline (Error: No more candidates to test, and no working port/baudrate combination detected.)"
2021-04-07 20:57:26,098 - Changing monitoring state from "Offline" to "Detecting serial connection"
2021-04-07 20:57:26,136 - Performing autodetection with 0 port/baudrate candidates:
2021-04-07 20:57:26,137 - Changing monitoring state from "Detecting serial connection" to "Error: No more candidates to test, and no working port/baudrate combination detected."
2021-04-07 20:57:26,139 - Changing monitoring state from "Error: No more candidates to test, and no working port/baudrate combination detected." to "Offline (Error: No more candidates to test, and no working port/baudrate combination detected.)"
2021-04-07 20:57:30,240 - Changing monitoring state from "Offline" to "Detecting serial connection"
2021-04-07 20:57:30,289 - Performing autodetection with 0 port/baudrate candidates:
2021-04-07 20:57:30,290 - Changing monitoring state from "Detecting serial connection" to "Error: No more candidates to test, and no working port/baudrate combination detected."
2021-04-07 20:57:30,292 - Changing monitoring state from "Error: No more candidates to test, and no working port/baudrate combination detected." to "Offline (Error: No more candidates to test, and no working port/baudrate combination detected.)"

[DerMannheimer]

Oh my freakin god.. YOU Sir, are an absolute genius and i am ashamed.. Although i already used two different usb cables before posting (they both DO work on other devices!!) and connected them in various slots on the pi, i now just used a third usb cable for gods sake and i can not believe it suddenly started working..

The both non-working cables do still work for connections to my computer as well as charging and data transfer to other devices. Somehow my Ender just won't accept them.. I can not explain this but i'm happy its finally solved after weeks..

Thanks a lot!