So I just recently got and assembled my Ender 3. And then I got a data compatible cable to plug into my raspberry pi and the device does show up on OctoPi but I cannot actually interact with the device from octoprint nor does the device change to operational in the status bar
Additional Info:
As of the time of posting this I am running,
Latest version of Marlin for Ender 3 (Sourced from Creality) I have however tried running octopi with stock firmware and the same issue occured
Raspberry Pi 3: Latest version of OctoPi on Stable channel
The cable I am using is from a logitech mouse, however I can confirm that it is capable of transfering data very well
Serial communications with Creality printers (including the Ender 3) have often been problematic. Enabling the serial.log is going to be helpful.
The uploaded bundle shows env.plugins.pi_support.throttle_check_enabled: False which is not a good idea at this stage. If you are experiencing undervoltage this may be a contributing factor.
EMI can also prevent serial (USB) connections from functioning, and it sometimes requires using many different data enabled USB cables until one that works is found. In most cases, a shielded cable with ferrite cores and careful routing is needed. You can search this forum for numerous topics on this subject.
Please enable the serial log and the throttle check, attempt to connect to the printer again, and upload another bundle.
Okay. I fixed my Throttling issue by plugging into a less sketchy outlet. So I fixed throttling
Also here is my log. But what is EMI and how do I fix that?
Interesting... There's no serial.log in the bundle. I always thought it would be there either as the real thing or the one that says it is not enabled.
Good News... There is a serial log in this latest bundle.
Bad News... The contents of the log:
2025-03-08 15:21:37,605 - Enabling serial logging
2025-03-08 15:35:11,008 - Disabling serial logging
Please reenable the serial log.
Can you SSH into the RPi? If so, then please enter the following steps and then upload the output here using the </> tool above.
Type sudo dmesg --clear
Unplug the printer and turn it off.
Plugin the printer and turn it on.
Type dmesg and copy the output here.
Type lsusb and copy the output here.
This will verify that the operating system (OctoPi) sees the printer which is required if OctoPrint is going to connect to the printer. It will also tell us what the serial device name is so we can make sure OctoPrint is looking in the right place.
I'm not sure how to copy / paste from the Linux SSH terminal to the MacOS so you may have to search the internet for instructions. On Windows using PuTTY, you just highlight the text using the left mouse button and the ctrl-V into this window.
Alright. Just a heads up I was printing from SD card while following steps so if you think that is affecting the results then I will try again later but here are the results
Dmesg:
[ 166.369856] usb 1-1.4: new full-speed USB device number 5 using dwc_otg
[ 166.502744] usb 1-1.4: New USB device found, idVendor=1a86, idProduct=7523, bcdDevice= 2.64
[ 166.502776] usb 1-1.4: New USB device strings: Mfr=0, Product=2, SerialNumber=0
[ 166.502792] usb 1-1.4: Product: USB Serial
[ 166.503655] ch341 1-1.4:1.0: ch341-uart converter detected
[ 166.505873] usb 1-1.4: ch341-uart converter now attached to ttyUSB0
Lsub:
Bus 001 Device 003: ID 0424:ec00 Microchip Technology, Inc. (formerly SMSC) SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 002: ID 0424:9514 Microchip Technology, Inc. (formerly SMSC) SMC9514 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
The dmesg output shows that it saw the printer and it is device /dev/ttyUSB0.
It didn't show up on the lsusb output but you might try again now that it works just so we can see what it should look like.
You asked earlier about EMI, ElectroMagnetic Interference so here is a link that explains what it is. If you search this forum for EMI you will find lots of topics and some of the symptoms and some of the solutions.
We don't know if you will have any EMI issues until you do some printing through OctoPrint, so we'll cross that bridge if we come to it.
Awesome. Well thanks for all of the help. I will try printing something through octoprint to see if the issues occur because I know for sure that I do have other cables. But also should I mark anything as a solution or just leave it at this as the issue was self-resolved as far as we know.
