Ender 3 V2 - Linux Machine - NO MCU FOUND

Basic Information:

Printer Model: Ender 3 V2
MCU / Printerboard: 4.2.7
klippy.log

Fill out above information and in all cases attach your klippy.log file. Pasting your printer.cfg is not needed

Describe your issue: I recently installed klipper on my ender 3 v2, and installed linux on a laptop to run klipper, installed using KIAUH. It ran and worked perfectly on the laptop, but i need the laptop so i bought a cheap DELL 3050 to have it running 24/7. Although now no matter what I do i cant get the MCU to be found.

I have uninstalled and reinstalled klipper, moonraker, mainsail multiple times, and have flashed firmware on ender again just to make sure, even though it connect to laptop fine. Tried every USB port on dell, as well.
Any tips? Thanks!

Try following approach:

  1. Disconnect your MCU from the DELL
  2. Reconnect
  3. Run sudo dmesg
  4. Check if and how the USB device is registered
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Thanks for the response! This is the message i get, doesnt show klipper or anything. If it helps i can unplug it from dell and plug into laptop and it works right away.

Try the following:

 sudo systemctl list-units | grep brltty

It should give a list of brltty related services. For each item in the list run

sudo systemctl mask brltty.path
sudo systemctl stop brltty.path

brltty.path is just an example. Replace it by the output of the first command.

Then unplug and replug your board.

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Thank you so much! Did exactly that and its working!

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Made an account just to say THANK YOU!!

I’ve looked into replacing my Pi with a NUC and this part was stumping me.

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Good Afternoon Sineos,
I have a similar issue and get the same results and post shown above, Hoping you can help on this one. You mention changing the brltty.path, where would I get this exactly as everything I’ve tried doesn’t seem to have worked. I did the install as stating and ensured to select the following settings

"This file contains pin mappings for the stock 2020 Creality Ender 3

V2. To use this config, during “make menuconfig” select the

STM32F103 with a “28KiB bootloader” and serial (on USART1 PA10/PA9)

communication."

The only address I get it ttyS0.

Thanks in advance

my exactly reply when typing in the command you mentioned it -
brltty-udev.service loaded active running Braille Device Support

I got an address however it states permission denied, is there away to give permission to allow access to the port /dev/serial/by-id/usb-1a86_USB_Serial-if00-port0: Permission denied

Please post the output of

sudo systemctl list-units | grep brltty

just had a firmware upgrade, now when trying sudo systemctl list-units | grep brltty I don’t get anything back. Previously I did however get back - /dev/serial/by-id/usb-1a86_USB_Serial-if00-port0: Permission denied. When i got back in to klipper and try getting the MCU ID from that I get nothing on USB and UART I get muc #1: ttyS0

As it happens I just happen to re run sudo dmesg and got a massive feed with alot of “DENIED” this seems to have happened after a firmware update. I’ve attached a copy rather than pasting it directly in here due to the size of it
Sudo dmesg.txt (88.1 KB)

one that stood out in Red Font - [Firmware Bug]: No firmware reserved region can cover this RMRR [0x000000009d800000-0x000000009fffffff], contact BIOS vendor for fixes, however I believe this on used for widows and not needed for linux, although I’m still learning the system. I would certainly move to linux over windows if it wasn’t for gaming

audit: type=1400 audit(1679334474.949:42): apparmor="DENIED" operation="capable" class="cap" profile="/snap/snapd/18357/usr/lib/snapd/snap-confine" pid=965 comm="snap-confine" capability=12 capname="net_admin"

If you are referring to this, I would not consider this a problem. Could be, but my knowledge about apparmor is limited.

From the dmesg output no trace of a printer board is found. Try

  1. Disconnect your MCU from the PC
  2. Reconnect
  3. Run sudo dmesg
  4. Post the results

Hi, Thanks for getting back to me, as it happens I tried all that and wasn’t getting anywhere, as it was a barebone install, I thought it would be best to reinstall the OS and then complete the klipper install via Kiauh, hopefully get back to where I was. I did manage to get to the MCU ID, how it was stating Permission Denied, hopefully if I get back to that stage they will be away around access that permission. I’ll keep you posted, shouldn’t take that long. Thanks again for your help. It’ll all be worth time for me in the future :slight_smile:

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Maybe just start a new thread before continuing here.

thanks, I can see your very active on a number of forums, so I do appreciate your time. Thanks will do

Hi Sineos, sorry to bother you, i cant figure out why my MCU says not found can you please help me, im using raspberry pi 3 b+ and trying it on a ender 3 s1

if tried using the comments ive seen here but it doesnt help

ssss.txt (30.6 KB)

Can you at least post the klippy.log ?

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A post was split to a new topic: SKR3 EZ - No MCU serial