After update i cant connect

Basic Information:

Printer Model: vcore 3.1
MCU / Printerboardoctopus pro + Ebb42
klippy.log (6).txt (5.4 MB)

Fill out above information and in all cases attach your klippy.log file. Pasting your printer.cfg is not needed
Be sure to check our Knowledge Base and in particular this and this post

Describe your issue:


This morning I made a short impression… And at the end I have updated, everything except the Octopus Pro, because it is the 429 and the Ebb42.

Well, after rebooting have come lis problems … Fluidd does not connect to the printer… I guess it will have to do with the update

I can read these error

mcu ‘mcu’: Unable to connect
Once the underlying issue is corrected, use the
“FIRMWARE_RESTART” command to reset the firmware, reload the
config, and restart the host software.
Error configuring printe

There is a method for revert update?

What is everything?

Have you checked that the serial is still valid:

baud = 250000
serial = /dev/serial/by-id/usb-Klipper_stm32f429xx_3A0039000D50304738313820-if00

Have you checked the USB connection?

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If your Pi OS is Debian Bullseye, you’re like affected by this bug.
Follows the instruction on that topic and klipper should be able to connect after a reboot.


No… The lottery won’t touch me… but this.

I read few days ago and believed that it could be produced by updating klipper, and I have not updated klipper, if the rest…

When I get home I’ll try

Same thing happened to me yesterday. There were two problems. As someone else mentioned herein, the USB connection changed. The "serial = " statement had changed. The second problem probably affects only a few users. I have a BME280 hooked up to the PI on I2C 1. The RPI mcu would no longer load. I had to reload the RPI firmware with the make command and reflash.

Afterward, all was well.

i have checked, and that i am affected

the response of:

pi@fluiddpi:~ $ apt-cache policy udev


pi@fluiddpi:~ $ apt-cache policy udev
Installed: 247.3-7+rpi1+deb11u2
Candidate: 247.3-7+rpi1+deb11u2
Version table:
252.5-2~bpo11+1 100
100 Index of /debian bullseye-backports/main armhf Packages
*** 247.3-7+rpi1+deb11u2 500
500 Index of /raspbian bullseye/main armhf Packages
100 /var/lib/dpkg/status

It’s the opposite actually: the bug comes with OS system package updates.

Mainsail crew made a onliner fix:

curl -sSL | bash
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thanks… to all

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