Mcu 'mcu': Unable to connect after Sep 17 klipper update

General Discussion
1

Basic Information:

Printer Model: Ender 3 Pro
MCU / Printerboard: BTT SKR 3 + EBBCAN with U2C
Host / SBC: Raspberry Pi 5
klippy.log (636.2 KB)
moonraker.log (669.6 KB)

Describe your issue:

Printer was printing ok on Sunday 15. After it finished the print, I updated Klipper (don’t remember if other component too). I always maintain the componentes up to date, so this wasn’t a big jump in versions.
The Rpi is connected via USART (ttyAMA0) to the mcu (TFT connector).

Now I turn on the Machine and I can’t connect to the MCU. I tried making the bin files for the MCU and for the EBBCAN and reflash them, but that does not solve the issue.
I tried roll back to 2, 5, 10, 15 and 100 Klipper and Moonraker versions, regenerating bin files, and reflashing. And that does not solved the issue.

I literally didn’t change anything else!

has anyone any idea what could it be? I Don’t want to waste time setting up the whole klippler, rpi, mcu, etc. if I have no guarantee that the issue will be solved!

Edit:
I did a full new instalation (Pi OS image, kiauh, klipper, moonraker, EBBCAN, U2C, Mainboard, etc.) and I am having the exact same issue and logs. I Suspect it has something to do with klipper. Just in case it is HW related, I will try to flash FW to conect via USB instead of Serial.

Edit 2:
I tested the Pi UART Tx and Rx by shorting them together and then sending a message. and the message arrvide, so it is not a HW problem on the Pi side.
I made a new communication cable, and that didn’t solve anything
I bought a new skr 3, and that didn’t solve anything.
At this point I’m 100% sure it is a firmware/software issue

2

When you updated to a genuine new Klipper version, it should not be dirty:

Git version: 'v0.12.0-286-g81de9a861-dirty'
3

yep, no idea how that happend. But before the update I am 100% sure I didn’t change anything in klipper per se. I only work on the cfg files.

4

I used to have “dirty logs” because of an added Makefile, you should move any custom files outside the repo root and avoid changing permissions, like I used to do:

chmod +x ./klippy/klippy.py

If that’s the case, you’ll have to run klippy via python:

python ./klippy/klippy.py [...]
5

I never added makefiles nor changed the permissions! no idea what happend.

I will try to run klippy via python, if that doesn’t work, I will try to reinstall everything

6

I checked and it is “dirty” because I installed G-code shell command via Kiauh, it says that right in the line below where it states the Klipper version…