Basic Information:
Printer Model: Single Extruder Sovol SV04
MCU / Printerboard: BTT Octopus V1.1
Host / SBC BTT Pi
klippy.log (551.8 KB)
Fill out above information and in all cases attach your klippy.log file (use zip to compress it, if too big). Pasting your printer.cfg is not needed
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Describe your issue:
…
I have been having this mcu.error: Can not update MCU 'mcu' config as it is shutdown error popping up at random times during a print. Sometimes it happens 10 hours in to a print other time 2 hours or even 10 minutes. It happens on several different print files also. I have tried to reflash the MCU firmware multiple times using the manual from BTT as a guide, I have swapped the Mainboard with a new BTT Octopus V1.1 board. I have tried a new power outlet along with a new power bar. Nothing I have done seems to make a difference. I have rolled back the log files and used the FIRMWARE_RESTART command prior to starting my last test print when the error presented itself again. The Klippy.log file I included is from immediately after the error showed up.
Could it be a problem with the BTT Pi that is causing this issue?
I have ran out of ideas on how to fix this persistent error any help would be appreciated.
Thanks
You’re running a modified version of Klipper. It looks like you have a lot of untracked “addon” files related to a MMU and “dynamic macros.” Try again with a clean codebase and see if the problem persists.
@theophile
I have Reinstalled a clean version of klipper but unfortunately the error is persisting. I have included the new Klippy.log file
klippy_Clean.log (238 KB)
@Sineos
This is an unhelpful answer I have repeatedly ran the FIRMWARE_RESTART command after this notification and it still continues to produce this. I understand that it is not necessarily and error more of a notification of the disconnect, But what would cause the disconnect without reporting anything in the klippy.log file? There has to be a reason for the disconnect. Its not like I’m purposely unplugging the USB cable 10 hours into a print.
I’m not positive, but my money is on connection problem between the host and the MCU. In both logs the error shows up while trying to process the MCU config.
On your host, ssh into the system after an error like this and check your dmesg output for any signs of USB connection/reconnection or any other messages that might have been generated around the same time.
Both logs showed something caused a full restart of the Klipper host process.
Stats 3054.0: gcodein=0 mcu: mcu_awake=0.005 mcu_task_avg=0.000007 mcu_task_stddev=0.000006 bytes_write=27553 bytes_read=119981 bytes_retransmit=9 bytes_invalid=0 send_seq=1971 receive_seq=1971 retransmit_seq=2 srtt=0.001 rttvar=0.000 rto=0.025 ready_bytes=27 upcoming_bytes=0 freq=180003041 sd_pos=59245 Octopus: temp=30.1 BBT_Pi: temp=46.2 heater_bed: target=60 temp=60.3 pwm=0.385 sysload=1.85 cputime=13.727 memavail=567872 print_time=646.393 buffer_time=0.000 print_stall=0 extruder: target=150 temp=150.0 pwm=0.136
Starting Klippy...
Args: ['/home/biqu/klipper/klippy/klippy.py', '/home/biqu/printer_data/config/printer.cfg', '-I', '/home/biqu/printer_data/comms/klippy.serial', '-l', '/home/biqu/printer_data/logs/klippy.log', '-a', '/home/biqu/printer_data/comms/klippy.sock']
Git version: 'v0.13.0-124-g018102395-dirty'
Untracked files: klippy/extras/dynamicmacros.py, klippy/extras/mmu_encoder.py, klippy/extras/mmu_espooler.py, klippy/extras/mmu_led_effect.py, klippy/extras/mmu_leds.py, klippy/extras/mmu_machine.py, klippy/extras/mmu_sensors.py, klippy/extras/mmu_servo.py
Branch: master
Remote: origin
Tracked URL: https://github.com/Klipper3d/klipper
CPU: 4 core ?
Python: '3.11.2 (main, Apr 28 2025, 14:11:48) [GCC 12.2.0]'
Start printer at Thu May 29 10:24:51 2025 (1748535891.6 3065.5)
And:
Stats 2337.8: gcodein=0 mcu: mcu_awake=0.005 mcu_task_avg=0.000009 mcu_task_stddev=0
.000009 bytes_write=291203 bytes_read=160262 bytes_retransmit=9 bytes_invalid=0 send_
seq=8832 receive_seq=8832 retransmit_seq=8 srtt=0.001 rttvar=0.000 rto=0.025 ready_by
tes=0 upcoming_bytes=0 freq=180002900 sd_pos=73299 Octopus: temp=32.0 BBT_Pi: temp=45
.6 heater_bed: target=60 temp=60.0 pwm=0.112 sysload=1.07 cputime=16.506 memavail=560
456 print_time=357.749 buffer_time=2.318 print_stall=0 extruder: target=205 temp=205.
1 pwm=0.286
Starting Klippy...
Args: ['/home/biqu/klipper/klippy/klippy.py', '/home/biqu/printer_data/config/printer
.cfg', '-I', '/home/biqu/printer_data/comms/klippy.serial', '-l', '/home/biqu/printer
_data/logs/klippy.log', '-a', '/home/biqu/printer_data/comms/klippy.sock']
Git version: 'v0.13.0-133-g8d7e48714'
Branch: master
Remote: origin
Tracked URL: https://github.com/Klipper3d/klipper
CPU: 4 core ?
Python: '3.11.2 (main, Apr 28 2025, 14:11:48) [GCC 12.2.0]'
Start printer at Sat May 31 06:45:39 2025 (1748673939.1 2349.4)
Unfortunately, the log does not contain information on what caused that external restart. Make sure you aren’t clicking on any web page buttons that could be causing a restart (if applicable) and make sure there aren’t any loose wires, loose touchscreen installations, or similar that could be accidentally commanding a restart (if applicable). Otherwise, another option may be to perform a full OS reinstall of the host computer.
-Kevin