Basic Information:
Printer Model: klipper Flying bear ghost/voron (DIY) coreXY
MCU / Printerboard: BIGTREETECH Octopus Pro V1.1 STM32H723, toolhead: BTT SB EBB 2209 CAN (stm32g0b1), mmu: MELLOW Easy BRD V1.2 (rp2040)
Host / SBC Raspberry pi 3b+
The last print was started at 12:05 and almost 3 hours later at 2:56 there was an error
klippy.log
CAN adapter Fysetc UCAN
ОС: Debian GNU/Linux 11 (bullseye)
MainsailOS 1.3.2
klipper v0.12.0-85-gd785b396a-dirty
On newer versions and manual installation I have problems with the CAN bus
CAN: bitrate 1000000 and buffer 1024
Describe your issue:
When printing after 3-5 hours the error MCU ‘EBBCan’ shutdown: Timer too close appears.
This often indicates the host computer is overloaded. Check
for other processes consuming excessive CPU time, high swap
usage, disk errors, overheating, unstable voltage, or
similar system problems on the host computer.
Once the underlying issue is corrected, use the
“FIRMWARE_RESTART” command to reset the firmware, reload the
config, and restart the host software.
Printer is shutdown
From the documentation of the user Sineos I was able to make the graphs
klippy (10).zip (1.5 MB)
other graphs.zip (151.4 KB)
on other versions of klipper there were many errors on can line which appeared after about 15 minutes of printing with the error ‘Missed scheduling of next digital out event’ tried to change bitrate and buffer did not help so I installed mainsailos as in the old days with the old version of klipper v0.12.0-85 became better and as I wrote above the problem “Timer too close” which I can not solve in any way.
Generally see: Timer too close
From the log you attached and the fact that you have a rising bytes_invalid counter, some additional potential reasons are:
- Old, defective firmware on the CAN adapter
- Old, defective kernel on the Linux SBC. It should be a kernel version >= v6.6, as previous versions may suffer from a serious CAN bug.
- Your buffer size is much too high and exceeds the recommended value of 128.
1 Like
on newer Linux and klipper version I had error b’Got error -1 in can write: (105)No buffer space available’ already after 15 minutes of printing now kernel v6.1.21-v8+ on many tips from the Internet recommended to set buffer 1024 partially to me it improved the situation and the error became not after 15 minutes but after several hours. The adapter is really old I will try to use my Octopus as a CAN bridge
To put it simply: They are wrong.
The message
Got error -1 in can write: (105)No buffer space available
is a warning and not an unrecoverable error. Klipper will attempt to recover from this.
A rising bytes_invalid counter is a serious error and is typically caused by outdated firmware on the CAN adapter or kernel versions below v6.6. This issue cannot be recovered.
I just had this same issue I was using octopus pro 1.01 and ebb36 v1.2 after starting over from the beggining I set the buffer to 128 and used a 32bit raspberry pi light and my printer worked just fine. A look around the internet reports that this has been a common fix on many can bus network related to klipper.
Partially helped: switching to 32 bit system raspberry pi OS Lite (Bookworm) with kernel version 6.12.25 and also set CAN speed 1000000 and buffer 128. At the end of today’s 5 hour printing there were no problems, but in the settings menu among mcu one of them typed 2930 bytes_invalid in 5 hours, namely mcu MMU (rp2040).
Also updated the Fysetc UCAN Adapter to the latest supported candlelight firmware (68df7d5 1/3/21)
Also for now, I will try to set a longer print overnight (without plastic, of course, while shorting the sensors).
klippy (13).log (7.9 MB)
Unfortunately, I’ve got another error.
