G’day All, I ran into something in the last couple of days that doesn’t seem to be well documented - CanBus on 64 Bit Pi OS’s, eg Bullseye, is highly error-prone. My HW: SKR v2 → Pi 3B+ → U2C → EBB36 Context: I was running an old version of MainSali OS and needed to start a fresh OS build to updat…

I’ve had a few problems with running the rPi’s Mainsail OS. Before you start writing up a ticket, could I suggest that you repeat the experiment with the basic rPi 32bit OS Lite and rPi 64bit OS lite with Klipper/Moonraker/Mainsail/Katapult (if used) installed using KIAUH?

Howdy, yes I can definitely do that. It’ll likely take me a week or so before I’ll have the time. Now that I’ve got my little printer working, I need to finish configuring and tuning a Magneto X for my son’s school. These things are very cool, and so darn big I have to keep it in my garage! :rofl: …

That is a well written guide, perhaps the OS issue should be called out more prominently?

By which I mean the official Klipper wiki - there’s no mention of 32 Bit vs 64 Bit being a potential issue, even in the troubleshooting section: https://www.klipper3d.org/CANBUS.html The reason I raised the issue here, is I couldn’t find a single location that mentioned it via Google, including on…

I do not think it is a general problem, but it might be a problem. Such a pointer would be suited for CANBUS Troubleshooting - Klipper documentation (it briefly already mentions Kernel woes). Feel free to raise a pull request to amend the documentation :wink: [image] dJOS_500: The reason I rai…

@dJOS_500 , I see you call out using an RPI 3B+. Have you tried an RPI 4 or 5 to ensure it is not an issue of overtasking 3B+ with the 64-bit RPIOS? We need more information before we point to the OS or RPI processing speed, memory, USB, etc… debugging requires removing components in the setup to dr…

[image] NAPCAL: Have you tried an RPI 4 or 5 to ensure it is not an issue of overtasking 3B+ with the 64-bit RPIOS? The CPU utilisation was never above 25%, and everything looked pretty normal, aside from the errors in data transmission on the CanBus to the EBB36 MCU. The only other issue I …

I would suggest changing out your U2C V1.x for a V2.x. The V1.x F072 seems slow to push the CAN bus at fast speeds. Note that the U2C is a USB to CAN bus adaptor and is not a Klipper device so it wouldn’t be included in Klipper load information.

[image] NAPCAL: I would suggest changing out your U2C V1.x for a V2.x. The V1.x F072 seems slow to push the CAN bus at fast speeds Considering Klipper and all of the extensions I use appear to be native 32 Bit code, and most Pi’s have less than 4GB of ram, there’s really no good reason to use…

PSA: CanBus on 32 Bit vs 64 Bit Pi's - "Communication timeout" errors

General Discussion

Sineos August 18, 2024, 7:34am 4

This is known and at least briefly mentioned here: Installing Klipper with KIAUH

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PSA: CanBus on 32 Bit vs 64 Bit Pi's - "Communication timeout" errors

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