Basic Information [CR6-Max] Printer Model [stm32f103xe] MCU / Printerboard klippy.log (1.8 MB) klippy log Describe your issue: It recently started without me knowingly changing something (altough as you can see from the logs I only have Klipper since a month or so and was just about to tune input…

Thanks for the suggestions but I tried a lot of those things already Now I also tried: Unplugging everything except the one USB to the printer Stress testing the Laptop to make sure it’s not underpowered It worked fine for a couple of hours and now the same error accured again. Of course both US…

Unfortunately I do not know of any more reasons that already given in the link above and typically it is one of them. The laptop is delicately running Klipper and not any virtual machine / WLS additional things?

It is ubuntu with gui and I use it for spotify youtube and so on. But while testing I dont. Maybe I need to try the cut wire trick on the usb cable… Or maybe theres something in ubuntu that puts the usb to sleep?

Did log the USB and got the following: [ +0.227356] usb 1-1.1: new full-speed USB device number 8 using xhci_hcd [ +0.101286] usb 1-1.1: New USB device found, idVendor=1a86, idProduct=7523, bcdDevice= 2.64 [ +0.000005] usb 1-1.1: New USB device strings: Mfr=0, Product=2, SerialNumber=0 [ +0.000…

[image] Smoothy: [ +0.034002] usb 1-1-port1: disabled by hub (EMI?), re-enabling... When it is random, EMI comes to my mind.

So try a better shielded cable?

Yes. If there are high power devices near by, like ACs etc, you also may block the power cords. EMI is quite a complex area. Lot of things can cause issues.

I’m not sure, but it sounds like you’re not using a single board computer like a Raspberry Pi to run Klipper on but a Microsoft Surface PC running Ubuntu - is this correct? If that’s the case, then the issue is most likely caused by the OS software performing periodic high priority tasks like garba…

Also take care, that the USB cable does not get too close to the steppers and their cables.

Random MCU communication errors

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Sineos March 1, 2023, 3:29pm 2

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