Basic Information: Printer Model: Voron 2.4 350 MCU / Printerboard: Fysetc Spider v3 Host / SBC: rpi4 MODEL b klippy.log Hello, I have random freezes ( rpi not respont/no ssh/ klipperscreen freeze) and random lost connection to Mcu. Sometimes it happens after 3hrs or 30 min during the prin…

Your description sounds like a hardware stability issue on the Linux/RPi level. Potentially caused by additionally attached hardware. The dmesg output points to an issue with the Wi-Fi adapter, but this is not necessarily the root cause.

I had an another disconnect, now with the wifi turned off. brcmfmac: brcmf_set_channel: set chanspec 0xd0a5 fail, reason -52 the changes I made: turned off wlan power saving added over_voltage=2 to boot config

Hi I tried and have the same issue. I removed all the USB from the pi (except the MCU) and it made it even worse, it is not connecting at all anymore. After I tried to update the mcu firmware to the latest version - no success then I tried to reinstall everything from scratch - still can’t connec…

[image] kenny0011: I’m fairly sure it’s a software issue Your dmesg output unlikely is a software issue, at least not one related to Klipper.

I think I found the cause of the issue. the fysetc hardware button put the main MCU in a connect/disconnect loop. anyone have an idea how to troubleshoot this?

Random freeze/ lost connection to MCU

General Discussion

Sineos April 14, 2025, 3:33pm 4

Just as a long shot: Try Raspberry pi freezes completely if rebooted while mainboard is kept powered - #6 by Sineos

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Random freeze/ lost connection to MCU

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