MCU disconnects after about an hour of printing

General Discussion
1

The issue only occurs on RPi CM4, but not on RPi 4B with the exactly same config and slicer settings.

The printer board is BTT SKR3 EZ, there’s nothing relevant in the log right until “received EOF” and “MCU disconnect” messages from what I can tell. Is there anything I could try to diagnose the issue further?

klippy.log (1.8 MB)

2

The issue seems to be fixed after switching to the native UART interface of CM4 (on the 4B-compatible pin header) for communication with printer
Apparently, something’s going on with either CM4 USB stack or USB layout on the expansion board (Raspberry Pad 5 by BTT)