Basic Information: Printer Model: Ender 3 MCU / Printerboard: BTT SKR 3 EZ, EBB36 v1.2, Raspberry Pi 4 klippy.log (6.0 MB) Describe your issue: I keep getting the “Lost communication with MCU ‘mcu’” midway through a print. It’ll usually print for at least 30 minutes before Klipper reports: SH…

I was able to track down what the issue was. Even though I could not possibly imagine how it could be a hardware issue because the prints always failed roughly an hour in, I admit I was wrong, and it was one of the issues @Sineos linked above. It was a bad power supply, or more specifically, a pow…

Refer to Timeout with MCU / Lost communication with MCU Unfortunately, this error is hard to come by, as it can be difficult to find the root cause. Almost 100% surely the problem is somewhere in your hardware.

Might this be relevant? [image] Debian 11 (Bullseye) udev bug - No board or serial found Knowledge Base Background In recent updates, Debian Bullseye (Debian 11) introduced a bug in udev that causes the command ls /dev/serial/by-id/* to fail, because the bug …

No, this issue would cause the board not to connect at all via /dev/serial/by-id but not to drop an existing connection.

I admit I don’t know what host the Ender3 uses (just that it is nominally Open Src) Its just that my Voron always works from a power on. However, if you make any changes such as change a config and do Firmware Restart (it sometimes dies until re-power) or hit the software Red Button and select Reb…

Some additional information: I have everything setup using a USB to CANbus bridge, so the Pi 4 is connected to the SKR via USB, and the EBB36 is connected to the SKR 3’s CAN FD pins. The error is always Lost communication with MCU 'mcu', so the issue has to be between the Pi 4 and the SKR 3, corre…

I don’t know if anyone has ever tried it but there is an SPI to canbus for the Arduino. [image] Arduino CAN Tutorial - Interfacing MCP2515 CAN BUS Module with Arduino In this MCP2515 Arduino based CAN tutorial we will look into the basics of CAN communication protocol and then finally we…

Ender 3: Lost communication with MCU 'mcu'

General Discussion

JassMan23 December 1, 2023, 11:33am 4

Might this be relevant?

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Ender 3: Lost communication with MCU 'mcu'

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