Basic Information: Printer Model: FLSUN Super Racer MCU / Printerboard: Robin Nano V3 klippy-1.log (606.2 KB) I am getting constant MCU Lost Communication errors. Happens at all different times. I have tried to read through the log but it might as well be in Martian. I have been fighting this f…

It is fixed!!! Wiring the pad to power on the 12/24 on the board fixed the problem. It has synced over a thousand times now without an error. Thank you so much for the help!!

I’ve used 10 different cords of varying lengths. All high speed/gold plated high quality cables and nothing changes.

What is your dmesg output on your Klipper host?

[ 3.017652] sunxi-mmc sdc2: sdc set ios:clk 100000000Hz bm PP pm ON vdd 22 width 8 timing MMC-HS200 dt B [ 3.018235] sunxi-mmc sdc2: sdc set ios:clk 100000000Hz bm PP pm ON vdd 22 width 8 timing MMC-HS(SDR20) dt B [ 3.018438] sunxi-mmc sdc2: sdc set ios:clk 52000000Hz bm PP pm ON vdd 22 wid…

[image] Guffanator: usb 1-1-port4: disabled by hub (EMI?), re-enabling… Your host keeps resetting the USB subsystem because of a condition consistent with excessive electromagnetic interference. This is usually caused by poorly shielded USB cables, but it can also be caused by a poor quality …

Only thing connected is the printer. When you say hardware are you referring to the speeder pad or the main board. I ask because before I switched to klipper I had the printer hooked directly to my computer through USB and it would do what I assume is the Marlin equivalent of lost MCU by just stoppi…

If the speeder pad still resets the USB connection like that without anything connected to it, then the problem would most likely be in the speeder pad itself. If the USB resets only occur when the printer (and no other USB peripherals) are connected, then that would suggest that the printer (i.e. t…

Problem with troubleshooting the pad is it doesn’t boot klipper unless it’s connected to the printer. Just says printer is not ready and then says mcu unable to connect.

Can you ssh into it? How did you get the dmesg output?

Super Racer Lost MCU

General Discussion

theophile January 5, 2024, 6:01pm 2

This can usually be fixed by using a new, quality USB cable: Got EOF when reading from device

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Super Racer Lost MCU

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