HELP! Ender 3 4.2.7 mcu 'mcu': Unable to connect Anyone successfully flash the firmware?

General Discussion
1

Basic Information:

Printer Model: Ender 3
MCU / Printerboard: 4.2.7
Host / SBC: Creality wifibox
klippy.log

Describe your issue:

Still unable to connect not sure what to do, just got this 2nd hand printer just wanted to use what is available now.

Already done

  • Successfully flashed openwrt &klipper on to Creality wifibox
  • Confirmed sdcard compatibility by flashing Marlin back on to board
  • Confirmed USB cable by using original Creality cloud to print.
  • Confirmed insulating the power pins of the USB cable
  • Confirmed chip STM32F103 RET6 thus made firmware for atm32f103x6 along with baud 115200
  • Tried connecting from both USB1&USB2 on wifi box
  • Config.cfg using the generic 4.2.7 with [include fluidd.cfg] [include timelapse.cfg]

klippy.log (135.7 KB)

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image1680Ă—746 61.1 KB

…

2

Hello @NEROSIUS

Have you a bit more information on that - like a link?

serial = /dev/serial/by-id/usb-1a86_USB_Serial-if00-port0

How did you obtain that?

3

Here are the most updated links, hope that you can help :slight_smile:

[https://www.youtube.com/watch?v=0y3qt8cvtKY]

got the serial from the config example

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image840Ă—326 13.9 KB

4

Have you ever had a look into the docs? Installation - Klipper documentation

1 Like
5

Yes, but was not sure how to approach it, I just got this 2nd hand printer and came across what I have shared. With the hardware I had, it seems right do a little tweaking from stock.

Learnt how to build the firmware. from WSL and openwrt

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image1112Ă—626 12.8 KB

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image1680Ă—746 13.2 KB

6

If you do a search in the original Klipper documentation Overview - Klipper documentation for “WSL” or “openwrt” you’ll not getting any hit.
I would rethink you approach and start over.

1 Like
8

thanks for the tip. Of course, if at the end it can’t be done will find a new approach. This is only my 2nd week fooling around with the printer.
WSL is Windows Subsystem for Linux
openwrt is only for putting the wifiboc to good use.

9

I guess the Creality Wi-Fi Box came with the printer. To be honest, replace the Creality Wi-Fi Box with an SBC, else you’ll probably waste a lot of time without a good result. Creality is known for not supporting genuine Klipper.
I apprechiate the efforts from shivajiva101 Can not get it to work · Issue #13 · shivajiva101/KlipperWrt · GitHub but the Creality Wi-Fi Box is an old piece of hardware, witch was never officially supported by Klipper. You might also have a look here Possible threading issue in Klippy? - #3 by jakep_82 about the poor performance of the Creality Wi-Fi Box.

1 Like
10

Thanks again, how about if I use a laptop running mint instead of the wifi box and connect to the printer.(Came across it somewhere)The thing is, I’m not sure if the printer board was successfully flashed or not.

11

The error

mcu 'mcu': Unable to open serial port: [Errno 2] could not open port /dev/serial/by-id/usb-1a86_USB_Serial-if00-port0: [Errno 2] No such file or directory: '/dev/serial/by-id/usb-1a86_USB_Serial-if00-port0'

Indicates two things:

  • You did not follow the official instructions, which always require verifying the path with ls /dev/serial/by-id/*.
  • The board is not correctly flashed, or the Linux box is unable to enumerate the board as a USB device.

When it comes to OpenWRT, Android, or some other esoteric approaches:

  • I do not care about these, nor do I read or check such guides.
  • Klipper’s recommendation is a dedicated SBC with a headless Debian or Debian-like OS.
  • If anything else is used, it is assumed that enough Linux administration skills are present to handle any potential issues or unexpected behavior.
1 Like