'mcu': Unable to connect`

General Discussion
1

Basic Information:

Printer Model: Ender 5 with CR-Touch
MCU / Printerboard: Creality 1.1.5
klippy.log

Describe your issue:

Hello, all of you. I’m a native German speaker so I hope you can decipher my text.

First this is a modded Ender 5 where I had to flash the bootloader. After that was done i can flash the Klipper firmware onto the mainboard. That all went smooth after short time with Arduino ISP.

make flash doesn’t work so i did the flash with
avrdude -p atmega1284p -c arduino -b 115200 -P /dev/ttyUSB0 -U out/klipper.elf.hex
ill upload a screenshot with my menuconfig. And the flash.

My error is that it takes some time for the connection. After all, it errors out with mcu 'mcu': Unable to connect every time.

image
image657×1083 36.6 KB

klippy (3).log (17.1 KB)

2

Most likely, the flash process was not working properly:

  1. Make sure it is really a V.1.1.x board
  2. Install the bootloader, e.g. according to Ender 3: How to install a bootloader and update firmware - YouTube
  3. Build the firmware for atmega1284p leaving all other options default
  4. Flash with make flash FLASH_DEVICE=/dev/serial/by-id/USB-1a86_USB2.0-Serial-if00-port0
3

Thank you for your guideline. I actually followed this video prior to flash my bootloader.
Same result.

4

I’d recommend doing it again.
It is ages ago since I last use some 8bit boards, so my memory might not be accurate but with a proper bootloader the make flash should work.

Also, I vaguely remember that using avrdude to actually flash the application has some strange limitations:

  • You would need to use the -D flag to prevent overwriting the bootloader (full chip erase)
  • Even with this flag this will only work once, since these chips do not support partial erase

The above is to be taken with caution, since it is a long time ago since I last worked with such boards.

5

thanks Sineos.

Current State:
For now, I flashed Marlin again. All fine. So I think there´s something with the connection method. Why does klipper don´t find/ cannot open the serial over usb…

mcu 'mcu': Unable to open serial port: [Errno 2] could not open port /dev/serial/by-id/usb-1a86_USB2.0-Serial-if00-port0: [Errno 2] No such file or directory: '/dev/serial/by-id/usb-1a86_USB2.0-Serial-if00-port0'

this is the problem but the path is 100% correct I checked multiple times.

6

The path in your config doesn’t match the path in your screenshot.

Config - /dev/serial/by-id/usb-1a86_USB2.0-Serial-if00-port0

Screenshot - /dev/serial/by-id/usb-1a86_USB-Serial-if00-port0

1 Like