'mcu': Unable to connect on Duet3D 2 WiFi via fluidd

General Discussion
1

I recently began a rebuild of my Airwolf3D AXIOM in which I replaced my RAMBo with a Duet3D 2 WiFi and Raspberry Pi running Klipper via fluidd as well as added a BLTouch. I have followed the guides at klipper3d and docs.fluid.xyz and everything seemed to be going well (fluidd alerted me to a couple issues in my printer.cfg which I was able to remedy) until I started getting the following message during the Klipper startup in fluidd:

mcu ‘mcu’: Unable to connect
Once the underlying issue is corrected, use the
“FIRMWARE_RESTART” command to reset the firmware, reload the
config, and restart the host software.
Error configuring printer

After searching the forums and finding some similar issues, I decided to try reflashing Klipper to my Duet. Unfortunately, this caused absolutely no noticeable improvement in the situation and the issue persists. My klippy.log ends with the following:

Traceback (most recent call last):
File “/home/pi/klipper/klippy/serialhdl.py”, line 69, in _get_identify_data
params = self.send_with_response(msg, ‘identify_response’)
File “/home/pi/klipper/klippy/serialhdl.py”, line 258, in send_with_response
return src.get_response([cmd], self.default_cmd_queue)
File “/home/pi/klipper/klippy/serialhdl.py”, line 316, in get_response
cmd_queue)
File “/home/pi/klipper/klippy/serialhdl.py”, line 250, in raw_send_wait_ack
self._error(“Serial connection closed”)
File “/home/pi/klipper/klippy/serialhdl.py”, line 62, in _error
raise error(self.warn_prefix + (msg % params))
error: mcu ‘mcu’: Serial connection closed

Any assistance that can be provided on this matter would be immensely appreciated. I have also attached my klippy.log and printer.cfg files in hopes that someone may be able to catch something I have overlooked, etc. Thank you, in advance, for any and all assistance.

klippy (2).log (136.2 KB)
printer.cfg (2.2 KB)

2

From your cfg:

[mcu]
serial: /dev/serial/by-id/usb-Duet3D_Duet-if00

This looks like that either the board is not correctly flashed or the wrong serial path in the cfg. It usually contains “klipper” in the path.

Please closely follow klipper | Klipper is a 3d-printer firmware . If that is not working, paste the output from the ls /dev/serial/by-id/* and make flash command here.

3

I believe the Duet boards require a special flashing process which is detailed here.

1 Like
4

I might be mistaken, but doesn’t Klipper already take care of it?

5

The flash process is fully automatic on Duet 2 WiFi, except:

The very first flash only (when moving from RRF to Klipper) requires the Duet 2 erase jumper to be briefly jumpered before issuing the ‘make flash’ command. The erase jumper should be removed as soon as the Diag LED lights up. This indicates that the board has been successfully placed in programming mode.

Once Klipper has been installed on the board this jumpering is no longer required…

1 Like
6

I think you want to run the following command over ssh on your raspberry pi

ls /dev/serial/by-id/*

take the output of that command and post it as your mcu setting like the below setting from my config file

[mcu]
#serial: /dev/ttyAMC0
serial: /dev/serial/by-id/usb-Klipper_sam4e8e_00313953325753543039303330303630-if00