Raspberry Pi - Klipper install - MCU unable to connect - MCU address shown in file?

Basic Information:

Printer Model: Ender 3 V2 -
MCU / Printerboard:4.2.2
klippy.log
klippy (1).log (510.2 KB)

Just installed Klipper to Raspberry Pi 3B - all seemed to go well, obtained the MCU as
/dev/serial/by-id/usb-1a86_USB_Serial-if00-port0 however still getting the error message mcu ‘mcu’: Unable to connect after rebooting

Any help would be greatful

  • Verify that you have flashed your board with the right make menuconfig settings
  • Repeat the flashing process (change bin filename)
  • Check sudo dmesg directly after attaching the board via USB if it registers correctly

Cheers, I’ve reflashed the board and got the same id /dev/serial/by-id/usb-1a86_USB_Serial-if00-port0 but same issue. I’ve attached the report you mentioned
Sudo dmesg.txt (88.1 KB)
I thought it might have had to be a UART id as I have the ender3 v2 - also checked this and this came back as ttyAMA0

Unless I’m blind there is no trace of a printer board in this dmesg.

  1. Unplug the board
  2. Re-plug it
  3. run dmesg

all done new file attached.

new 2.txt (28.6 KB)

as I’m using the ender 3 v2, I believe the LCD screen won’t work with it, is there away of finding out if the board has been flashed as I have unplugged the screen? Thanks

Strange. The board seems to register fine and I see no traces of other services grabbing the device.

When Klipper successfully connects. Unfortunately these boards use an (stupid) intermediate USB converter chip, so there is no clear indication

would it be wish to rebuild the bin file from the kiauh menu build only and try reflash from that ?

Would change nothing. KIAUH is doing the same as you manually.

oh ok , any other suggestions? on the report was it showing the board this time? do I need another USB cable ? just trying to find a resolution. Followed a tut on youtube using the same gear and everything worked for them, would it make a difference if I switch USB ports on the pi?

You can try:

  • Different cable
  • Different port
  • Reflash again (always use a new filename)

Generally this is not an uncommen combination and many run Klipper successfully

Does dpkg -l |grep modem give any results?

ii libmm-glib0:armhf 1.14.12-0.2 armhf D-Bus service for managing modems - shared libraries
ii modemmanager 1.14.12-0.2 armhf D-Bus service for managing modems

Run
sudo apt remove modemmanager then reboot

just thought while rebuilding the bin file. my pi is powered via the GPIO pins, would I have had to change something there ? also the baud are is set to 250000 is that correct ?

No, this doesn’t change anything if the power supply is adequately dimensioned.

Try removing modemmanager. This is a killjoy

already removed and no change

  • Did you reboot?
  • ls /dev/serial/by-id/* output?
  • dpkg -l | grep -i brltty output?
  • Which Linux distribution / version?

yeah done a complete reboot. Also got this return address : - ls /dev/serial/by-id/
usb-1a86_USB_Serial-if00-port0

when trying dpkg -l | grep -i brltty I get nothing back

Please share a recent klippy.log

klippy (2).log (909.1 KB)

Sorry, out of ideas now.