Question Newly build V0.2r1 having mcu disconnect issues.

[Rusty105]

Starting to wrap up the build of my V0.2r1, LDO kit, and I am running into a frustraiting issue with klipper losing connection with mcu 'mcu'. It doesn't happen on smaller prints, maybe 30 minutes or less, but anything more than that it is like playing roulette. Half way through a 3 hour print and klipper shuts down after losing connection to mcu 'mcu' , which I am assumeing in the BTT-Pico. Only powering down will fix the issue.

All the electronics are as they came in the LDO kit, The RasPi 4 is connected to the Pico by USB. It also has the Picobilical and I added a V0 display, all in all 3 seperate mcus, but it always loses connection to mcu 'mcu'. For clarity the other two mcus are 'mcu-umb' and 'mcu-display' the one tagged 'mcu' is the BTT-Pico.

Any thoughts on why this is happening?

 

[Sandman50]

The pi and the main board are loosing the connection. So start with the basics. Check the wires - wiggle them a bit when it's powered up to see what happens. It could also be power to the Pico, but not as likely. Check those wires just the same.

What Pi are you using and what OS image?

I've had the SD cards start to go bad on Pis - though not for klipper machines. Just killing the power to the pi can corrupt the SD card - really need to do an elegant shutdown via command line. (which can be added to the micro display as a command). This one is speculative on my part.

 

[claudermilk]

I second that suggestion, double check all connections. I had some issues with the umbilical connecting solidly as well as the darn 5V for the Pi. That's the only little complaint I have about the entire kit.

I've also had an SD card go bad seemingly from power outages.

 

[Rusty105]

USB cables are tight, and new (came with the kit) I can try some known good cables and see if it makes a difference.

It is a Pi4, 2GB I believe, it came with the kit as well.... Don't remember the OS image, but it is the lite version. I'll update later at home.

The Pico is powered directly from the power supply, The Pi is powered from the Picobilical board via the 5V output to the ADXL hat on the PI

 

[Rusty105]

OK, so a firmware check across all devices....

Raspi v0.12.0-396-gb7233d119
Pico mcu v0.12.0-384-g847331260
Picobilical mcu v0.12.0-31-g6676c1df
Display mcu v0.12.0-384-g847331260

As for OS on the RasPi : Raspbian GNU/Linux 12 (bookworm)

How close do the firmware versions need to be? is V0.12.0 enough?

Rusty

 

[Sandman50]

Current Klipper is: 0.12.0-396 - so you are close enough. But you might want to upgrade the rest to 396 and see if that's the problem.

Also update / upgrade the Pi so that is all current.

sudo apt update && sudo apt upgrade -y

The shutdown code for the V0 default display:

#Shutdown from: https://klipper.discourse.group/t/shutdown-command-to-the-raspberry/584/3
[delayed_gcode shutdown_machine]
gcode:
     {action_call_remote_method("shutdown_machine")}
initial_duration: 0.0
[menu __main __poweroff]
type: command
enable: {printer.idle_timeout.state != "Printing"}
name: Safely Shutdown
gcode:
     M117 Shutdown_RPI
     M118 Shutdown_RPI
     { menu.exit() }
     UPDATE_DELAYED_GCODE ID=shutdown_machine DURATION=1

If all the wires are have been wiggled and they are good, then perhaps start the installation process over? Once the pi is up and running, I use Kaiuh to install everything else.

GitHub - dw-0/kiauh: Klipper Installation And Update Helper

Klipper Installation And Update Helper. Contribute to dw-0/kiauh development by creating an account on GitHub.

github.com

Long shot, but are your USB cables dressed near 120VAC line power?