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?

 

[Rusty105]

So, an update to this....

I finally updated all devices to V0.12.0-418, and it is worse.

Now I get maybe 1 out of 10 prints to fully print. I disabled the V0 Display to take that out of the equation so that only the RasPi, the Picobilical, and the main board , a SKR Pico , are running. I swapped out the remaining USB C cables , to the main board and Picobillical , with different ones. I am at the point that I may try to use UART mode for the RasPi to Mainboard communications. Any ideas on this??

Rusty

 

[Hugedino270]

So, an update to this....

I finally updated all devices to V0.12.0-418, and it is worse.

Now I get maybe 1 out of 10 prints to fully print. I disabled the V0 Display to take that out of the equation so that only the RasPi, the Picobilical, and the main board , a SKR Pico , are running. I swapped out the remaining USB C cables , to the main board and Picobillical , with different ones. I am at the point that I may try to use UART mode for the RasPi to Mainboard communications. Any ideas on this??

Rusty

So I have had this happen when the mcu was feeding power back to the pin via usb. To solve it i placed a small piece of electrical tape over the positive pin on the usb cable on the pi side. Sounds simple but it's worked on 4 of my printers so I just made it standard practice.

 

[gfbarreto]

Possuo duas V0.2 e iniciaram a apresentar o mesmo problema.
O problema acontecia em 99% de qualquer impressão.
Depois de muita busca, testes e desmontagens o que aparentemente acabou resolvendo foi aterra o motor da extrusora.
Talvez seja cedo para falar ainda, mas para quem não conseguia fazer quase nada, hoje as duas impressoras imprimiram o dia inteiro com 100% de sucesso.

 

[Rusty105]

Possuo duas V0.2 e iniciaram a apresentar o mesmo problema.
O problema acontecia em 99% de qualquer impressão.
Depois de muita busca, testes e desmontagens o que aparentemente acabou resolvendo foi aterra o motor da extrusora.
Talvez seja cedo para falar ainda, mas para quem não conseguia fazer quase nada, hoje as duas impressoras imprimiram o dia inteiro com 100% de sucesso.

Google Translation:

I have two V0.2 printers and they started to have the same problem. The problem occurred in 99% of all prints. After much searching, testing and disassembly, what apparently ended up solving the problem was grounding the extruder motor. It may be too early to say yet, but for someone who could barely do anything, today both printers printed all day with 100% success.

Ok, how did you ground the extruder motor? ( Ok, ¿cómo conectaste a tierra el motor del extrusor? )

Rusty

 

[gfbarreto]

Ok, how did you ground the extruder motor? ( Ok, ¿cómo conectaste a tierra el motor del extrusor? )

Rusty

Gambiarra para testar, depois vou fazer definitivo.
Enrolei uma das pontas de um fio numa roela e conectei num gng que estava sobrando no m36.

 

[gfbarreto]

Ok, how did you ground the extruder motor? ( Ok, ¿cómo conectaste a tierra el motor del extrusor? )

Rusty

Gambiarra para testar, depois vou fazer definitivo.
Enrolei uma das pontas de um fio numa roela e aparafusei que pagasse o espaçador e o parafuso e conectei num gnd que estava sobrando no m36.