Question Lost communication with MCU 'EBBCan'

[maestro]

I'm experiencing a random connection issue and am seeking assistance with resolving it. I have a Voron 2.4 Formbot kit with BTT Manta M8P 2.0 + CB1 connected to EBB SB2209 CAN V1.0 (RP2040) via CAN. Randomly, during the printing, I'm getting an error "Lost communication with MCU 'EBBCan' Once the underlying issue is corrected, use the "FIRMWARE_ RESTART" command to reset the firmware, reload the config, and restart the host software. Printer is shutdown". This could happen after 3 minutes of printing, or after 30-40 minutes, or not occur during more than 1 hour of printing. After a firmware restart, everything is back to normal, and a new print can be started again right away.

What I've tried/did so far:

1. Upgraded Klipper to the latest version and reflashed the latest version of firmware everywhere.
2. As was described in the GitHub issue https://github.com/bigtreetech/EBB/issues/164, I added grounding for the extruder motor.
3. Unfolded the CAN cable and removed it from the case.
4. Tried checking connections, detached/reattached cables.
5. Disassembled and assembled the toolhead to make sure the extrusion is smooth and the filament does not get stuck.
6. Verified voltage on the PCU during the print - stable 24.2V, no drops.
7. Bought another EBB SB2209 CAN V1.0 (RP2040) + cable and replaced everything (board and cable one by one).
8. Track the temperature of EBB. It's in operational limits and does not get higher than 60-65 degrees.

Nothing from above helped. Random disconnects continue. Another thing I noticed is that it looks like the toolhead continues moving even after the filament has already stopped extruding. The following picture demonstrates this. Another thing I noticed is that all interruptions occur during the solid infill printing.



I'm attaching logs and my assembly photo (I use a cable fastening clip "EBB SB2240_2209 CAN/CAD/Printed_Part_for_CAN_Cable_V1.2.STEP" to immobilize the connection, but it is detached in this photo).



I'm also attaching my logs. I would appreciate any help with this.

 

[Maas101]

I'm not sure how good the CAN implementation is in the M8P. You could try adding a BTT U2C usb->can interface and connecting that via usb to your M8P. I have one and have never had a can issue I couldn't directly attribute to a dodgy cable connection.

 

[maestro]

I'm not sure how good the CAN implementation is in the M8P. You could try adding a BTT U2C usb->can interface and connecting that via usb to your M8P. I have one and have never had a can issue I couldn't directly attribute to a dodgy cable connection.

Thank you for the suggestion. I have not thought about it. That is a good idea, and I probably need to get a BTT U2C USB-to-CAN interface to try it. I will post an update here once I get one. In the meantime, I have also created a GitHub issue for BTT, but I have not received any replies there yet: https://github.com/bigtreetech/EBB/issues/169.

 

[maestro]

Finally, it looks like I resolved the issue. The root cause, most likely, was not in the hardware. I'm using Armbian as an OS on my host, and I had an issue with its configuration. During the initial setup, I had a problem with the networking settings, and it did not work properly. I reinstalled everything from scratch using the latest available versions, including Armbian, and carefully configured all networks, and the problem is gone. I put together a couple of step-by-step configuration tutorials for myself, but maybe they will be useful for someone else:
- https://github.com/oleksii-suprun/klipper-voron24-300/blob/main/doc/cb1_networkmanager_guide.md
- https://github.com/oleksii-suprun/klipper-voron24-300/blob/main/doc/can0_setup_guide.md
- https://github.com/oleksii-suprun/klipper-voron24-300/blob/main/doc/manta_m8p_can_setup_guide.md

 

[Regressor]

Hi. I had the same problem. I thought I solved it by putting a capacitor on the EBB board's power contacts. The problem went away for a while (I was printing projects lasting over 20 hours), but a couple of days ago it returned.

In the process of fixing it, I replaced almost everything—the power supply, the EBB board, the cable. I updated the firmware numerous times. I filmed the error and discovered that before the klipper displays an error, the EBB microcontroller simply reboots (I programmed the MSU bootloader to turn on the red LED during boot, and turn it off when the klipper is activated).

Apparently, this is some kind of defective EBB board.

But.... What heater do you have on you hotend ? My is Torlipy 70W 6*20 мм для E3D V6 Volcano...

P.S. I changed hotend to Revo (40W heater and result the same).

 

[maestro]

Hello. The issue returned for me as well. I worked for some time (perhaps by luck), but the problem reappeared after a month or so. The print stops with the same error after 5-7 minutes. I put all the details here https://github.com/bigtreetech/EBB/issues/169.

I have a Formbot kit with Manta M8P + BTT EBB 2209. I have an E3D Revo hotend with a 60W header and HF nozzle. As an attempt to fix, I already did the following things, but nothing helped:

1. Tried another BTT EBB 2209 board and cable.
2. Attempted to reduce the extruder motor current.
3. Reduce max extrusion rate from 20 mm3/s to 8 mm3/s
4. Reduce print speed.
5. Replace the Manta M8P built-in CAN bridge with an external USB-to-CAN adapter (BTT U2C https://github.com/bigtreetech/U2C).
6. Reflash everything and reduce the CAN bitrate from 1000000 to 500000.
7. Swiched from CB1 to CM4

Nothing from above helped. However, after several experiments today, I discovered that all prints finish successfully when I run them as a "dry run" (printing without filament). Even reprinting the same G-Code without filament completes successfully and fails with filament. It seems that for me, the problem could be narrowed to heating or extrusion.

@Regressor, I hope the summary above gives you information about my setup. Could you please also share information on what the power of your new PSU is? Is it the same 200W or greater?

 

[5twenty]

You have them communicating the same baud?

 

[maestro]

Yes, everything was configured to 1000000, then everything was reconfigured (including can0 network) to 500000.

I had a chat with some folks on Voron Discord and several people agreed the issue is most likely because of a bad cable connection due to a missing strain relief. Yesterday I disassembled tool head and extracted the EBB board but did not see any visible damage. I will try to take a closer look today and probably try to re-solder the connection. The main issue is that even this is a bad connection because of a strain, to print a strain relief I have to have an operational printer. It looks like a "chicken and egg" problem.

 

[5twenty]

Yes, those moving toolheads can cause some errant issues. I had a thermistor that had a loose connection, but every time I took it apart to find the issue, it presented as nothing and was strong. Somehow it was moving JUST enough while printing, and I couldn't reproduce it manually...last E3D product I'll ever use.

 

[vukrook]

I ran into the very same error message, occurring with EBB36.
Finally it was an occasional bad male-to-female connection inside the connector.
Re-crimped the pins, then I made a 70mm TPU extension sleeve for the CAN cable a) to precisely attach to the outlet, and b) to mate the cable with EBB38 without bending.
I was already worried if PCB connector-pins re-soldering would be the next step.