# Trouble with katapult **URL:** \ **Category:** General Discussion\ **Created:** [June 8, 2025, 12:54am UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819 "2025-06-08T00:54:48Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![ten57](https://avatars.discourse-cdn.com/v4/letter/t/258eb7/32.png) [@ten57](https://klipper.discourse.group/u/ten57)\ **Post date:** [June 8, 2025, 12:54am UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/1 "2025-06-08T00:54:48Z")
### Basic Information: Printer Model: mercury zerog MCU / Printerboard:kraken Host / SBC btt pi klippy.log _Fill out above information and_ **_in all cases attach your_ `klippy.log` _file_** (use zip to compress it, if too big). _Pasting your_ `printer.cfg` _is **not** needed_ _ **Be sure to check our “Knowledge Base” Category first. Most relevant items, e.g. error messages, are covered there** _ ### Describe your issue: So I’m installing a ebb36 following the esoteric canbus guide and can’t get back to klipper from katapult … ---
**Author:** ![KosstAmojan](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@KosstAmojan](https://klipper.discourse.group/u/KosstAmojan)\ **Post date:** [June 8, 2025, 9:39am UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/2 "2025-06-08T09:39:18Z")
Hi ten57, katapult is only the bootloader (needed for CAN implementation). After you flashed successfully katapult, you have to flash (over CAN) klipper. Here are general instructions for flashing katapult and klipper via CAN: > **[Bootloader Katapult \[Dr. Klipper Wiki\]](https://drklipper.de/doku.php?id=klipper_faq:can:66_-_katapult-bootloader)** And here is the instruction for flashing klipper via CAN specialy for EBB36: > **[BTT EBB36 / EBB42 (CAN) \[Dr. Klipper Wiki\]](https://drklipper.de/doku.php?id=klipper_faq:flash_guide:stm32g0b1:btt_ebb36_ebb42_can&s%5B%5D=%2Aebb36%2A)** I know, the articles are in german, but I hope it helps you. It is extremely important that you set the correct bootloader offset for the EBB36 when compiling klipper. ---
**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\ **Post date:** [June 8, 2025, 10:08am UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/3 "2025-06-08T10:08:16Z")
> [@ten57](#): > > esoteric canbus guide Stick to these guides. They are excellent. As mentioned by @KosstAmojan, you probably forgot or not correctly flashed Klipper. Installing Katapult will delete the entire flash memory and as long as no Klipper firmware is installed the board will only come up in Katapult / Bootloader mode. ---
**Author:** ![KosstAmojan](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@KosstAmojan](https://klipper.discourse.group/u/KosstAmojan)\ **Post date:** [June 8, 2025, 10:41am UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/4 "2025-06-08T10:41:39Z")
And, very important, have you set the 120Ohm resistor for the CAN bus? If not, you get no or not a stable connection to the toolhead for flashing. ---
**Author:** ![ten57](https://avatars.discourse-cdn.com/v4/letter/t/258eb7/32.png) [@ten57](https://klipper.discourse.group/u/ten57)\ **Post date:** [June 9, 2025, 12:51am UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/5 "2025-06-09T00:51:37Z")
I believe i got klipper back but now it won’t connect to mcu ---
**Author:** ![3dcoded](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/3dcoded/32/20297_2.png) [@3dcoded](https://klipper.discourse.group/u/3dcoded)\ **Post date:** [June 9, 2025, 11:30am UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/6 "2025-06-09T11:30:44Z")
Could you upload a `klippy.log`? ---
**Author:** ![KosstAmojan](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@KosstAmojan](https://klipper.discourse.group/u/KosstAmojan)\ **Post date:** [June 9, 2025, 11:34am UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/7 "2025-06-09T11:34:47Z")
Did you set the right can\_uuid in printer.cfg? for both, board and toolhead ? Something linke ```auto [mcu EBBCan] ## uncomment mcu communication type you use ## for serial: obtain definition by "ls /dev/serial/by-id/*" then unplug to verify ## for CAN: obtain can uuid by ""~/klippy-env/bin/python ~/klipper/scripts/canbus_query.py "" # serial: /dev/serial/by-id/usb-Klipper_Klipper_firmware_12345-if00 canbus_interface: can0 # default is "can0" canbus_uuid: 2e12ab8ec8ce ``` And ```auto [mcu] ## uncomment mcu communication type you use ## for serial: obtain definition by "ls /dev/serial/by-id/*" then unplug to verify ## for CAN: obtain can uuid by ""~/klippy-env/bin/python ~/klipper/scripts/canbus_query.py "" # serial: /dev/serial/by-id/usb-Klipper_Klipper_firmware_12345-if00 canbus_interface: can0 # default is "can0" canbus_uuid: 34943f8a8f6b ``` ---
**Author:** ![ten57](https://avatars.discourse-cdn.com/v4/letter/t/258eb7/32.png) [@ten57](https://klipper.discourse.group/u/ten57)\ **Post date:** [June 9, 2025, 1:55pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/8 "2025-06-09T13:55:44Z")
Do I replace my original mcu, with that ---
**Author:** ![ten57](https://avatars.discourse-cdn.com/v4/letter/t/258eb7/32.png) [@ten57](https://klipper.discourse.group/u/ten57)\ **Post date:** [June 9, 2025, 2:21pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/9 "2025-06-09T14:21:31Z")
[klippy (5).log](https://klipper.discourse.group/uploads/short-url/rQ6BVn4LaWnuOWxqWrPP9o3Gd6h.log) (606.3 KB) i was at work so couldn’t post klippy ---
**Author:** ![KosstAmojan](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@KosstAmojan](https://klipper.discourse.group/u/KosstAmojan)\ **Post date:** [June 9, 2025, 3:32pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/10 "2025-06-09T15:32:37Z")
Standard way is to use serial connection for board mcu and eddy mcu (snippet from your klippy.log): ```auto [mcu] serial = /dev/serial/by-id/usb-Klipper_stm32h723xx_0C0013000C51323532393433-if00 [mcu eddy] serial = /dev/serial/by-id/usb-Klipper_rp2040_50445061304E4E1C-if00 ``` You flashed katapult (can bootloader) and klipper on your board and eddy, so you have to set your mcu connections with CAN bus in your printer.cfg. If you use the esoterical can guide look here: > **[Final Steps](https://canbus.esoterical.online/Final_Steps.html)** > > A guide for setting up CANBus hardware on 3D printers ---
**Author:** ![KosstAmojan](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@KosstAmojan](https://klipper.discourse.group/u/KosstAmojan)\ **Post date:** [June 9, 2025, 3:38pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/11 "2025-06-09T15:38:15Z")
And as I see, your klippy.log says, you have the eddy connected via I²C and not via CAN: ```auto [probe_eddy_current btt_eddy] sensor_type = ldc1612 z_offset = 2 i2c_mcu = eddy i2c_bus = i2c0f ``` ---
**Author:** ![ten57](https://avatars.discourse-cdn.com/v4/letter/t/258eb7/32.png) [@ten57](https://klipper.discourse.group/u/ten57)\ **Post date:** [June 9, 2025, 4:23pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/12 "2025-06-09T16:23:56Z")
what do i change the eddy to and ive made the changes you suggested and still unable to connect ---
**Author:** ![KosstAmojan](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@KosstAmojan](https://klipper.discourse.group/u/KosstAmojan)\ **Post date:** [June 9, 2025, 5:46pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/13 "2025-06-09T17:46:10Z")
First: what kind of “eddy” do you have? There are 3 eddy’s: 1. Eddy Coil (only I²C; no USB or CAN connection) 2. Eddy USB (only USB, for direct connection to a Pi, no CAN, no I²C connection) 3. Eddy Duo (USB or CAN; no I²C connection) Do you compile klipper for the Eddy with the right settings? USB: > CAN: ![384601845-e60728d1-98c9-42ef-89f1-c04a19966559](https://global.discourse-cdn.com/free1/uploads/klipper/original/3X/8/c/8c2936968a19b40950a1c2260266badc61e4014f.png) The sample printer.cfg on the BTT EDDY github is only for the I²C or USB connection. Here is a thread on github which seams to solve the can setup problem: > > > Hello, > > I connected it to BTT EBB SB2209, and now I can see the uuid. > > Found… canbus\_uuid=91464af9d0e2, Application: CanBoot > > now I want to compile the klipper firmware to flash to the eddy. > > !\[image\](https://github.com/user-attachments/assets/e60728d1-98c9-42ef-89f1-c04a19966559) > > Which pins do I need to enter in \`make menuconfig\`? ---
**Author:** ![ten57](https://avatars.discourse-cdn.com/v4/letter/t/258eb7/32.png) [@ten57](https://klipper.discourse.group/u/ten57)\ **Post date:** [June 9, 2025, 10:32pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/14 "2025-06-09T22:32:36Z")
duo im lost i tried flashing it its not coming up when i **ls /dev/serial/by-id/** \* ---
**Author:** ![KosstAmojan](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@KosstAmojan](https://klipper.discourse.group/u/KosstAmojan)\ **Post date:** [June 10, 2025, 3:45pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/15 "2025-06-10T15:45:40Z")
And that’s good =\> if you have a Duo with the switch to CAN (instead of USB) and flashed katapult (CAN bootloader) and klipper via CAN, because you don’t have a serial device anymore. Or do you want the Eddy Duo connect via USB with the SBC (f.e. BTT Pi)? You should only have the “can bridge device” as serial device (plus the on-board-devices from the Pi). > **[BigTreeTech Kraken](https://canbus.esoterical.online/mainboard_flashing/common_hardware/BigTreeTech%20Kraken/README.html)** > > A guide for setting up CANBus hardware on 3D printers > **[BigTreeTech EBB36 V1.2](https://canbus.esoterical.online/toolhead_flashing/common_hardware/BigTreeTech%20EBB36%20V1.2/README.html)** > > A guide for setting up CANBus hardware on 3D printers ---
**Author:** ![ten57](https://avatars.discourse-cdn.com/v4/letter/t/258eb7/32.png) [@ten57](https://klipper.discourse.group/u/ten57)\ **Post date:** [June 10, 2025, 5:40pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/16 "2025-06-10T17:40:17Z")
im not getting anywhere i cant flash klipper back to main board ![Screenshot 2025-06-10 055148](https://global.discourse-cdn.com/free1/uploads/klipper/original/3X/a/a/aa77eff2e34bd7bae7ebce6b692e4771e95bcaa5.png) ---
**Author:** ![KosstAmojan](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@KosstAmojan](https://klipper.discourse.group/u/KosstAmojan)\ **Post date:** [June 10, 2025, 5:56pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/17 "2025-06-10T17:56:50Z")
Yes, you CAN (and without Obama 😉 ) as your picture shows: OpenMoko, Inc. Geschwister Schneider CAN adapter. that’s the CAN bridge adapter (example : [Dedicated USB CAN Device | Esoterical’s CANBus Guide](https://canbus.esoterical.online/Dedicated_USB_Can_Device.html) ) follow the esoterical CAN guide: > **[BigTreeTech Kraken](https://canbus.esoterical.online/mainboard_flashing/common_hardware/BigTreeTech%20Kraken/README.html)** > > A guide for setting up CANBus hardware on 3D printers ---
**Author:** ![ten57](https://avatars.discourse-cdn.com/v4/letter/t/258eb7/32.png) [@ten57](https://klipper.discourse.group/u/ten57)\ **Post date:** [June 10, 2025, 6:05pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/18 "2025-06-10T18:05:10Z")
is it supposed to stay saying OpenMoko, Inc. Geschwister Schneider CAN adapter. ---
**Author:** ![KosstAmojan](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@KosstAmojan](https://klipper.discourse.group/u/KosstAmojan)\ **Post date:** [June 10, 2025, 6:06pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/19 "2025-06-10T18:06:39Z")
That’s the CAN Interface. > **[Mainboard Flashing](https://canbus.esoterical.online/mainboard_flashing)** > > A guide for setting up CANBus hardware on 3D printers ---
**Author:** ![KosstAmojan](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@KosstAmojan](https://klipper.discourse.group/u/KosstAmojan)\ **Post date:** [June 10, 2025, 6:11pm UTC](https://klipper.discourse.group/t/trouble-with-katapult/23819/20 "2025-06-10T18:11:30Z")
Maybe this would help: it’s a step-by-step guide for the Octopus Pro board [![](https://global.discourse-cdn.com/free1/uploads/klipper/original/3X/5/c/5c23ec4f9273f43e8d18fe68e1a47e94c27ce9a0.jpeg "#116 - Klipper von 0 auf 100 - Pi4, Octopus Pro (Bridge), EBB36") ](https://www.youtube.com/watch?v=EJNHkLn1_qM) and here one for the BTT Manta M8Pv2: [![](https://global.discourse-cdn.com/free1/uploads/klipper/original/3X/6/7/675cb463482b1f09dbac9e9522524b957fa5e6bc.jpeg "#121 - Klipper von 0 auf 100 - BTT CB1, Manta M8P, SB2209") ](https://www.youtube.com/watch?v=3XnImjWQ12U) The configuration of the klipper firmware is different, but the steps should be the same for the Kraken board. [Next page](https://klipper.discourse.group/t/trouble-with-katapult/23819.md?page=2)