# Potential issue with new USB to CaN bridge? **URL:** \ **Category:** General Discussion\ **Created:** [July 25, 2022, 7:51am UTC](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577 "2022-07-25T07:51:48Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![AlexOr](https://avatars.discourse-cdn.com/v4/letter/a/977dab/32.png) [@AlexOr](https://klipper.discourse.group/u/AlexOr)\ **Post date:** [July 25, 2022, 7:51am UTC](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/1 "2022-07-25T07:51:48Z")
Hi all, 1st post here, redirected from discord. Set up (on a bench with no steppers connected etc) a new printer configuration involving Octopus Pro, BTT EBB42 v1.0 toolboard connected via Octopus’ onboard RJ11 connector and new Klipper can-usb bridge feature. Everything seems to be working however when I issue firmware\_restart (1st attached log) I’m getting ‘Failed automated reset of MCU ‘tool’’ error. Subsequent restart (2nd log) fixes that. Latest Klipper, bitrate for can is 250,000 [klippy(mcu err).log](https://klipper.discourse.group/uploads/short-url/wjyKEztU8hlghmt5vhGmGxxhSJT.log) (101.2 KB) [klippy(restart).log](https://klipper.discourse.group/uploads/short-url/uD0eYsPEXt9oNhiUdTZRNjxjcFM.log) (210.0 KB) Note that when I had txqueuelen set to 128 in /etc/network/interfaces.d/can0 even restart was not fixing the problem, I had to reboot the whole rig everyt time. with txqueuelen set to 1024 I got restart working, just not firmware\_restart. Given that can-usb bridge is very new is it a known issues or my setup error? Thanks ---
**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:** [July 25, 2022, 8:33am UTC](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/2 "2022-07-25T08:33:03Z")
See [Experimental "USB to CANbus bridge" mode - #37 by koconnor](https://klipper.discourse.group/t/experimental-usb-to-canbus-bridge-mode/3136/37) ---
**Author:** ![jakep\_82](https://avatars.discourse-cdn.com/v4/letter/j/ea666f/32.png) [@jakep\_82](https://klipper.discourse.group/u/jakep_82)\ **Post date:** [July 25, 2022, 5:15pm UTC](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/3 "2022-07-25T17:15:09Z")
As I noted in that thread, you can work around this by not making your bridge MCU the main MCU, and listing it last in your config. ---
**Author:** ![AlexOr](https://avatars.discourse-cdn.com/v4/letter/a/977dab/32.png) [@AlexOr](https://klipper.discourse.group/u/AlexOr)\ **Post date:** [July 25, 2022, 10:39pm UTC](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/4 "2022-07-25T22:39:22Z")
Thanks a lot. That must be it - since it is a know issue and there is a chance it’ll be fixed in the future, I don;t mind hitting restart instead of firmware restart for some time. Thank you all. ---
**Author:** ![koconnor](https://avatars.discourse-cdn.com/v4/letter/k/aca169/32.png) [@koconnor](https://klipper.discourse.group/u/koconnor)\ **Post date:** [July 29, 2022, 5:50pm UTC](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/5 "2022-07-29T17:50:56Z")
FYI, the latest Klipper code now has improved reset ordering of FIRMWARE\_RESTART commands for “bridge” mcus (commit 751bff7d). It does require upgrading and reflashing the mcu. -Kevin ---
**Author:** ![AlexOr](https://avatars.discourse-cdn.com/v4/letter/a/977dab/32.png) [@AlexOr](https://klipper.discourse.group/u/AlexOr)\ **Post date:** [July 30, 2022, 1:56am UTC](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/6 "2022-07-30T01:56:39Z")
Thanks a lot @koconnor ! Update: Upgraded klipper via update manager (it did not raise an error that mcu needed to be reflashed as I expected). Reflashed all mcu’s anyway and the issues is gone. Thanks! ---
**Author:** ![richard\_kis](https://avatars.discourse-cdn.com/v4/letter/r/eb9ed0/32.png) [@richard\_kis](https://klipper.discourse.group/u/richard_kis)\ **Post date:** [April 5, 2024, 9:20am UTC](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/7 "2024-04-05T09:20:49Z")
Hello, for a some reason I still have a problem with FIRMWARE\_RESTART in CAN bridge mode. Firmware version: v0.12.0-8, BTT Octopus plus Fly Mellow SB2040 CAN toolhead. MCU configuration as below. Please, could you check? BTW I use canboot mode in 2040 toolhead, could this have some influence? [mcu] canbus\_uuid: 0692bed3a983 [mcu SB2040] canbus\_uuid: 40120b79508a ---
**Author:** ![TheFuzzyGiggler](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/thefuzzygiggler/32/12313_2.png) [@TheFuzzyGiggler](https://klipper.discourse.group/u/TheFuzzyGiggler)\ **Post date:** [April 5, 2024, 10:03am UTC](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/8 "2024-04-05T10:03:10Z")
Please start a new thread, this one is 2 years old. Avoid necroing old threads in the future, you can just reference them as… I have such and such issue as described here: [https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/7](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/7) ---
**Author:** ![EddyMI3D](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/eddymi3d/32/1981_2.png) [@EddyMI3D](https://klipper.discourse.group/u/EddyMI3D)\ **Post date:** [April 5, 2024, 2:31pm UTC](https://klipper.discourse.group/t/potential-issue-with-new-usb-to-can-bridge/3577/9 "2024-04-05T14:31:57Z")