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CanBoot bootloader (optional)

Canboot is a bootloader for MCUs to be able to update/flash them via CANBUS. With CanBoot there is no physical intervention (e.g. pressing the boot button) required to flash/update firmware to the MCUs.

This guide is tested with the following boards:

  • BigTreeTech U2C v2.1

This guide was verified on a Pi running MainsailOS

Download CanBoot

Clone the CanBoot repository: 

cd ~
git clone https://github.com/Arksine/CanBoot
To add CanBoot to your moonraker update manager, add this section to your config (optional):
moonraker.conf
[update_manager canboot]
type: git_repo
origin: https://github.com/Arksine/CanBoot.git
path: ~/CanBoot
is_system_service: False

Configure CanBoot

Open the config dialog with the following commands: 

cd ~/CanBoot
make menuconfig
and use following config settings:

  • Micro-controller Architecture: STMicroelectronics STM32
  • Processor model: STM32G0B1
  • Build CanBoot deployment application: 8KiB bootloader
  • Clock Reference: 8 MHz crystal
  • Communication interface: USB (on PA11/PA12)
  • Application start offset: 8KiB offset
  • Support bootloader entry on rapid double click of reset button: check
  • Enable Status LED: check
  • Status LED GPIO Pin: PA13

this should then look like this:

CanBoot config

CanBoot config for U2C v2.x

use q for exit and y for save these settings.

These lines just clear the cache and compile the CanBoot bootloader: 

make clean
make

Flash CanBoot

First, you have to put the board into DFU mode. To do this, press and hold the boot button and then disconnect and reconnect the power supply. With the command dfu-util -l, you can check if the board is in DFU mode.

If dfu-util can discover a board in DFU mode it should then look like this: dfu-util -l If this is not the case, repeat the boot/restart process and test it again.

If your board is in DFU mode, you can flash CanBoot with the following command: 

dfu-util -a 0 -D ~/CanBoot/out/canboot.bin -s 0x08000000:mass-erase:force:leave
dfu-util -l Now power cycle the board if the flash process was successfully one LED should blink now.