This is a very brief overview on how to install Arksine’s katapult (formerly CanBoot) onto the SKR Mini E3 v2 without any additional special hardware. The primary motivation is to allow updating the Mini via USB using the standard Klipper
make flash command with no need for SD card based flashing. The same fundamental approach can be used on other BTT SKR boards, but exact configuration settings will need to be adjusted accordingly.
This procedure is similar to the one outlined by @Sineos in CanBoot: Flash BTT SKR 1.3 / 1.4 / 1.4 Turbo, but instead of requiring any additional hardware it relies purely on the katapult “deployer mode”.
CAUTION: This will remove the BTT bootloader and replace it with katapult. You will no longer be able to update the firmware using the SD card! I strongly recommend that you back-up the original bootloader first by using the following command:
~/klippy-env/bin/python ~/klipper/scripts/dump_mcu.py -l 0x7000 /dev/ttyACM0 ~/bootloader_backup.bin. If anything goes wrong during this process your SKR board will become unusable until a functional bootloader is installed. This will require additional external programming hardware.
Install katapult following the instructions on GitHub: katapult.
Use the following configuration during
Compile katapult and then transfer the
~/katapult/outdirectory to a suitable SD card.
deployer.binon the SD card to
Insert the SD card into BTT SKR Mini E3 v2 and power up the SKR. Note the Status LED will briefly flash as the bootloader is being flashed.
The SKR status LED will start flashing slowly as the board resets and enters the katapult bootloader mode. If the bootloader mode is needed at a later time, rapidly double-clicking the RESET button on the board with place it in bootloader mode.
When configuring klipper for the modified board with
make menuconfigdo not use
28KiB bootloadersetting but instead use
8KiB bootloadersetting for katapult bootloader.
Flash Klipper onto the modified SKR board using the standard flash command
make flash FLASH_DEVICE=/dev/ttyACM1. Make sure to use the correct device name.
That’s all folks! Many thanks to Arksine for his ongoing development of the Klipper ecosystem!