Tip

The SB2040 comes pre-flashed with Katapult firmware for CAN connection at a rate of 1M
Katapult firmware for SB2040 CAN connection is available in both 500K and 1M rates, and can be re-flashed if needed
Katapult firmware flashing

Firmware Flashing Instructions

Notes

Mainboard firmware flashing requires flashing Klipper via Katapult
If you are certain the mainboard already has Katapult flashed, there is no need to flash the Katapult firmware at the end

Choose Firmware Type

Please confirm the connection method first

Firmware Type	Applicable Scenario	Advantages	Confirm Before Selecting	Operation
CAN Firmware	When a CAN toolboard is needed	Supports connecting multiple devices via CAN bus	Confirm the host supports CAN, and prepare a UTOC or USB-CAN bridge board	Compile CAN Firmware

Name Description

Katapult was formerly named CanBoot; both may appear simultaneously in old tutorials or old firmware names.

Katapult is the bootloader used to boot and update Klipper:

Katapult itself cannot be used as a Klipper MCU; after flashing, the Klipper firmware matching the hardware and communication method still needs to be written.
The method for entering Katapult is subject to the current product page: boards with a RESET button can enter by quickly double-pressing RESET; boards with only a BOOT button require fully powering off first, then holding BOOT while connecting USB, and releasing it once the device is recognized. After entering, there is usually a status LED blinking.
CAN, RS232, and USB use mutually independent Katapult firmware and cannot be mixed by simply changing the file name or using them directly.
CAN firmware must also select the correct bus rate; common rates are 500K and 1M.