Tip

SB2040 PRO comes pre-flashed with Katapult firmware for CAN connection at a rate of 1M
The Katapult firmware for SB2040 PRO CAN connection supports rates of 500K and 1M; you can flash it as needed
Katapult Firmware Flashing

Firmware Flashing Instructions

Note

To flash the motherboard firmware, you need to flash Klipper via Katapult
If you are sure the motherboard has already been flashed with Katapult, there is no need to perform the Katapult firmware flashing at the end

How to Determine Which Firmware You Need

The SB2040 PRO can connect to the host computer using the following methods
CAN Firmware
- Advantage: If the Katapult firmware is flashed, firmware updates can be performed without touching the motherboard, and bus connection is supported
- Disadvantage: When used with KlipperScreen, it may cause errors such as homing timeout
- Tip: If you need to use CAN, ensure that the host computer supports CAN and needs to be paired with a UTOC or a motherboard flashed with bridge firmware

The SB2040 PRO comes with Katapult firmware for CAN connection at a rate of 1M by default

Name Explanation

Katapult was formerly known as CanBoot, and both names may appear simultaneously in older tutorials or firmware names.

Katapult is a bootloader used to boot and update Klipper:

Katapult itself cannot be used as a Klipper MCU; after flashing, you still need to write Klipper firmware that matches the hardware and communication method.
Supported tool boards can enter Katapult by quickly double-pressing the RESET button; after entering, there is usually a status light blinking.
CAN, RS232, and USB use independent Katapult firmware; you cannot simply modify file names or mix them directly.
For CAN firmware, you must also select the correct bus speed, with common speeds being 500K and 1M.