The source code for the bootloaders can be found in AP_Bootloader but pre-compiled binaries are available for many boards in the Tools/Bootloaders directory on our firmware server. Please refer to the README.txt to see if one of the existing bootloaders is compatible for the new board.

Flash the bootloader

We have currently two ways to flash the ArduPilot bootloader : - flashing the one embedded into the firmware with MAVLink (recommended) - using DFU mode to flash

With DFU

Some boards come with a bootloader pre-installed while others rely on the board manufacturer to use dfu to install the firmware to the board. In either case, in order to conveniently load ArduPilot to the board over USB, an ArduPilot compatible bootloader must be uploaded to the board using dfu. “dfu” can be downloaded from here.


Your board must be plugged into USB and in DFU mode. DFU mode is usually entered by shorting two pins together on the board. Please see your board’s documentation for details on how to accomplish this.

Upload the bootloader to the board dfu-util -a 0 --dfuse-address 0x08000000 -D new-board-bootloader.bin -R