Open Bootloader with DFU

The Open Bootloader example uses the Bootloader and DFU modules to implement a bootloader with Device Firmware Update (DFU) functionality. Open bootloader has relaxed security compared to the Secure Bootloader.

• Application update may come from an unsigned package (NRF_DFU_REQUIRE_SIGNED_APP_UPDATES).
• SoftDevice update may come from an unsigned package if the bootloader does not depend on the SoftDevice (NRF_DFU_REQUIRE_SIGNED_APP_UPDATES).
• Bootloader update must come from signed packages.
• Single-bank updates are preferred (NRF_DFU_SINGLE_BANK_APP_UPDATES).
• Firmware version get command is supported (NRF_PROTOCOL_FW_VERSION_MSG).

The open bootloader example (examples/dfu/open_bootloader) is provided only with USB CDC ACM DFU Transport.