Secure DFU OTA for nRF52840 solution modules: Guide to create hex/zip file for implementation – #1(Bootloader)

Below are the following steps to implement Secure DFU OTA by using nRF52840 chip set, SDK17.1.0.
It consists of 3 parts:

Part A: Bootloader

Part B: Application (Click for article link)

Part C: Combining and merging built files (Click for article link)

In this article, we will be focusing on Part A: Bootloader.

Path: nRF5_SDK_17.1.0_ddde560\examples\dfu\secure_bootloader\pca10056_s140_ble\arm5_no_packs


Step 1. An error may occur while building bootloader without a public key:
(Shown in red frames in below screenshot)


Step 2. How to generate the public key file in Bootloader?
A. Visit DOS at path: ..\Python27\Scripts
B. Then execute:

nrfutil keys generate private.pem
nrfutil keys display --key pk --format code private.pem --out_file public_key.c


Step 3. Copy the pk[64] code from (public_key.c) into (dfu_public_key.c)
(Shown in red frames in below screenshot)

※Note: Make sure to save the 3 generated files:
private.pem
public_key.c
dfu_public_key.c


Step 4. Generate the bootloader file: nrf52840_xxaa_s140.hex after re-compiling the code files.


※Stay tuned for #2 – Part B: Application in the next article, scheduled release in next week(29/05/2024).



Technical guidelines provided by R&D Manager: Mr. MW Lee
Edited by Sales Manager: Mr. Tony Yin


Raytac Corporation 勁達國際電子股份有限公司  A company of Abietec
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