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

Here are the guidelines for users to implement Secure DFU OTA(over-the-air) while compiling using nRF52840 Solution modules.

(Click on link for Raytac nRF52840 module series)

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

Part C: Combining and merging built files (Will be released in the upcoming article after Part B)

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)

1-Error without public key

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
2-Generate public key file

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:

3-Copy pk[64] code

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
Bluetooth & WiFi module maker based on Nordic nRF54, nRF53, nRF52, nRF7002 solution
BT5.4 &BT5.3 & BT5.2 & BT5.1 Qualified, FCC/IC/CE/Telec/KC/RCM/SRRC/NCC Pre-Certified.
Bluetooth Solution: nRF54, nRF5340, nRF52840, nRF52833, nRF52832, nRF52820, nRF52811, nRF52810, nRF52805, nRF51822
WiFi Solution: nRF7002
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