nRF52 Zephyr DFU

[Vojislav]

Hi,

I am trying to create DFU for nRF52 devices using NCS now that they are supported. I have done this previously with nRF5 SDK and it worked great. Now I do not see any examples in the samples folder of NCS and Zephyr to do such a thing. I found this https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/ug_nrf52.html#fota-upgrades in the documentation but it is not explaining a lot. 

I also read: 
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/ug_bootloader.html

What is the best place to start with DFU for nRF52 devices?

Best regards,
Vojislav.

[Vojislav]

Currnetly I am following guid of zephyr sample: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/samples/subsys/mgmt/mcumgr/smp_svr/README.html

But when I build an app with: west build -b nrf52_pca10040
and then try to sign the build: west sign -t imgtool -- --key root-rsa-2048.pem
like explained in the west sign doc:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/guides/west/sign.html

I get an error:

=== image configuration:
partition offset: 49152 (0xc000)
partition size: 204800 (0x32000)
text section offset: 0 (0x0)
=== signed binaries:
bin: /home/voja/Documents/irnas/ncs/zephyr/samples/subsys/mgmt/mcumgr/smp_svr/build/zephyr/zephyr.signed.bin
Usage: imgtool sign [OPTIONS] INFILE OUTFILE

Error: Invalid value for "-H" / "--header-size": Minimum value for -H/--header-size is 32
FATAL ERROR: command exited with status 2: /home/voja/.virtualenvs/zephyenv/bin/imgtool sign --version 0.0.0+0 --align 4 --header-size 0 --slot-size 204800 --key root-rsa-2048.pem /home/voja/Documents/irnas/ncs/zephyr/samples/subsys/mgmt/mcumgr/smp_svr/build/zephyr/zephyr.bin /home/voja/Documents/irnas/ncs/zephyr/samples/subsys/mgmt/mcumgr/smp_svr/build/zephyr/zephyr.signed.bin

I do not understand what is the problem with signing the image?

[Vojislav]

I was able to update (DFU) nrf52 chip over Android NRF Connect app without signing. 
questions are:
1. is this the preferred way of doing DFU on nrf52 (smp_svr sample) 
2. do you have some samples to show this process?
3. what could be the problem with signing, as I am using NCS v1.2.0?

[Vojislav]

I will move this to separate issue: https://devzone.nordicsemi.com/f/nordic-q-a/61048/signing-zephyr-images---west-sign

[Sigurd]

1) Yes. MCUmgr / smp_svr is the preferred way to do DFU on nRF52 in NCS(nRF Connect SDK).

2) See the bulding and running steps here: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/samples/subsys/mgmt/mcumgr/smp_svr/README.html, for the application you want to DFU with, set CONFIG_BOOTLOADER_MCUBOOT=y

3) Will be answered in the separate case: https://devzone.nordicsemi.com/f/nordic-q-a/61048/signing-zephyr-images---west-sign

[Vojislav]

Hi Sigurd,

Thank you for your reply. This is the approach I already started. Now I am trying to merge smp_svr application with peripheral_uart and get some useful app with buttonless DFU working. 

If you have some suggestions regarding that let me know. 

In the meantime, I am waiting for your answer to the other question in the second issue.

Thank you,
Best regards,
Vojislav.