nrf_desktop application can't off the b0 bootloader

[Hannibalhz]

Dear Nordic Engineers

Our customers use the nrf_desktop  application to develop their product.

 They use the NCS 2.0.0\nrf\applications\nrf_desktop and build project on the nrf52840dk_nrf52840.

It looks normal. The program can run.

They would like off the b0 bootloader. So I went to their company to help them.

I read this link:https://developer.nordicsemi.com/nRF_Connect_SDK/doc/2.0.0/nrf/applications/nrf_desktop/README.html

The bo bootloader can set the following configs to open/off the b0 bootloader.
CONFIG_SECURE_BOOT
CONFIG_BUILD_S1_VARIANT
CONFIG_FW_INFO
CONFIG_FW_INFO_FIRMWARE_VERSION
CONFIG_SB_SIGNING_KEY_FILE

So I off this config on nrf\applications\nrf_desktop\configuration\nrf52840dk_nrf52840\prj.conf.

I rebuilt the project and it reports some errors. I found that it needs off "CONFIG_DESKTOP_CONFIG_CHANNEL_DFU_ENABLE".

Then the project can be built.I downloaded the program to PCA10056(V1.0.0). The program can't run. 

I review nrf_desktop\configuration\nrf52840dk_nrf52840\prj.conf of NCS V1.9.1 and NCS V2.0.0. Their difference is the following configs.

CONFIG_SECURE_BOOT
CONFIG_BUILD_S1_VARIANT
CONFIG_FW_INFO
CONFIG_FW_INFO_FIRMWARE_VERSION
CONFIG_SB_SIGNING_KEY_FILE

CONFIG_DESKTOP_CONFIG_CHANNEL_DFU_ENABLE

Do I need off other config? Please give me some good suggestions.

Best regards.

[dejans]

Hi,

I have tried your provided sample nrf_desktop.zip. I have noticed the presence of -DBOARD_ROOT:STRING="e:/NCS/my_samples/serial_lte_modem" and app.overlay. In addition, your prj.conf has had CONFIG_SECURE_BOOT=n, but does not have CONFIG_DESKTOP_CONFIG_CHANNEL_DFU_ENABLE=n. Is there any reason for this?
When I flashed your project, LEDs were not turned on.

I have also tried your merged1.hex and merged2.hex. Merged1.hex does turn LED1 ON and LED2 ON/OFF, but merged2.hex does not turn ON any LEDs.

Best regards,
Dejan

[Hannibalhz]

Dear Dejans

1. You can delete my build files and rebuild a new build project for nrf52840dk.

2. "CONFIG_DESKTOP_CONFIG_CHANNEL_DFU_ENABLE" is a default config of nrf_desktop.

Its default config is "CONFIG_DESKTOP_CONFIG_CHANNEL_DFU_ENABLE=y".

So you should look for it to prj.conf's line 60.

3. Yes, merged2.hex does not turn ON any LEDs and you can't use phone or PC's bluetooth scan advertising of DK.

I tried to three PCs to build and test nrf_desktop for this problem. This problem reappears every time.

So I think this problem is a bug of NCS 2.0.0.

4. You can use your PC and PCA10056(v1.0.0) to copy this way.

You only close "CONFIG_DESKTOP_CONFIG_CHANNEL_DFU_ENABLE" and "CONFIG_SECURE_BOOT" in your prj.conf of nrf_desktop.

Then build the project and download program to PCA10056(v1.0.0).

This problem will recurrence.

Best regards.

[dejans]

Hi,

I have tested the nrf_desktop sample again. I observed as well the LEDs behavior and I could reproduce the sttus of the LEDs. With relevant two options (CONFIG_DESKTOP_CONFIG_CHANNEL_DFU_ENABLE and CONFIG_SECURE_BOOT) enabled, LEDs are turned ON, but with two options disabled LEDs are not turned ON. This is expected as shown in the LED stream module configuration. CONFIG_DESKTOP_CONFIG_CHANNEL_DFU_ENABLE=n disables LEDs.

Best regards,
Dejan

[Hannibalhz]

Dear Dejans

If set  "CONFIG_DESKTOP_CONFIG_CHANNEL_DFU_ENABLE=n" and "CONFIG_SECURE_BOOT=y",the project will not be build.

And close "CONFIG_DESKTOP_CONFIG_CHANNEL_DFU_ENABLE",the program will not have advertising.

So how to close b0 bootloader?

Best regards.

[dejans]

Hi,

The advertising should not be affected.

Can you verify that you will not have advertising when you turn off b0 bootloader?

Best regards,
Dejan