Differences in BLE Controller Initialization logs between throughput sample and throughput with Single-Slot DFU Integration

RE: Differences in BLE Controller Initialization logs between throughput sample and throughput with Single-Slot DFU Integration

lammobile — Thu, 28 May 2026 10:09:46 GMT

Hi Hung,

Thank you for the information. That makes sense. Thanks a lot.

RE: Differences in BLE Controller Initialization logs between throughput sample and throughput with Single-Slot DFU Integration

Hung Bui — Thu, 28 May 2026 10:01:12 GMT

Hi Lam,
I think you pinpointed the cause. Fwloader ipc image should be in cpurad_slot1. The configured you had earlier made the app to use the BLE controller of the Fwloader instead of its own (slot 0).

I got some info from R&D, which related to another ticket but could be relevant to you:

The firmware loader mode (single slot) does not support multiple images (from the bootloader perspective). That's why if you enable it on nRF54H20, the "merged slot" approach is automatically enabled.

The partitioning of the BLE-enabled application should be fairly similar to what you can find in the Direct XIP (merged_slot suffix) configuration of the smp_svr sample as well as the A/B sample:

- slot0_partition: the merged app+radio application partition

- cpuapp_slot0_partition: the main application partition

- cpurad_slot0_partition: the main radio partition

- slot1_partition: the merged app+radio FW loader partition

- cpuapp_slot1_partition (also: fw_loader_partition): the FW loader application partition

- cpurad_slot1_partition: the FW loader radio partition (note: if the main application uses radio, the FW loader partition is no longer the "cpurad_slot0_partition" but "cpurad_slot1_partition". This is a consequence of a logic inside the soc.c that tries to find the proper radio slot for a given application image to boot. This change must be also applied inside the sysbuild/fw_loader_ipc_radio.overlay file so the code,partition is set to point the correct partititon).

When the radio is merged with the application, the application image might not be the last one in the merged partition. If so, please adjust the MCUBOOT_IMAGES_ROM_END_OFFSET_AUTO Kconfig value by replacing the "single_slot" image name with the appropriate radio image name.

RE: Differences in BLE Controller Initialization logs between throughput sample and throughput with Single-Slot DFU Integration

lammobile — Thu, 28 May 2026 03:16:37 GMT

Hi Hung,

Good news: The issue is resolved. I updated the partition labels as follows:

Changed cpurad_slot0_ipc_radio_partition $-->$ cpurad_slot0_partition (under slot0_partition: 256KB for ipc_radio to interface with the app).
Changed cpurad_slot0_partition $-->$ cpurad_slot1_partition (under slot1_partition to configure ipc_radio for fw_loader).

Is there a defined naming convention or policy for these partition labels?

RE: Differences in BLE Controller Initialization logs between throughput sample and throughput with Single-Slot DFU Integration

Hung Bui — Wed, 27 May 2026 12:29:28 GMT

Hi Lam,
Thanks for the instruction. I have reproduced what you observed here.
I'm checking with the team to get more insight.

My understanding is that when you enable fw_loader with BLE on nRF54H it will add a controller to the radio core (in addition to the main application's BLE controller). And the way the radio core booting may be slightly changed (for example log configuration) and you may see different log.

Do you see any change in the BLE behavior when testing with throughput sample or other BLE sample ?

RE: Differences in BLE Controller Initialization logs between throughput sample and throughput with Single-Slot DFU Integration

lammobile — Wed, 27 May 2026 04:48:21 GMT

Hi Hung,

I tried with peripheral_uart, and the behavior changed similarly to the throughput example when adding DFU single_slot.

devzone.nordicsemi.com/.../8623.peripheral_5F00_uart.zip

1. build_app_only.bat – This build includes only the app and netcore. The log is shown below.

1.1 Build

D:\ncs\v3.3.0\peripheral_uart>build_app_only.bat
D:\ncs\v3.3.0\peripheral_uart>west build -d build_app_only -b nrf54h20dk/nrf54h20/cpuapp

1.2 Log

*** Booting My Application v3.3.0-6f99e1462c81 ***
*** Using nRF Connect SDK v3.3.0-ba167d9f3db4 ***
*** Using Zephyr OS v4.3.99-fd9204a02d52 ***
Starting Nordic UART service sample
I: 10 Sectors of 4096 bytes
I: alloc wra: 0, fc0
I: data wra: 0, 0
I: HW Platform: Nordic Semiconductor (0x0002)
I: HW Variant: nRF54Hx (0x0004)
I: Firmware: Standard Bluetooth controller (0x00) Version 39.32003 Build 4270654547
I: No ID address. App must call settings_load()
I:
App v3.3.2 build time: May 27 2026 11:14:38

I: Bluetooth initialized
I: HCI transport: IPC
I: Identity: CA:12:CA:03:D3:7E (random)
I: HCI: version 6.2 (0x10) revision 0x40a3, manufacturer 0x0059
I: LMP: version 6.2 (0x10) subver 0x40a3
I: Advertising successfully started

2. build_boot_req.bat – This build integrates single_slot as well. The log is shown below.

In this build, I used the dfu_application.zip file to update. The file size is ~1.5MB, similar to the app and netcore image merge strategy, and the update was successful. However, the log for the IPC radio image differs from build_app_only.

2.1 Build

west build -b nrf54h20dk/nrf54h20/cpuapp -T ./sample.dfu.single_slot.fw_loader_update.fw_loader_entrance_boot_req.nrf54h20

D:\ncs\v3.3.0\peripheral_uart>build_boot_req.bat
D:\ncs\v3.3.0\peripheral_uart>west build -d build_boot_req -b nrf54h20dk/nrf54h20/cpuapp --sysbuild -- -DSB_CONFIG_FIRMWARE_LOADER_UPDATE=y -DFILE_SUFFIX=boot_req -Dinstaller_DTC_OVERLAY_FILE="${ZEPHYR_NRF_MODULE_DIR}/samples/dfu/single_slot/boards/nrf54h20dk_nrf54h20_cpuapp_boot_req.overlay" -Dinstaller_CONFIG_INSTALLER_FW_LOADER_ENTRANCE_BOOT_REQ=y -Dinstaller_CONFIG_NRF_MCUBOOT_BOOT_REQUEST=y -Dinstaller_CONFIG_IMG_MANAGER=y -Dinstaller_CONFIG_REBOOT=y

2.2 Log

*** Booting My Application v3.3.0-6f99e1462c81 ***
*** Using nRF Connect SDK v3.3.0-ba167d9f3db4 ***
*** Using Zephyr OS v4.3.99-fd9204a02d52 ***
Starting Nordic UART service sample
I: 10 Sectors of 4096 bytes
I: alloc wra: 0, f10
I: data wra: 0, 70
W: Controller to host flow control not supported
W: opcode 0xfc01 status 0x01
W: Vendor HCI extensions not available
I: No ID address. App must call settings_load()
I:
App v3.3.2 build time: May 27 2026 11:20:56

I: Bluetooth initialized
W: Read Static Addresses command not available
I: HCI transport: IPC
I: Identity: D1:2C:1C:C0:A6:E5 (random)
I: HCI: version 6.2 (0x10) revision 0x40a3, manufacturer 0x0059
I: LMP: version 6.2 (0x10) subver 0x40a3
I: Advertising successfully started

== dfu_application.zip ==


*** Booting My Application v3.3.0-6f99e1462c81 ***
*** Using nRF Connect SDK v3.3.0-ba167d9f3db4 ***
*** Using Zephyr OS v4.3.99-fd9204a02d52 ***
Starting Nordic UART service sample
I: 10 Sectors of 4096 bytes
I: alloc wra: 0, f00
I: data wra: 0, 80
W: Controller to host flow control not supported
W: opcode 0xfc01 status 0x01
W: Vendor HCI extensions not available
I: No ID address. App must call settings_load()
I:
App v3.3.3 build time: May 27 2026 11:28:09

I: Bluetooth initialized
W: Read Static Addresses command not available
I: HCI transport: IPC
I: Identity: E2:7B:9A:68:8E:FE (random)
I: HCI: version 6.2 (0x10) revision 0x40a3, manufacturer 0x0059
I: LMP: version 6.2 (0x10) subver 0x40a3
I: Advertising successfully started

RE: Differences in BLE Controller Initialization logs between throughput sample and throughput with Single-Slot DFU Integration

lammobile — Tue, 26 May 2026 16:21:34 GMT

Hi Hung,
Please build throughput_dfu_single_slot using the following command:
* I'm running a build command on a Windows PC

west build -p -b nrf54h20dk/nrf54h20/cpuapp -T ./sample.dfu.single_slot.fw_loader_update.fw_loader_entrance_boot_req.nrf54h20

RE: Differences in BLE Controller Initialization logs between throughput sample and throughput with Single-Slot DFU Integration

Hung Bui — Tue, 26 May 2026 13:01:09 GMT

Hi Lam,

It's quite strange that adding single slot DFU can cause the application to change behavior.
If you try to build another application , for example peripheral_hr, do you see the same change in the log ?
I tried to build the sample you provided throughput_dfu_single_slot but got the following error:

Do you have anything else need to be set or include when building ?