MCUBOOT with nrf9161-sica

RE: MCUBOOT with nrf9161-sica

Øyvind — Tue, 26 May 2026 12:51:29 GMT

Are you using Sysbuild in your application? Our AI chatbot provides the following explanation on MCUboot and Sysbuild:

MCUboot and Sysbuild

Sysbuild and MCUboot are closely integrated in the nRF Connect SDK. Here's how they relate:

Sysbuild manages MCUboot as an extra image

Sysbuild is a higher-level build system that can combine multiple build systems — including MCUboot — into a single hierarchical build. MCUboot is one of the pre-made images available in nRF Connect SDK that can be pulled into the build via Sysbuild. [Sysbuild overview]

Enabling MCUboot via Sysbuild

To add MCUboot to your application, you simply enable it in the sysbuild.conf file in your project root:

SB_CONFIG_BOOTLOADER_MCUBOOT=y

This single option instructs Sysbuild to build MCUboot alongside your application, flash both images, and link your application as an MCUboot-bootable image. [Adding MCUboot]

Configuring MCUboot through Sysbuild

Sysbuild Kconfig options (prefixed with SB_CONFIG_) generally override MCUboot's own Kconfig options, ensuring a coherent environment for the entire system. [MCUboot config]

To apply MCUboot-specific configuration, create a sysbuild/mcuboot.conf file in your project. For example, to disable serial logging in MCUboot:

CONFIG_SERIAL=n

[Adding MCUboot]

Key roles MCUboot can play (configured via Sysbuild)

| Role | Sysbuild options | |---|---| | Immutable first-stage bootloader | SB_CONFIG_BOOTLOADER_MCUBOOT=y | | Upgradable second-stage bootloader | SB_CONFIG_BOOTLOADER_MCUBOOT=y + SB_CONFIG_SECURE_BOOT_APPCORE=y | | Firmware loader mode | SB_CONFIG_BOOTLOADER_MCUBOOT=y + SB_CONFIG_MCUBOOT_MODE_FIRMWARE_UPDATER=y |

[MCUboot in NCS]

Configuration rules

Importantly, Sysbuild can configure MCUboot and the application, but MCUboot and the application cannot configure Sysbuild or each other. This provides a clear separation of ownership. [Sysbuild blog]

Kind regards,
Øyvind

RE: MCUBOOT with nrf9161-sica

Uri Rotshtein — Sat, 23 May 2026 18:25:33 GMT

The application runs perfectly on my custom board when compiled without MCUboot. However, when I enable MCUboot, the boot process hangs right when it is supposed to jump to my application. Note: I haven't tested this on the official dev board yet.

RE: MCUBOOT with nrf9161-sica

Øyvind — Tue, 28 Apr 2026 07:22:23 GMT

[quote user="oys"]are you able to build for nrf9160dk/nrf9160/ns and test the same application on that board? [/quote]

Does the nRF9160DK fail with MCUBOOT as well?

RE: MCUBOOT with nrf9161-sica

Uri Rotshtein — Mon, 27 Apr 2026 18:45:41 GMT

Yes, I can build my application and it is running perfect without any error or warning during the build. Once I tried to add the MCUBOOT to support 2 images I started to had the problem. Without the MCUBOOT every thing is working fine

RE: MCUBOOT with nrf9161-sica

Øyvind — Mon, 27 Apr 2026 12:32:05 GMT

Hello,

are you able to build for nrf9160dk/nrf9160/ns and test the same application on that board?

Are you getting any warnings/errors in the build log while building for your custom board? How is you custom board configured?

Kind regards,
Øyvind