Zephyr Module

heliaCORE is a first-class Zephyr module. Add it to your west.yml, enable the required kernel groups, and build your board application.

Prerequisites

Start with a working board application and matching target/compiler settings. See Requirements before choosing source or prebuilt kernels.

1. Add to west.yml

manifest:
  remotes:
    - name: ambiqai
      url-base: https://github.com/AmbiqAI
  projects:
    - name: ns-cmsis-nn
      remote: ambiqai
      revision: v7.39.2 # x-release-please-version
      path: modules/lib/ns-cmsis-nn

Then west update.

2. Enable in your app’s prj.conf

CONFIG_CMSIS_NN=n
CONFIG_NS_CMSIS_NN=y
CONFIG_NS_CMSIS_NN_ACTIVATION=y

That’s the source build — Zephyr will compile the kernels with your project’s toolchain. The CMSIS-NN headers are added to the include path automatically, and the kernels are linked into your image.

Minimal setup for First kernel

The activation option brings in its support group. This configuration leaves floating-point kernels disabled. heliaCORE’s Zephyr module requires Cortex-M and cannot be enabled alongside upstream CONFIG_CMSIS_NN=y. If another component selects that upstream option, resolve that dependency before continuing.

Add more kernels when needed

Select individual CONFIG_NS_CMSIS_NN_* groups in menuconfig. To enable all groups, use CONFIG_NS_CMSIS_NN_ALL=y; this also implies FP32 and FP16 where the target supports it. For explicit floating-point selection, use CONFIG_NS_CMSIS_NN_ENABLE_F32=y or CONFIG_NS_CMSIS_NN_ENABLE_F16=y and check target dependencies in menuconfig.

3. (Optional) Use the prebuilt .a

If you want to skip the kernel rebuild and use the GCC-built archive from the GitHub Release:

CONFIG_NS_CMSIS_NN=y
CONFIG_NS_CMSIS_NN_USE_PREBUILT=y
CONFIG_NS_CMSIS_NN_PREBUILT_PATH="/path/to/extracted/ns-cmsis-nn-<cpu>-<toolchain>-<version>"

CONFIG_NS_CMSIS_NN_PREBUILT_PATH should point at the extracted tarball directory (the one containing lib/libns-cmsis-nn.a and include/). The module wires it in as an IMPORTED STATIC library and applies the include directories via zephyr_include_directories.

Toolchain alignment

Your Zephyr toolchain must produce ABI-compatible objects with the archive’s CPU/FPU flags, float ABI, and calling convention. Prefer the release tarball whose toolchain stamp matches your Zephyr compiler.

4. Build and verify

Build and flash using your existing Zephyr board configuration. Keep its board name, overlays, and application-specific arguments. For a configured build, west build -d build rebuilds the application; west flash -d build uses its configured runner.

After west build, confirm Zephyr picked up the module and selected the path you expected:

grep -E '^CONFIG_NS_CMSIS_NN' build/zephyr/.config

For a source build, the generated build graph should compile heliaCORE sources from modules/lib/ns-cmsis-nn/Source/. For a prebuilt build, the final link command should include the extracted lib/libns-cmsis-nn.a from CONFIG_NS_CMSIS_NN_PREBUILT_PATH.

If the module does not appear in .config, check that the west.yml path matches the module location and that your application enables CONFIG_NS_CMSIS_NN=y.

Expected configuration

The generated .config contains CONFIG_NS_CMSIS_NN=y and CONFIG_NS_CMSIS_NN_ACTIVATION=y for the minimal source example. It does not enable the upstream CONFIG_CMSIS_NN library.

Symptom	Check
Module option unavailable	Confirm the module is in the west workspace, the target is Cortex-M, and upstream CMSIS-NN is disabled.
Float option unavailable	Check its target dependencies in menuconfig.
Archive feature mismatch	Select an archive containing the requested features or return to source mode.

Source-build configuration ownership

Zephyr’s Kconfig symbols remain authoritative, including the float-width settings. The adapter updates both the CMake cache and normal variables from Kconfig, so a standalone -DARM_NN_ENABLE_F16=ON cannot bypass a Kconfig dependency. Optimization comes from Zephyr’s optimization_fast setting; standalone and NSX optimization options do not override it. Float and inline requantize definitions remain visible to application translation units through Zephyr’s global definition API.

The shared source mapping preserves Zephyr’s group order and empty selection: when no group is enabled, no sources are attached. This is not the standalone or NSX convention where an empty group list selects all groups. Prebuilt mode keeps its existing manifest checks and does not apply source-build optimization.

For an application using the repository’s armclang toolchain, set CMP0123 to NEW after cmake_minimum_required() and before enabling C/C++ with project(). The module is included too late to change compiler initialization. See the NSX application setup and manual check for the policy example; that modeled fixture does not establish a Zephyr board build. Use the policy setup required by your actual Zephyr/toolchain integration.

Reference

• Module manifest: zephyr/module.yml
• Kconfig: zephyr/Kconfig
• CMake glue: zephyr/CMakeLists.txt

Next step

Run First kernel to verify an actual kernel result on your target. Keep activation kernels enabled for that example.