Abstraction Layers for Zephyr RTOS - Version 4.0.0 Released

microej_official · October 19, 2026, 7:38am

Hi everyone,

We are pleased to announce the release of the Abstraction Layers version 4.0.0 for Zephyr RTOS.

The git repository contains the Abstraction Layers and 3 VEE Port samples for the following boards:

It can be customized for any board supported by Zephyr by following How to configure a new
board section of the README.

Here are the major changes:

Migration to Zephyr version 4.4.2.
Add the Central Role of the Bluetooth foundation library: scanning, connection,
pairing, GATT read/write, and notifications/indications.
Build the Crypto (formerly Security) and
SSL foundation libraries on Mbed TLS 4.1 and TF-PSA-Crypto.
Use picolibc as the C library instead of newlib.
Select the target board with a single Gradle property, -Pveeport.board=<name> (mimxrt1170, mcxn947, nrf54l15).
Configure the boards with Zephyr’s own mechanisms (board .conf and .overlay files, board extensions) instead of per-board CMake files.
Update the following foundation libraries inside VEE Port Samples:
- MicroEJ SDK → 1.8.0
- Bluetooth → 3.0.0
- NET Pack → 15.0.1
- Crypto → 2.1.0

Some cryptographic algorithms are no longer available in the Crypto and SSL foundation libraries, because Mbed TLS 4.1 and TF-PSA-Crypto do not provide them:

The DES and DESede ciphers.
The secp192r1, secp192k1, secp224r1 and secp224k1 elliptic curves.
The TLS 1.2 RSA, RSA-PSK, DHE and static ECDH key exchanges.

A complete list of changes introduced in this release is available in the changelog

github.com/MicroEJ/VEEPort-Zephyr

CHANGELOG.md

4.0.0

# Changelog
   
All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [4.0.0] - 2026-10-09

### Added

  - Add Bluetooth Central role support (scanning, connection, pairing, GATT read/write, and notifications/indications).
  - Add a `System.arraycopy()` throughput check to the Core validation testsuite, with a configurable minimum throughput for each of the four copies it measures.

### Changed

  - Update Zephyr to 4.4.2.
  - Update MicroEJ SDK to 1.8.0.
  - Update to Bluetooth 3.0.0.
  - Update to NET Pack 15.0.1.

This file has been truncated. show original

The VEE Port source code is available on GitHub: GitHub - MicroEJ/VEEPort-Zephyr at 4.0.0 · GitHub

List of foundation libraries now supported by Zephyr’s Abstraction Layers:

Migrating from 3.1.0

Remove the Zephyr patches of version 3.1.0. From the bsp directory, with the Python virtual environment activated, run west patch clean.
- Version 3.1.0 patched the Zephyr sources, and west update refuses to move a patched Zephyr tree to the new version.
- This command restores the Zephyr tree with git checkout . and git clean -d -f -x: any change of your own in bsp/zephyr is lost.
Run scripts/setup.sh (or scripts/setup.bat) again. It updates Zephyr to 4.4.2, the Python packages, and the Zephyr SDK, then applies the patches of version 4.0.0.
Run bsp/zephyr-app/vee/scripts/clean.sh (or clean.bat) script, so that the next build starts from the new Zephyr version.
Select the board with -Pveeport.board=<name> (or veeport.board=<name> in gradle.properties). Gradle now derives the Zephyr board and the MicroEJ Architecture from this property:
- In bsp/zephyr-app/vee/scripts/set_project_env.sh (and .bat), remove the BOARD value you set for your board. A hard-coded value overrides the board selected by Gradle.
- In gradle/libs.versions.toml, remove the architecture group and name you set for your board. Only the architecture version is read from this file.
If you added your own board:
- Add it to the board list in gradle/boards.gradle.kts, with its Zephyr board name, its MicroEJ Architecture, and its VEE Port group. -Pveeport.board accepts only the names of this list.
- Move the content of its bsp/zephyr-app/main/boards/<board>.cmake file to the .conf and .overlay files of the board. This file is no longer read.
- Rename the CONFIG_MICROEJ_SECURITY options to CONFIG_MICROEJ_CRYPTO. Zephyr stops the build on an unknown option.
If your application uses one of the removed algorithms listed above, switch to a supported one, such as AES, secp256r1, or an ECDHE key exchange.

Happy coding!
The MicroEJ Team.