Hardware-Agnostic IO-Link Protocol Stack for Zephyr RTOS and Bare-Metal Embedded Systems

iolinki is a professional-grade, open-source IO-Link Device Stack (compliant with Spec V1.1.5) designed with complete hardware independence and comprehensive test coverage. Built from the ground up using test-driven development, every component is testable without hardware.

• Hardware-Agnostic: Runs on any platform via clean PHY abstraction
• Test-Driven: 100% mock-based unit testing from day one
• Portable: Zephyr-native with bare-metal compatibility
• Virtual Testing: Conformance verification against virtual IO-Link Master
• Open Source: Transparent, vendor-agnostic implementation

Dual-licensed: GPLv3 or Commercial. Pick the one that matches your product.

• GPLv3 (free, open source) — use, modify, and ship iolinki at no cost, provided your own work that includes it is also released under the GPLv3. Ideal for open-source projects, research, evaluation, and hobby use.
• Commercial license — required only if you ship a closed-source / proprietary product and do not want the GPLv3 copyleft obligations. One-time, royalty-free:
  • Single Developer: €1,399
  • Team (5 seats): €4,699
  • Enterprise / site-wide: custom
  • Includes 12 months of updates + support and up to 8 hours of integration assistance.

Shipping a closed-source product? A commercial license removes the GPLv3 obligations — email andrii@shylenko.com for terms (fast, no-friction). See LICENSE and LICENSE.COMMERCIAL.

sudo apt-get update
sudo apt-get install -y cmake build-essential libcmocka-dev clang-format cppcheck

brew install cmake cmocka clang-format cppcheck

cmake -B build
cmake --build build

cd build
ctest --output-on-failure

To ensure code quality, iolinki uses pre-commit hooks. These hooks run clang-format, cppcheck, ruff, and shellcheck automatically before each commit.

1. Install pre-commit:

   pip install pre-commit

2. Install the git hooks:

   pre-commit install

3. (Optional) Run on all files:

   pre-commit run --all-files

Docker is the primary and recommended environment for running all iolinki tests. This ensures a consistent environment with all tools (CMocka, Cppcheck, Doxygen, Clang-Format) pre-configured.

./run_all_tests_docker.sh

To run tests locally, ensure you have libcmocka-dev installed: -B build -DCMAKE_BUILD_TYPE=Debug cmake --build build cd build && ctest --output-on-failure

### Full Validation Suite (All Platforms + Conformance)
```bash
./test_all.sh

iolinki includes 49 automated conformance tests validating compliance with the IO-Link V1.1.5 specification:

• ✅ State Machine: DLL transitions, ESTAB_COM, fallback behavior (7 tests)
• ✅ Timing: Cycle times, response delays, wake-up timing (5 tests)
• ✅ ISDU Protocol: All mandatory indices + error handling (13 tests)
• ✅ System Commands: Reset, factory restore, Data Storage upload/download (9 tests)
• ✅ Error Injection: Recovery, robustness, edge cases (7 tests)
• ✅ PD / Events / SIO: Process Data, event signalling, SIO fallback (3 tests)
• ✅ Performance: Sustained operation, stress testing (5 tests)

Coverage: 100% of mandatory ISDU indices (0x0010-0x0018, 0x001E, 0x0024), Data Storage (0x0003), state machine transitions, timing requirements, and error handling.

See docs/CONFORMANCE.md for detailed test specifications and coverage matrix.

cmake -B build_bare -DIOLINK_PLATFORM=BAREMETAL
cmake --build build_bare
./build_bare/examples/bare_metal_app/bare_metal_app

iolinki is a first-class Zephyr module: add it to a west workspace, enable it in Kconfig, point it at a UART, and build an IO-Link device. See zephyr/README.md for the full guide (west manifest snippet, Kconfig options, the zephyr,iolink-uart devicetree contract, and the PHY porting note).

Option 1: Docker (Recommended for testing) If you have Docker installed, you can build the Zephyr sample without installing the SDK on your host:

./tools/build_zephyr_docker.sh

Option 2: Local SDK Prerequisite: You must have the Zephyr SDK and tools installed and be running in an initialized Zephyr workspace (or have ZEPHYR_BASE set).

# From your Zephyr workspace root, after adding iolinki as a module
west build -b native_sim modules/lib/iolinki/samples/iolink_device

# For real hardware (UART PHY)
west build -b nucleo_l476rg modules/lib/iolinki/samples/iolink_device -- -DCONFIG_IOLINK_PHY_UART=y

Troubleshooting: If you see west: error: argument <command>: invalid choice: 'build', it means west is installed but the build extensions are not loaded. This happens if you are not in a valid Zephyr workspace.

cmake -B build_bare -DIOLINK_PLATFORM=BAREMETAL
cmake --build build_bare
./build_bare/examples/bare_metal_app/bare_metal_app

Phase 3: Ecosystem & Verification (Current)

The stack is feature-complete for IO-Link V1.1.5, including Process Data, ISDU, Events, and Data Storage. We have achieved 100% core test coverage and established automated IODD generation and strict coding standards (MISRA-oriented).

See ROADMAP.md for detailed development phases.

• ROADMAP.md - Development phases and milestones
• VISION.md - Project mission and approach
• RELEASE_STRATEGY.md - Release workflow and versioning
• INSTALL.md - Detailed installation instructions
• PUPPETEER.md - Agent task mutex workflow (submodule)

Official releases are available on GitHub Releases.

Each release includes:

• Test Results: Complete test suite validation
• Build Artifacts: Pre-compiled examples and test binaries
• Documentation: Updated docs and guides

To create a new release:

git tag -a v0.1.0 -m "Release version 0.1.0"
git push origin v0.1.0

Test-Driven from Ground Zero: All development is built on mocks and abstractions. Every component is testable without hardware. Conformance verification runs against a virtual IO-Link Master on each release.

This project is dual-licensed under the GPLv3 (free, for open-source/GPLv3 use) and a commercial license (for closed-source / proprietary products that cannot accept the GPLv3 copyleft). Shipping a proprietary product? Email andrii@shylenko.com. See LICENSE and LICENSE.COMMERCIAL.

Contributions are welcome! Please see ROADMAP.md for areas where help is needed.