Hardware tdd
Use when planning tests for Arduino, ESP32, ESP32-S3, Pico, or Pico W firmware; deciding what can run off-target; using Wokwi or simulation; writing host fakes; or accepting a physical hardware feature without confusing compile proof with system proof.From its SKILL.md
npx -y skills add wedsamuel1230/arduino-skills --skill hardware-tddAssembled from the repository path, not quoted from the project. Check it against their README if it does not work.
One thing to look at
- 20 stars20 stars. Stars are a popularity signal and not a quality one, but at this level it is likely that nobody has read this closely except its author, and you would be relying on your own review.
SKILL.md
3.3 KB, as published. Nobody here has run it
Hardware TDD
Build the test ladder before claiming a feature is complete. Pure behavior can often be tested off-target; voltage, pin mux, timing under load, and physical assembly still require target evidence.
Intake
Record exact board/revision, framework/toolchain, hardware invariants, safety inhibits, simulator model, available instruments, test fixtures, and the proof stage required by the user.
Process
- Turn requirements into observable behavior and safety invariants.
- Write host tests for pure C/C++ logic using fakes for time, serial, sensors, and actuators. Keep hardware adapters thin.
- Use Wokwi or another simulator only for peripherals and timing that its model actually represents; record model limitations.
- Run an exact-board compile and static checks with the selected toolchain.
- Create a one-change target checklist: power-off continuity, controlled power-up, input observation, output inhibit, reset/recovery, and logs.
- Ask a physical gate for measurements, photos, or serial output. Do not infer target success from a host test or compile log.
- Record failures as evidence and keep the next test bounded.
Test matrix
| Layer | Example | Proves | Does not prove |
|---|---|---|---|
| Host | debounce/state/packet parser | deterministic logic | pin voltage or wiring |
| Simulation | modeled sensor/LED/UART | modeled interactions | regulator, clone, EMI, thermal behavior |
| Build | exact FQBN/environment | source and dependency compile | upload or behavior |
| Target | serial, meter, scope, photo | observed hardware behavior | field reliability unless loaded |
| System | integrated load/failure case | requirement under scenario | future deployment safety |
Anti-rationalization
| Shortcut | Response |
|---|---|
| "The unit test passed." | Keep all physical and system stages open. |
| "Wokwi matches the board." | List what the model omits and verify those items on hardware. |
| "The sketch compiled." | Require upload identity and target observations separately. |
| "The photo proves it works." | Require board identity, measurement context, and observed result. |
| "Mark it done and test later." | Keep the loop item blocked or needs-review until evidence exists. |
Verification
- Every requirement maps to a test, proof stage, and artifact path.
- Host/simulation/build/target/system results are labeled separately.
- Physical-only steps emit the concrete
Physical gateformat fromembedded-project-loop. - Failed and unverified cases remain visible in the report.
Shared output contract
Use the shared Arduino skill contract: state assumptions, required tools and versions, implementation steps, tests/evidence by proof stage, known limitations, and recovery/security notes.