USBX

Internal Azure DevOps mirror of Eclipse ThreadX USBX (upstream: eclipse-threadx/usbx), imported here for testing before being exported as a public middleware module to GitHub.

This is the import side only — see ThreadX_AzureImport.sh --component usbx in Middlewares_Handler. The export step (Azure DevOps → GitHub, with its own testing/approval logic) is separate and not yet built.

This file itself is regenerated (rendered from README_ThreadXDefault.md) by every import run — don't hand-edit it here, edit README_ThreadXDefault.md next to ThreadX_AzureImport.sh instead.

---

Branch & repository layout

Everything lives on a single anchor branch (master). One real commit per Eclipse ThreadX USBX version, tree replaced wholesale each time, commit subject naming its normalized version (e.g. USBX 6.4.2 — see Versioning below), commit body naming the raw upstream tag. No git tags are created here — this is the Azure DevOps staging side only; tagging happens later, during the separate export step that promotes a tested/approved version to the public GitHub middleware repo.

<repo root>
├── CMakeLists.txt   auto-generated every version (see below) — do not hand-edit
├── README.md        this file
└── USBX/      the release as upstream tags it, resolvable submodules vendored
                     in place, no .git / .gitmodules / .gitignore anywhere
    ├── CMakeLists.txt     upstream's own — defines the `usbx` library target
    ├── common/            the portable component source
    ├── ports/             per-architecture / per-toolchain ports (where the component has any)
    └── ...

Source

ThreadX_AzureImport.sh discovers versions via the GitHub Releases API (drafts and prereleases ignored). Each version is fetched with a shallow git clone --branch <upstream tag>, the checked-out tag is verified to be exactly that tag, and the resulting tree is copied into USBX/ as-is.

Versioning

Upstream eclipse-threadx/usbx tags are not a clean X.Y.Z — they carry an extra build tag and/or an _rel/letter suffix, and the format has changed over time. ThreadX_AzureImport.sh normalizes every upstream tag before importing:

Upstream tag example	Normalized version
v6.4.1_rel	6.4.1
v6.4.2.202503_rel	6.4.2 (build tag 202503 dropped)
v6.4.4.202503a	6.4.4
v.6.4.4.202503_rel	6.4.4 (a "v." typo variant, seen on some netxduo tags)
v6.0_rel	6.0.0 (X.Y only — patch synthesized as 0)

Where two upstream tags normalize to the same version (e.g. a build-tag revision that only bumped internal metadata), the release with the later publish date wins — the older one is not imported at all.

Submodules

eclipse-threadx/netxduo references at least one test-only submodule in its own .gitmodules that has been observed broken in some releases (see upstream issue netxduo#310). Submodule resolution here is therefore best-effort: a failure is logged as a warning, not treated as a reason to skip the version — what matters for a middleware consumer is the library source, not upstream's own test scaffolding. Every submodule that did resolve is fully flattened: every .git entry, .gitmodules and .gitignore file is stripped before committing — no submodules, no gitlinks, no dependency on any other repository.

CMake support requirement — versions without a usable target are not imported at all

The generated root CMakeLists.txt only wraps upstream's own USBX/CMakeLists.txt, so a version is imported only if that file exists and defines the usbx library target (add_library(usbx ...), or project(usbx ...) + add_library(${PROJECT_NAME} ...) as current upstream does). Anything else is skipped entirely — no commit, nothing published for it in this repo.

---

Building against it — the generated CMakeLists.txt

The root CMakeLists.txt in this repo does not invent any library — it just add_subdirectory()s USBX/, whose upstream CMakeLists.txt defines the usbx target (plus its azrtos::usbx alias).

Upstream requires two variables to be set before the module is added — they select the port under USBX/ports/<arch>/<toolchain>/:

• THREADX_ARCH — e.g. cortex_m0, cortex_m4, cortex_m7, cortex_m33, ...
• THREADX_TOOLCHAIN — e.g. gnu, ac6, iar.

Vendor this repo (e.g. as a submodule at Middlewares/USBX), then from your own top-level CMakeLists.txt:

set(THREADX_ARCH "cortex_m4")
set(THREADX_TOOLCHAIN "gnu")

add_subdirectory(Middlewares/USBX)
target_link_libraries(${PROJECT_NAME}
    PRIVATE
        usbx
)

Notes on the upstream target

• Dependencies between components. Every component other than ThreadX itself links against azrtos::threadx (and some, e.g. NetX Duo and LevelX, optionally against azrtos::filex) — add the ThreadX module first, then the components that depend on it.
• User configuration header. Each component looks for an optional <component>_user.h (e.g. tx_user.h, nx_user.h) — enable it through upstream's own CMake options / defines (see the component's upstream documentation).
• Upstream's file may also declare install() rules — harmless unless you run cmake --install on your own project.

---

Notes

• A brand-new repo (or an existing repo that's just missing the master branch, e.g. one still carrying the old main/Content layout) gets a real Initial commit containing just this README.md, pushed immediately when the branch is created — so it's never left with zero commits even if the first version afterwards fails or every available version is skipped. The first version actually imported then wholesale-replaces that with the full tree, same as every later version. Other branches are left untouched.
• No git tags are created by this importer — tagging happens later, during the separate export step.
• Re-running the import is idempotent — a version already present as a commit on master (matched by its commit subject, USBX <version>) is skipped.

---

Authors

• Mr.Nobody — embedbits.com