Developer Path

Developer Hub

Codebase map and practical integration workflow for contributors building an open-source Haldex controller, including VW AWD controller and Audi AWD controller integrations across PQ and MQB platforms.

Primary code entry points

src/main.cpp: startup sequence, Wi-Fi policy, API wiring, task bring-up.
src/functions/can/can_bus.cpp: bus abstraction and transmit/receive role mapping.
src/functions/can/can_rx.cpp: decode loops, mapped fallback behavior, frame flow.
src/functions/can/lock_data.cpp: Haldex-facing frame mutation path for inline operation.
src/functions/core/calcs.cpp: lock target calculations and gating.
src/functions/api/api.cpp: endpoint contracts and mutator behavior.
src/functions/storage/storage.cpp: persistence and defaults.
data/ui-dev/app.js: current UI source of interaction behavior.

Gen 5 / MQB implementation map

src/functions/can/can_rx.cpp: generation-aware DBC selection plus Gen 5 RX decode paths.
src/functions/canview/vw_mqb_chassis_dbc.cpp: MQB decoded signal catalog used for mapped inputs and CAN View.
src/functions/canview/canview.cpp: decoded-signal exposure and Haldex frame inspection in the UI tooling path.
src/functions/can/lock_data.cpp: Haldex-side frame shaping for non-standalone Gen 5 operation.
src/functions/io/frames.cpp: generation-specific standalone frame shaping, including Gen 5 support.

Local development flow

Build firmware and resolve warnings/errors before behavior changes.
Validate API payload behavior with status-readback after writes.
Test UI flows against real endpoints and failure responses.
Capture logs and CAN traces for regressions before tuning changes.
Update docs and changelog in the same change set when behavior shifts.

Integration tips

Always treat firmware as the source of truth and re-pull /api/status after writes.
Avoid frontend-side duplicate calculation logic for lock requests.
Respect safety overrides and debug-capture forced-stock behavior.
Keep API compatibility in mind when renaming or restructuring payload fields.

Project channels

Try the OpenHaldex Firmware Demo

Preview the real OpenHaldex firmware UI in your browser with simulated live CAN traffic and interactive pages for tuning, diagnostics, logs, setup, and OTA workflows.

Open firmware demo