apps/carTui is the terminal counterpart to Car UI. It provides a curses home menu and navigable automotive destinations while using reusable views under frontends/tui.

Included destinations include:

Off-road navigation: heading, pitch, roll, acceleration, angular velocity, GPS state, calibration, and relative-heading reset.
Vehicle telemetry: RPM, speed, boost, temperatures, pedal/load values, pressures, airflow, fuel, and module voltage.
Radio: FM broadcast, scanner, AM aviation, and FM weather-band receivers with tuning, presets, and receiver telemetry.

Telemetry architecture

Car TUI is a consumer of the OpenRoadCode message bus. Navigation and vehicle state are supplied by producer services rather than by constructing navigation or OBD-II hardware inside the TUI.

Diagram key App / UI Service / runtime Controller / domain Messaging / contract Protocol / hardware External / input

flowchart LR
    nav["Navigation service"] --> broker["ZeroMQ broker"]
    auto["Automotive service"] --> broker
    broker --> dispatcher["MessageDispatcher"] --> tui["Car TUI"]
 
    classDef orcApp fill:#dbeafe,stroke:#2563eb,color:#172554;
    classDef orcService fill:#ede9fe,stroke:#7c3aed,color:#2e1065;
    classDef orcController fill:#dcfce7,stroke:#16a34a,color:#14532d;
    classDef orcMessage fill:#ffedd5,stroke:#ea580c,color:#7c2d12;
    classDef orcAdapter fill:#fee2e2,stroke:#dc2626,color:#7f1d1d;
    classDef orcExternal fill:#f3f4f6,stroke:#6b7280,color:#1f2937;
    class nav,auto orcService;
    class broker,dispatcher orcMessage;
    class tui orcApp;

NavigationBusState and VehicleBusState cache the latest decoded snapshots for the UI thread.

Start Car TUI

From the repository root:

python3 -m apps.carTui.main

Use --config PATH to select a runtime file when needed.

Full simulated telemetry stack

A simulation runtime should select simulated sources in the producer services. The application itself follows the same subscriber path used with physical hardware.

Start the broker:

python3 -m messaging.zeromq.broker_cli

Start simulated navigation:

python3 -m services.navigation.navigation_service_cli \

--config config/runtime_simulation.toml

Start simulated automotive telemetry:

python3 -m services.automotive.automotive_service_cli \

--config config/runtime_simulation.toml

Then start Car TUI:

python3 -m apps.carTui.main

This exercises the same ZeroMQ contracts, dispatcher, shared state, and TUI rendering that will be used with physical sources.

Units

OpenRoadCode telemetry contracts remain SI-normalized. Car TUI converts values only for presentation using common.units.

The unit preference is shared by the Navigation and Vehicle screens. Press u on either screen to toggle between metric and imperial presentation. The underlying NavigationBusState, VehicleBusState, and ZeroMQ messages are not modified.

Controls

Home controls are arrow keys or j/k, Enter to open, and q to quit. Inside a destination, b or Escape returns home and q exits the application.

On Navigation and Vehicle screens, u toggles metric/imperial presentation.

Radio controls are 1–4 to select FM, scanner, airband, or weather band; p toggles the selected receiver; Left/Right tunes by one mode-specific step; and [/] selects the previous or next preset.

Physical telemetry

Physical navigation sources are selected in runtime TOML with source = "device" for the IMU and GPS inputs. The navigation service owns those devices and continues publishing the same contracts.

Physical automotive/ELM327 composition is not yet enabled in services.automotive; source = "device" currently fails explicitly. Once connected, it will replace the simulated VehicleStateSourceIf without requiring changes to Car TUI.

See services/navigation/README.md, services/automotive/README.md, messaging/README.md, and docs/messaging/message_bus_idd.md for service ownership and wire-contract details.