Function Adapter#

Overview and Purpose#

The Function Adapter is a critical abstraction layer that bridges vehicle functions with underlying middleware platforms. It serves as a standardized wrapper that enables vehicle functions to be integrated and executed on any middleware without modification.

Key Purposes of the Function Adapter:

  1. Middleware Abstraction: The Function Adapter decouples the vehicle function implementation from the specific middleware platform, allowing the same function logic to run on different runtimes and integration targets.

  2. Static API Contract: It implements the stable, agreed-upon static API contract derived from the meta model. This contract ensures consistent interface definitions, data types, scheduling behavior, and safety semantics across different implementations.

  3. Safety and Integrity: The Function Adapter manages safety-critical aspects including:

  4. Portability: By using the Function Adapter pattern, vehicle functions become portable artifacts that can be:

  5. Not a Full AUTOSAR Application: The Function Adapter is not intended to be a complete replacement for an AUTOSAR Application. It focuses on portable function logic and signal access, while platform-specific capabilities such as middleware integration, lifecycle management, diagnostics, persistence, security, and deployment remain the responsibility of the surrounding runtime environment.

The Function Adapter essentially transforms the abstract specifications defined in the meta model and YAML instances into concrete, executable implementations that maintain the agreed contract regardless of the underlying middleware platform.

signal protection within the stack

Thoughts About Signal Protection#

As shown in the following figure, E2E protection is handled by the middleware layer. Since communication between the application and the middleware is local and considered less critical, a lightweight supervision mechanism based on a complementary signal is used instead of full E2E protection in order to reduce performance impact.

signal protection within the stack

E2E Protection Layer Explained#

The following figures explain why the full E2E Protection is not part of the API.

example of a vehicle network
Table 13 Random / Typical Modules shown in the picture above:#

Abbreviation

Meaning

Function

ECM

Engine Control Module

Controls engine operation, fuel injection, ignition

BCM

Body Control Module

Controls doors, windows, lighting, central locking

ESP / ESC

Electronic Stability Program / Control

Vehicle stability control

ECU

Electronic Control Unit

Generic term for a vehicle controller

TCM

Transmission Control Module

Controls gearbox and gear shifts

TCU

Telematics Control Unit

Connectivity, eCall, OTA updates

ABS

Anti-lock Braking System

Prevents wheel lock during braking

The following figure shows an example of an E2E protection layer and its typical integrity checks.

E2E example