Integration with Classic ECUs - AUTOSAR Adaptive Platform

Adaptive↔Classic Gateway

When an Adaptive ECU (running Linux/QNX) needs to exchange data with a Classic ECU (running OSEK), a gateway application bridges the two worlds. The gateway may run on the Adaptive SoC itself (if it has a CAN controller) or on a dedicated gateway ECU.

Gateway Architecture

  Adaptive SoC (Linux)                Classic MCU (OSEK)
  ┌─────────────────────────────┐      ┌──────────────────────┐
  │  Adaptive App               │      │  Classic SWC         │
  │  (SOME/IP Event producer)   │      │  (reads COM signal)  │
  └──────────┬──────────────────┘      └─────────┬────────────┘
             │ SOME/IP Event                      │ RTE API
  ┌──────────▼──────────────────┐      ┌──────────▼────────────┐
  │  Gateway Application        │      │  Classic COM          │
  │  (ara::com proxy)           │──────►  (PduRouter → CAN)   │
  │  maps SOME/IP → CAN signal  │ CAN  └───────────────────────┘
  └─────────────────────────────┘

Signal Routing Path

Step	Protocol	Component
Adaptive App calls Send(imuData)	SOME/IP Event (Ethernet)	ara::com skeleton
Gateway App receives via SOME/IP proxy	SOME/IP (Ethernet)	ara::com proxy + SetReceiveHandler
Gateway maps data to Classic COM signal	CAN frame PDU	Classic COM API (Com_SendSignal)
Classic BSW routes PDU to CAN	CAN PDU	PDU Router → CAN Driver
Classic SWC reads signal via RTE	RTE port	Rte_Read_Port_Signal()

Diagnostic Bridging

A DoIP tester on Ethernet connects to the Adaptive ECU's ara::diag server. For Classic ECUs without Ethernet, the Adaptive ECU acts as a DoIP-to-UDS-over-CAN gateway, forwarding requests via the Classic DCM.

C++diag_bridge.cpp

// Forward UDS request from DoIP tester to Classic ECU via CAN
diagServer.RegisterService(0x22, [&](auto req) {
    // Forward to Classic ECU via separate CAN UDS channel
    auto response = classicDiagClient.SendUDSRequest(req);
    return response; // relay Classic ECU's response back to DoIP tester
});

Timing Constraints

Gateway applications introduce latency between the Adaptive event source and the Classic COM signal consumer. This must be accounted for in E2E Deadline Supervision windows and SOME/IP event cycle times.

Path Segment	Typical Latency
SOME/IP event scheduling (UDP)	0.1–1 ms
Gateway application processing	0.5–2 ms
CAN frame transmission (500 kbps, 8-byte frame)	~0.2 ms
Classic BSW COM RX handling	0.1–0.5 ms (next MainFunction call)
Total end-to-end (Adaptive → Classic SWC)	1–5 ms typical

Summary

Adaptive↔Classic integration is the dominant architecture in current production vehicles. The gateway pattern, DoIP diagnostic bridging, and careful timing analysis are the core competencies required for system integration engineers working on mixed-platform ECU networks.

🔬 Deep Dive — Core Concepts Expanded

This section builds on the foundational concepts covered above with additional technical depth, edge cases, and configuration nuances that separate competent engineers from experts. When working on production ECU projects, the details covered here are the ones most commonly responsible for integration delays and late-phase defects.

Key principles to reinforce:

Configuration over coding: In AUTOSAR and automotive middleware environments, correctness is largely determined by ARXML configuration, not application code. A correctly implemented algorithm can produce wrong results due to a single misconfigured parameter.
Traceability as a first-class concern: Every configuration decision should be traceable to a requirement, safety goal, or architecture decision. Undocumented configuration choices are a common source of regression defects when ECUs are updated.
Cross-module dependencies: In tightly integrated automotive software stacks, changing one module's configuration often requires corresponding updates in dependent modules. Always perform a dependency impact analysis before submitting configuration changes.

🏭 How This Topic Appears in Production Projects

Project integration phase: The concepts covered in this lesson are most commonly encountered during ECU integration testing — when multiple software components from different teams are combined for the first time. Issues that were invisible in unit tests frequently surface at this stage.
Supplier/OEM interface: This is a topic that frequently appears in technical discussions between Tier-1 ECU suppliers and OEM system integrators. Engineers who can speak fluently about these details earn credibility and are often brought into critical design review meetings.
Automotive tool ecosystem: Vector CANoe/CANalyzer, dSPACE tools, and ETAS INCA are the standard tools used to validate and measure the correct behaviour of the systems described in this lesson. Familiarity with these tools alongside the conceptual knowledge dramatically accelerates debugging in real projects.

⚠️ Common Mistakes and How to Avoid Them

Assuming default configuration is correct: Automotive software tools ship with default configurations that are designed to compile and link, not to meet project-specific requirements. Every configuration parameter needs to be consciously set. 'It compiled' is not the same as 'it is correctly configured'.
Skipping documentation of configuration rationale: In a 3-year ECU project with team turnover, undocumented configuration choices become tribal knowledge that disappears when engineers leave. Document why a parameter is set to a specific value, not just what it is set to.
Testing only the happy path: Automotive ECUs must behave correctly under fault conditions, voltage variations, and communication errors. Always test the error handling paths as rigorously as the nominal operation. Many production escapes originate in untested error branches.
Version mismatches between teams: In a multi-team project, the BSW team, SWC team, and system integration team may use different versions of the same ARXML file. Version management of all ARXML files in a shared repository is mandatory, not optional.

📊 Industry Note

Engineers who master both the theoretical concepts and the practical toolchain skills covered in this course are among the most sought-after professionals in the automotive software industry. The combination of AUTOSAR standards knowledge, safety engineering understanding, and hands-on configuration experience commands premium salaries at OEMs and Tier-1 suppliers globally.