Hands-On: Complete Architecture Project - System Architecture

Lab: Complete Architecture Project

Deliverable	Specification	Review Criterion
System functional architecture	Function tree: 12+ functions; ASIL tags; interface signals	All ASIL-B+ functions have ISO 26262 Part 3 justification
Physical network topology	Zone topology: HPC + 3 zone ECUs + gateway; 4+ buses	All bus loads < 60%; all ECUs connected
Resource budgets	CPU/ROM/RAM per ECU; bus load per segment	All budgets within limits
Safety architecture	ASIL decomposition for one ASIL-D function; architecture FMEA	Decomposition valid; FMEA complete
ADR package	3+ ADRs for key architecture decisions	Each ADR has context, options, rationale, consequences
Review checklist	Architecture review checklist completed	All mandatory items PASS

Exercise 1: Zone EEA Architecture Summary

Pythoncomplete_architecture.py

"""Complete zone E/E architecture summary report."""

ARCHITECTURE = {
    "name": "Zone Vehicle EEA v2.0",
    "ecus": [
        {"id":"HPC",    "type":"NVIDIA Orin", "asil":"ASIL-B","cpu_mips":254000,"rom_kb":65536,"functions":["Camera_OD","Radar_Fusion","AEB","ACC","LKA","InfoHMI"]},
        {"id":"ZONE_FL","type":"S32K344",     "asil":"ASIL-D","cpu_mips":200,   "rom_kb":4096, "functions":["Window_FL","Door_FL","Mirror_FL","Zone_GW_FL"]},
        {"id":"ZONE_FR","type":"S32K344",     "asil":"ASIL-D","cpu_mips":200,   "rom_kb":4096, "functions":["Window_FR","Door_FR","Camera_Surround","Zone_GW_FR"]},
        {"id":"ZONE_R", "type":"S32K324",     "asil":"ASIL-D","cpu_mips":160,   "rom_kb":2048, "functions":["Rear_Lights","Trunk","Trailer","Zone_GW_R"]},
        {"id":"GATEWAY","type":"S32G3",       "asil":"ASIL-B","cpu_mips":800,   "rom_kb":8192, "functions":["CAN_GW","DoIP","OTA_Mgr","Diag","SOME_IP_SD"]},
        {"id":"EPS",    "type":"TC397",       "asil":"ASIL-D","cpu_mips":500,   "rom_kb":8192, "functions":["EPS_Control"]},
        {"id":"ESC",    "type":"TC397",       "asil":"ASIL-D","cpu_mips":500,   "rom_kb":4096, "functions":["ABS","ESC","AEB_Braking"]},
    ],
    "buses": [
        {"id":"ETH_BB",  "type":"1000BASE-T1", "load_pct": 22, "nodes":["HPC","GATEWAY","TELEMATICS"]},
        {"id":"ETH_FL",  "type":"100BASE-T1",  "load_pct": 18, "nodes":["HPC","ZONE_FL"]},
        {"id":"ETH_FR",  "type":"100BASE-T1",  "load_pct": 31, "nodes":["HPC","ZONE_FR"]},
        {"id":"ETH_R",   "type":"100BASE-T1",  "load_pct": 12, "nodes":["HPC","ZONE_R"]},
        {"id":"CAN_CHAS","type":"CAN-FD 500k", "load_pct": 54, "nodes":["GATEWAY","EPS","ESC","BCM"]},
    ]
}

print("E/E Architecture Summary:")
print(f"  Total ECUs: {len(ARCHITECTURE['ecus'])}")
print(f"  Total buses: {len(ARCHITECTURE['buses'])}")
overloaded = [b for b in ARCHITECTURE["buses"] if b["load_pct"] >= 60]
print(f"  Buses over 60% load: {[b['id'] for b in overloaded] or 'None'}")

Exercise 2: Architecture Review Gate

Pythonarch_review_gate.py

"""Architecture review gate: check all mandatory items."""
from complete_architecture import ARCHITECTURE

failures = []

# Bus load check
for bus in ARCHITECTURE["buses"]:
    if bus["load_pct"] >= 60:
        failures.append(f"Bus {bus['id']} load {bus['load_pct']}% >= 60% limit")

# All functions allocated
all_funcs = [f for e in ARCHITECTURE["ecus"] for f in e["functions"]]
required_funcs = ["AEB","EPS_Control","ESC","Camera_OD","OTA_Mgr"]
for fn in required_funcs:
    if fn not in all_funcs:
        failures.append(f"Required function {fn} not allocated to any ECU")

# ASIL-D ECUs have sufficient max ASIL
for ecu in ARCHITECTURE["ecus"]:
    if any(f in ["EPS_Control","AEB_Braking"] for f in ecu["functions"]):
        if ecu["asil"] not in ["ASIL-D","ASIL-C"]:
            failures.append(f"Safety function on {ecu['id']} ASIL {ecu['asil']} -- insufficient")

if failures:
    print("REVIEW GATE FAILED:")
    for f in failures: print(f"  {f}")
else:
    print("REVIEW GATE PASSED: Architecture ready for Tier-1 design start")

Summary

The complete architecture project lab integrates all course topics into a deliverable that mirrors what a system architect produces at the end of the architecture phase of a real automotive project. The architecture review gate script is the automation of the review checklist: it turns the subjective "does the architecture look right?" judgment into an objective pass/fail result that can run in CI/CD alongside the architecture model changes. The ADR package is the institutional memory that will be consulted for the next 10 years by engineers maintaining and evolving the platform -- investing in clear, honest ADRs with explicit trade-off documentation is one of the highest-leverage architecture activities, even though it produces no ECU firmware and no test cases.

🔬 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.