Implemented Ethernet communication on STM32 using lwIP; analyzed real network traffic with Wireshark to validate ARP, ICMP, IPv4, and UDP behavior, and built a UDP-based application protocol to investigate packet loss, buffering limits, and embedded transport tradeoffs. This repository contains selected engineering reference notes covering Ethernet behavior across embedded and automotive systems.
The material is maintained as an engineering notebook, not as a tutorial, textbook, or protocol specification.
Its purpose is to preserve working understanding – the physical behavior, invariants, failure modes, and architectural patterns required to reason correctly about Ethernet-based systems, particularly where the PHY layer, bring-up sequencing, and system integration dominate complexity.
This repository is intended to grow as a long-term Ethernet knowledge base, spanning both conventional and automotive environments.
Topics include, but are not limited to:
- Ethernet framing and encapsulation behavior
- MAC-PHY separation and responsibilities
- PHY-layer behavior and constraints
- embedded Ethernet bring-up principles
- automotive Ethernet PHY fundamentals (e.g. single-pair Ethernet)
- link initialization and training concepts
- debugging methodology and failure interpretation
- Ethernet used as a system communication transport
- interaction with other in-vehicle networks (e.g. CAN)
Concrete examples within the repository are drawn from real hardware bring-up and system experiments, but the underlying principles are not limited to any single microcontroller, PHY, or vendor.
- An engineering reference for Ethernet systems
- A record of system-level reasoning and failure analysis
- A place to consolidate mental models that are difficult to reconstruct from specifications alone
- Focused on understanding why systems behave the way they do
The repository currently organizes material into a small number of focused engineering documents, each serving a distinct purpose:
-
ethernet-foundations.md
Physical and logical behavior of Ethernet on a local area network -
stm32-ethernet-bringup.md
Practical bring-up rules and failure modes observed during embedded Ethernet integration -
ethernet-debugging-and-tools.md
Interpretation of packet captures, filtering behavior, and debugging tools -
ethernet-as-a-transport.md
System-level use of Ethernet as a communication transport within embedded architectures
Additional documents may be added as the scope expands, particularly in areas related to automotive Ethernet PHY behavior and system startup sequencing.
Author: Percival Segui
Independent engineering project record
This repository contains original reference material intended for educational and personal engineering use.