Delphi-OBD

Comprehensive Delphi library for OBD-II diagnostics, vehicle protocols, and automotive utilities.

Repository Structure

The repository is organized into logical folders for better maintainability:

├── src/                    # Source code organized by functionality
│   ├── Adapters/          # OBD adapter implementations (ELM327, OBDLink, AT/ST commands)
│   ├── Components/        # Visual components (gauges, displays, LEDs, headers)
│   ├── Connection/        # Connection types (Serial, Bluetooth, WiFi, FTDI, UDP)
│   ├── CustomControls/    # Custom control framework and animations
│   ├── Forms/             # Form templates and base classes
│   ├── Protocol/          # Vehicle protocols (CAN, DoIP, J1939, Legacy)
│   ├── RadioCode/         # Radio code calculators (32+ brands)
│   ├── Services/          # OBD services 01-0A (SAE J1979 compliant)
│   ├── Utilities/         # Logger, string helpers, settings, data modules
│   ├── VIN/               # VIN decoder and utilities
│   └── Wizards/           # IDE wizards for project creation
├── docs/                   # Documentation (see docs/index.md)
│   ├── README.md          # Main documentation
│   ├── ARCHITECTURE.md    # Module map and rendering pipeline
│   ├── PROTOCOLS.md       # Wire-level protocol reference (CAN, DoIP, J1939, Legacy)
│   ├── COMPONENT_AUTHORING.md # How to add a new visual component
│   ├── CATALOG_FORMAT.md  # OEM catalog JSON schema (v2)
│   ├── RADIO_CALCULATORS.md  # Radio code calculator guide
│   ├── ROADMAP.md         # Releases shipped + future backlog
│   └── TROUBLESHOOTING.md # Common installation and runtime issues
├── examples/               # Example applications
│   ├── minimal/           # Minimal OBD connection example
│   ├── simple/            # Simple diagnostic example
│   ├── advanced/          # Advanced features demo
│   ├── serial/            # Serial connection example
│   ├── bluetooth/         # Bluetooth connection example
│   ├── wifi/              # WiFi connection example
│   ├── ftdi/              # FTDI connection example
│   └── doip/              # DoIP protocol example
├── Packages/               # Delphi package files
└── Resources/              # Images, icons, and other resources

Quick Start

Installation

1. Install Skia4Delphi: First, install Skia4Delphi from GetIt Package Manager (required dependency)
2. Add to Library Path: Add the src folder and its subfolders to your Delphi library path
3. Install Packages:
   • First, compile and install Packages\RunTime.dpk
   • Then, compile and install Packages\DesignTime.dpk
   • The packages are configured to output to the standard Delphi BPL directory ($(BDSCOMMONDIR)\Bpl)
4. Start using the components and classes in your project

Note: The packages require Skia4Delphi to be installed first. The package output directory is set to the standard Delphi BPL folder, ensuring that the Skia DLL is accessible when loading the packages.

Basic Usage

uses
  OBD.Connection,
  OBD.Adapter,
  OBD.Service01;

var
  Connection: TOBDConnection;
  Adapter: TOBDAdapter;
  Service01: TOBDService01;
begin
  // Create connection
  Connection := TOBDConnectionSerial.Create;
  Connection.Connect('COM3', 38400);
  
  // Create adapter
  Adapter := TOBDELM327.Create(Connection);
  
  // Use Service 01
  Service01 := TOBDService01.Create;
  // Request engine RPM, temperature, etc.
end;

See the examples folder for complete working examples.

Features

OBD-II Services (SAE J1979)

• Service 01: Live data (PIDs 00-FF)
• Service 02: Freeze frame data
• Service 03: Stored diagnostic trouble codes
• Service 04: Clear DTCs and MIL
• Service 05: Oxygen sensor test results
• Service 06: On-board monitoring test results
• Service 07: Pending trouble codes
• Service 08: Control of on-board systems
• Service 09: Vehicle information
• Service 0A: Permanent trouble codes

Protocols

• CAN (ISO 15765-4)
• DoIP (ISO 13400) — Windows (WinSock), cross-platform (System.Net.Socket), and TLS-secured (ISO 13400-3 §7) variants
• UDS (ISO 14229) with async client (OBD.OEM.UdsClient.Async) — future-returning facade with cooperative cancellation
• J1939 (SAE J1939 for heavy-duty vehicles)
• Legacy (ISO 9141-2, ISO 14230 KWP2000)

Adapters

• ELM327 (complete AT command set)
• OBDLink (ST command support: SX, MX, EX models)
• Voltage monitoring
• Connection retry with exponential backoff
• Capture/replay transport (.obdlog round-trip) for deterministic testing

OEM Coverage

• 79 OEM catalogs / 247,279 entries / 5 vehicle classes (passenger, motorcycles, agricultural, marine, powersports)
• JSON Schema v2 (catalogs/_schema/oem-catalog-v2.json) with DTC formats for SAE J2012, J1939 SPN-FMI, and 22 OEM prefixes
• See docs/CATALOG_FORMAT.md and catalogs/INDEX.md

Radio Code Calculators

32+ brand-specific radio code calculators:

• Japanese: Nissan, Toyota, Honda, Mazda, Mitsubishi, Subaru, Suzuki, Hyundai/Kia
• European: Mercedes, BMW, Opel, Volvo, VW, Audi, SEAT, Skoda, Renault, Peugeot, Citroen, Fiat
• American: Ford, Chrysler/Jeep/Dodge, GM (Chevrolet, Cadillac, GMC, Buick)
• Universal: Becker, Blaupunkt, Alpine, Clarion, Visteon

See docs/RADIO_CALCULATORS.md for details.

Visual Components

• Circular gauges with animations
• Matrix displays
• LED indicators
• Touch-friendly headers and status bars
• Customizable styling with Skia rendering

Connection Types

• Serial (RS-232)
• Bluetooth
• WiFi/UDP
• FTDI USB
• DoIP over Ethernet

Utilities

• Production-ready logger (with rotation, severity levels, thread-safe)
• String optimization helpers
• VIN decoder (manufacturer, model year, check digit validation)
• Application settings management

Documentation

• Documentation Index - Map of every doc by topic
• Architecture - Module map and rendering pipeline
• Protocols - Wire-level protocol reference
• Component Authoring - How to add a new visual component
• Catalog Format - OEM catalog JSON schema
• Radio Calculators - Radio code algorithms and usage
• Roadmap - Releases shipped + future backlog
• Troubleshooting - Common installation and runtime issues

Examples

Browse the examples folder for working demonstrations:

• minimal - Bare minimum connection setup
• simple - Basic diagnostic operations
• advanced - Advanced features and protocols
• serial/bluetooth/wifi/ftdi - Connection-specific examples
• doip - Diagnostic over IP example

Requirements

• Embarcadero Delphi 11 or higher
• VCL components: Windows 7, 8/8.1, 10, 11
• FMX components and cross-platform DoIP: Windows, macOS, Linux, iOS, Android
• Skia4Delphi (for visual components)
• OpenSSL + Indy 10 (for DoIP TLS only)

License

Open source under Apache 2.0 License

Author

Ernst Reidinga (ERDesigns)

Contributing

Contributions are welcome! See CONTRIBUTING.md and docs/ROADMAP.md for current development priorities.

Support

For issues, questions, or contributions, please visit the GitHub repository.