A comprehensive EtherNet/IP communication adapter for the ESP32-P4 microcontroller, integrating sensor support, Modbus TCP, and web-based configuration.

This project implements a full-featured EtherNet/IP adapter device on the ESP32-P4 platform using the OpENer open-source EtherNet/IP stack. The device serves as a bridge between EtherNet/IP networks and local I/O, sensors, and other industrial automation components.

• EtherNet/IP Adapter: Full OpENer stack implementation with I/O connections

  • Input Assembly 100 (32 bytes)
  • Output Assembly 150 (32 bytes)
  • Configuration Assembly 151 (10 bytes)
  • Support for Exclusive Owner, Input Only, and Listen Only connections

• IMU Integration: 6-axis motion sensor support (MPU6050 primary, LSM6DS3 fallback)

  • MPU6050: Accelerometer-based orientation calculation
  • LSM6DS3: Sensor fusion (complementary filter) combining accelerometer and gyroscope for accurate orientation
  • Roll, pitch, and ground angle from vertical calculation (both sensors)
  • Cylinder pressure calculations for opposed cylinders
  • Data mapped to Input Assembly 100 as 5 DINTs (20 bytes, configurable byte offset)

• Modbus TCP Server: Standard Modbus TCP/IP server (port 502)

  • Input Registers 0-15 map to Input Assembly 100
  • Holding Registers 100-115 map to Output Assembly 150

• Web-Based Configuration Interface: Essential device management

  • Network configuration (DHCP/Static IP)
  • Firmware updates via OTA
  • All other configuration and monitoring available via REST API

• OTA Firmware Updates: Over-the-air firmware update capability

  • File upload via web interface
  • URL-based downloads
  • Automatic rollback on failure

• RFC 5227 Compliant Network Configuration: Address Conflict Detection (ACD)

  • RFC 5227 compliant static IP assignment (implemented in application layer)
  • ACD probe sequence runs before IP assignment (deferred assignment)
  • Natural ACD state machine flow (PROBE_WAIT → PROBING → ANNOUNCE_WAIT → ANNOUNCING → ONGOING)
  • Probe sequence: 3 probes from 0.0.0.0 + 4 announcements (~6-10 seconds total)
  • IP assigned only after ACD confirms no conflict (ACD_IP_OK callback)
  • Callback tracking mechanism prevents false positive conflict detection on timeout
  • Configurable ACD timing parameters (probe intervals, announcement intervals, defensive ARP intervals)
  • Active IP defense with periodic ARP probes from 0.0.0.0 (matching Rockwell PLC behavior)
  • ACD retry logic with configurable delay and max attempts
  • User LED indication (GPIO27): blinks during normal operation, solid on ACD conflict
  • EtherNet/IP Conflict Reporting: Automatic capture and storage of conflict data in TCP/IP Interface Object Attribute #11
  • Custom lwIP modifications for EtherNet/IP requirements

• Microcontroller: ESP32-P4
• Ethernet PHY: IP101 (or compatible)
• I2C Devices: Optional IMU sensor (MPU6050 or LSM6DS3)
• GPIO Configuration:
  • Ethernet: MDC, MDIO, PHY Reset (configurable)
  • I2C: SDA, SCL (configurable, defaults GPIO7/GPIO8)

• ESP-IDF: v5.5.1 or compatible
• Python: 3.x (for build scripts)
• CMake: 3.16 or higher

EIP_GROUND_TRUTH/
├── main/                    # Main application code
├── components/              # Custom components
│   ├── opener/             # OpENer EtherNet/IP stack
│   ├── mpu6050/            # MPU6050 IMU driver
│   ├── lsm6ds3/            # LSM6DS3 IMU driver (fallback)
│   ├── modbus_tcp/         # Modbus TCP server
│   ├── webui/              # Web interface
│   ├── ota_manager/        # OTA update manager
│   ├── system_config/      # System configuration
│   └── log_buffer/         # Log buffer component
├── eds/                     # EtherNet/IP EDS file
├── docs/                    # Documentation
│   ├── ASSEMBLY_DATA_LAYOUT.md  # Byte-by-byte assembly layout
│   ├── API_Endpoints.md         # Web API documentation
│   ├── WIRESHARK_FILTERS.md     # Wireshark filters for debugging
│   └── ExportSniff.md           # Example packet capture analysis
├── dependency_modifications/ # lwIP modifications
├── tools/                   # Testing and debugging tools
│   ├── test_acd_conflict.py     # ACD conflict simulator
│   ├── send_conflict_arp.py      # ARP conflict sender
│   ├── pdml_to_markdown.py      # Wireshark PDML converter
│   └── analyze_arp_timing.py    # ARP timing analyzer
├── scripts/                 # Build scripts
└── FirmwareImages/          # Compiled firmware binaries

1. Install ESP-IDF v5.5.1:

   # Follow ESP-IDF installation guide
   # https://docs.espressif.com/projects/esp-idf/en/latest/esp32p4/get-started/

2. Clone the repository:

   git clone <repository-url>
   cd EIP_GROUND_TRUTH

3. Configure the project:

   idf.py menuconfig

   Key configuration options:

   • Ethernet: PHY address, GPIO pins (MDC, MDIO, Reset)
   • I2C: SDA/SCL GPIO pins, pull-up configuration
   • ACD Timing: RFC 5227 timing parameters

4. Build the firmware:

   idf.py build

5. Flash the firmware:

   idf.py flash

6. Monitor serial output:

   idf.py monitor

The device supports both DHCP and static IP configuration:

• DHCP Mode: Automatic IP assignment via DHCP server
• Static IP Mode: Manual configuration with Address Conflict Detection (ACD)
  • IP address, netmask, gateway
  • Primary and secondary DNS servers
  • Hostname configuration

Configuration can be done via:

• Web interface: http://<device-ip>/
• EtherNet/IP CIP services
• NVS (Non-Volatile Storage)

The device automatically detects and uses MPU6050 if available, otherwise falls back to LSM6DS3. Both sensors provide:

• Roll and Pitch: Orientation angles from horizontal (degrees)
• Ground Angle: Angle from vertical (degrees)
• Cylinder Pressures: Calculated pressures for two opposed cylinders based on orientation, tool weight, tip force, and cylinder bore

Calculation Precision:

• All sensor calculations use 32-bit float precision (IEEE 754 single precision)
• Ground angle calculation: acos(cos(roll) × cos(pitch)) for both MPU6050 and LSM6DS3 (correct 3D angle formula)
• Typical accuracy: ±0.04° for ground angle calculations (sufficient for industrial sensor applications)
• Values are scaled by 10000 for angles and 1000 for pressures when stored in assembly data

The sensor data is mapped to Input Assembly 100 (20 bytes, configurable byte offset):

• DINT 0: Roll angle (degrees × 10000)
• DINT 1: Pitch angle (degrees × 10000)
• DINT 2: Ground angle from vertical (degrees × 10000)
• DINT 3: Bottom cylinder pressure (PSI × 1000)
• DINT 4: Top cylinder pressure (PSI × 1000)

Configuration via web API:

• Enable/disable sensor
• Configure byte offset (0-12) to avoid conflicts with other sensors
• View real-time readings (roll, pitch, ground angle, pressures)
• Calibrate sensor (LSM6DS3 only)

The device exposes three assembly instances:

• Assembly 100 (Input): 32 bytes of input data

  • IMU sensor data (20 bytes: 5 DINTs, configurable byte offset)
    • DINT 0: Roll angle (degrees * 10000)
    • DINT 1: Pitch angle (degrees * 10000)
    • DINT 2: Ground angle from vertical (degrees * 10000)
    • DINT 3: Bottom cylinder pressure (PSI * 1000)
    • DINT 4: Top cylinder pressure (PSI * 1000)
  • Available space for other sensor data (remaining bytes)

• Assembly 150 (Output): 32 bytes of output data

  • Cylinder bore diameter (byte 29, scaled by 100: 0.01-2.55 inches)
  • Tool weight (byte 30, 0-255 lbs)
  • Tip force (byte 31, 0-255 lbs)
  • Control commands and other output data (bytes 0-28)

• Assembly 151 (Configuration): 10 bytes for configuration

Connection types supported:

• Exclusive Owner: Bidirectional I/O connection
• Input Only: Unidirectional input connection
• Listen Only: Unidirectional input connection (multicast)

For detailed byte-by-byte assembly data layout, see docs/ASSEMBLY_DATA_LAYOUT.md.

Access the web interface at http://<device-ip>/ after the device has obtained an IP address.

The web interface provides essential device management capabilities:

• Network Configuration: Set IP address, netmask, gateway, DNS (DHCP/Static IP modes)
• Firmware Updates: Upload firmware updates via web browser (OTA)

Note: All other device configuration, monitoring, and status information is available via the REST API. The web interface is intentionally minimal to keep it lightweight and focused on essential functions.

For detailed API documentation covering sensor configuration, assembly monitoring, Modbus TCP control, system logs, and more, see docs/API_Endpoints.md.

The device provides a Modbus TCP server on port 502:

• Input Registers (0x04 function code):

  • 0-15: Maps to Input Assembly 100 (32 bytes = 16 registers)

• Holding Registers (0x03, 0x06, 0x10 function codes):

  • 100-115: Maps to Output Assembly 150 (32 bytes = 16 registers)
  • 150-154: Maps to Configuration Assembly 151 (10 bytes = 5 registers)

All assembly data is stored in little-endian format (Modbus converts to big-endian for transmission).

For detailed register-to-byte mapping, see docs/ASSEMBLY_DATA_LAYOUT.md.

The EDS (Electronic Data Sheet) file is located at eds/ESP32P4_OPENER.eds. This file can be imported into EtherNet/IP configuration tools to discover and configure the device.

Key device information:

• Vendor: AGSweeney Automation (Vendor Code: 55512)
• Product: ESP32P4-EIP (Product Code: 1)
• Type: General Purpose Discrete I/O

This project includes custom modifications to the lwIP network stack for RFC 5227 compliance and EtherNet/IP optimization. See dependency_modifications/LWIP_MODIFICATIONS.md for details.

• RFC 5227 compliant static IP assignment (implemented in application layer)
• Configurable ACD timing parameters
• Increased socket and connection limits
• IRAM optimization for network performance
• Task affinity configuration

Note: These modifications are required for proper EtherNet/IP operation. They must be reapplied when upgrading ESP-IDF.

Firmware updates can be performed via:

1. Web Interface: Upload binary file directly
2. REST API: POST to /api/ota/update with file or URL
3. EtherNet/IP: Via CIP services (if implemented)

The device supports automatic rollback on failed updates and maintains two OTA partitions for safe updates.

• Serial Logging: Available via UART (default 115200 baud)
• Web Log Buffer: 32KB circular buffer accessible via web interface
• Log Levels: Configurable via menuconfig
• Wireshark Filters: See docs/WIRESHARK_FILTERS.md for ACD debugging filters
• Testing Tools: See tools/README.md for ACD conflict simulators and network analysis tools

This project uses custom components and modified dependencies. When contributing:

1. Follow ESP-IDF coding conventions
2. Document any lwIP modifications clearly
3. Test with real EtherNet/IP controllers
4. Update EDS file if assembly structure changes

This project's own code (main application, Web UI, Modbus TCP, MPU6050 driver, OTA manager, system configuration, etc.) is licensed under the MIT License. See individual source files for copyright attribution.

This project uses the OpENer EtherNet/IP stack, which is licensed under an adapted BSD-style license. The OpENer license file is included in components/opener/LICENSE.txt and must be preserved in all distributions.

All OpENer source files retain their original copyright notices:

• Copyright (c) 2009, Rockwell Automation, Inc.
• Modifications by Adam G. Sweeney agsweeney@gmail.com are clearly marked

This project includes a modified version of lwIP from ESP-IDF v5.5.1. The lwIP modifications are clearly marked with attribution. Original lwIP license terms apply.

Note: EtherNet/IP™ is a trademark of ODVA, Inc.

1. Check Ethernet cable connection
2. Verify PHY address configuration (default: 1)
3. Check serial logs for link status
4. Verify GPIO pin configuration

1. Verify IP address is not in conflict (check ACD status)
2. Check firewall rules (port 44818/TCP and UDP)
3. Verify EDS file is imported correctly
4. Check connection timeout settings

1. Run I2C bus scan via web interface
2. Verify I2C address:
   • MPU6050: 0x68 (default) or 0x69 (if AD0 pin is high)
   • LSM6DS3: 0x6A (default) or 0x6B (if SDO pin is high)
3. Check pull-up resistors (internal vs external, configurable via API)
4. Review serial logs for I2C errors
5. The device will automatically try LSM6DS3 if MPU6050 is not detected

1. Verify partition table has OTA partitions
2. Check available flash space
3. Verify firmware binary is for correct ESP32-P4 variant
4. Check serial logs for OTA error messages

• OpENer Documentation
• ESP-IDF Programming Guide
• EtherNet/IP Specification
• Modbus TCP/IP Specification
• RFC 5227 - IPv4 Address Conflict Detection
• MPU6050 Datasheet
• LSM6DS3 Datasheet

• ACD and EtherNet/IP Conflict Reporting - Complete guide to ACD conflict detection and EtherNet/IP integration
• Assembly Data Layout - Byte-by-byte assembly data documentation
• API Endpoints - Web UI REST API documentation
• Wireshark Filters - Network debugging filters for ACD

For issues and questions:

• Check the documentation in docs/
• Review serial logs for error messages
• Consult OpENer and ESP-IDF documentation

Device Name: ESP32P4-EIP
Vendor: AG Sweeney

Firmware Version: See git commit or build timestamp