Story
Product Overview
The IOL HAT is an industrial-grade Hardware Attached on Top (HAT) module that transforms a standard Raspberry Pi into a IO-Link master controller. It enables seamless integration of industrial sensors, actuators, and other devices compliant with IEC 61131-9 (IO-Link, also known as SDCI) into embedded applications and Industrial IoT systems.
Hardware Architecture
Core
- Dimensions: 65.5 × 66 mm footprint, 18 mm height with stack-through capability
- Mounting: 4×2.5 mm screwholes compatible with standard Raspberry Pi mounting points (standoffs included)
- Primary Supply: 24V DC (±20% tolerance) via 3.5mm screw-plug connector
SDCI (IO-Link) Port Configuration
- Ports: 2 independent SDCI ports per HAT module
- Connector Type: 3.5mm 2-pin screw-plug terminals
- Compliance: Class A IO-Link specification (≤500mA per port)
- Communication Speeds: Auto-detection supporting COM1, COM2, COM3 modes
- Operating Mode: IOL1 standard with dedicated status LEDs (red/green per port)
Raspberry Pi Interface
- Primary Connection: 40-pin GPIO stack-through connector
Software Architecture
Master Application Stack
The IOL HAT utilizes an open source software (available on IOL HAT - GitHub) built on the industry-proven I-Link stack from RT-Labs, providing:
- IO-Link Master Stack: Full IEC 61131-9 compliant master implementation
- User application interface: TCP socket-based binary protocol, commands:
- Port power control (on/off)
- Process data read/write operations
- Parameter data access (read/write)
- Port information retrieval
- LED status control
Programming Language Support
The TCP socket interface enables development in multiple programming languages:
- Python (examples provided)
- C/C++ (examples provided)
- Node-RED (via IOL Connect Manager software, additional functions)
- Any language supporting TCP socket communication
Advanced Features
IOL Connect Manager Add-on (additional license required)
Professional-grade software enhancement providing:
- IODD File Handling: Automatic device description processing
- Node-RED Integration: Visual programming interface for rapid prototyping
- JSON API: RESTful interface for web-based applications
- Web Interface: Browser-based configuration, testing, and parametrization
- Database Integration: SQLite database for data logging and management
- Smart Gateway Capabilities: Complete IoT gateway solution
Scalability Architecture
- Single HAT: Up to 2 SDCI devices
- Stacked Configuration: Up to 2 IOL HATs per Raspberry Pi (40-pin GPIO stacking)
- Maximum Capacity: 4 SDCI devices per Raspberry Pi system
Compatibility Matrix
Raspberry Pi Models
| Model | RAM | OS | Tested Speed | Status |
|---|---|---|---|---|
| Raspberry Pi 3B | 1GB | Raspberry OS 12 (Bookworm) | COM2 | Verified |
| Raspberry Pi 4B | 1GB+ | Raspberry OS 12 (Bookworm) | COM3 | Verified |
| Raspberry Pi 5 | 4GB+ | Raspberry OS 12 (Bookworm) | COM3 | Verified |
Device Compatibility
- Standard Compliance: SDCI devices according to IEC 61131-9 (IO-Link)
- Device Universe: Over 20,000 different sensor and actuator types
- Manufacturer Independence: Any IO-Link compatible device regardless of vendor
- Power Classification: Class A devices (≤500mA power consumption)
- Standard M12 interface: Adapter cables available
Integration Efficiency
- Setup Time: Rapid deployment with pre-compiled master application and
- User examples: user application examples for Python and C/C++ available
- Add-on software: IOL Connect Manager with web-interface, Node-RED integration and JSON-API
