# Hardware RNG Implementation Status

## Overview

The OTP cipher application now includes comprehensive hardware Random Number Generator (RNG) device support with automatic detection, device identification, and graceful handling of different device types.

## Supported Devices

### ✅ Fully Supported (TrueRNG Family)
- **TrueRNG Original** (VID: 04d8, PID: f5fe)
- **TrueRNG Pro** (VID: 04d8, PID: 0aa0)  
- **TrueRNG Pro V2** (VID: 04d8, PID: ebb5)

These devices work via serial port communication and are fully integrated into the entropy collection system.

### ⚠️ Detected but Not Supported (SwiftRNG Family)
- **SwiftRNG** (VID: 1fc9, PID: 8111)

SwiftRNG devices are detected and identified but cannot be used via serial port communication. They require the official SwiftRNG API with libusb-1.0 integration.

## Implementation Features

### Device Detection
- **Automatic scanning** of `/dev/ttyUSB*` and `/dev/ttyACM*` devices
- **VID/PID identification** via sysfs to distinguish device types
- **Multi-device support** with interactive selection menus
- **Real-time status indicators** showing device availability

### Device Communication
- **Optimized serial port configuration** for each device type
- **Timeout protection** to prevent hanging on unresponsive devices
- **Error handling** with clear diagnostic messages
- **Progress tracking** with speed estimation for large entropy collections

### Integration Points
- **Pad enhancement** via entropy addition to existing pads
- **Interactive menus** for device selection when multiple devices are present
- **Command-line support** for automated workflows
- **Graceful fallback** to other entropy sources when no hardware RNG is available

## Technical Implementation

### Core Functions
- `detect_all_hardware_rng_devices()` - Scans and identifies all connected devices
- `collect_truerng_entropy_from_device()` - Collects entropy from TrueRNG devices