v1.3.0 - ESP32-C6 Platform Support

[francescopace]

Complete multi-platform support with ESP32-C6 and WiFi 6

Added comprehensive support for ESP32-C6 alongside ESP32-S3, enabling WiFi 6 (802.11ax):

ESP32-C6 Implementation:

• CSI Configuration: Implemented wifi_csi_acquire_config_t structure

  • .acquire_csi_legacy = 1 - Captures CSI from 802.11a/g packets (L-LTF)
  • .acquire_csi_ht20 = 1 - Captures CSI from 802.11n HT20 packets (64 subcarriers)
  • .acquire_csi_ht40 = 0 - Captures CSI from 802.11n HT40 packets (128 subcarriers) - to be tested
  • .acquire_csi_su = 1 - Captures CSI from WiFi 6 Single-User packets
  • Critical: Both acquire_csi_legacy and acquire_csi_ht20 required for callback invocation

• WiFi 6 Support: Enabled 802.11ax protocol for ESP32-C6

  • Automatic negotiation with WiFi 6 routers
  • Backward compatible with WiFi 4/5 routers
  • Improved packet scheduling and efficiency

Configuration Files:

• sdkconfig.defaults.esp32c6: ESP32-C6 specific configuration
  • DIO flash mode (more stable than QIO)
  • USB stability improvements (PM disabled)
  • Simplified CSI API configuration

Critical Fix - CSI Callback Issue:

• Root cause: Incomplete CSI configuration (only .enable = 1 was insufficient)
• Solution: Added all required acquire_csi_* fields
• Result: CSI callback now working, 50-100+ packets/second

Testing Infrastructure:

• Added real_csi_data_esp32_c6.h: 2015 lines of real CSI test data
• Renamed real_csi_data.h → real_csi_data_eps32_s3.h for clarity
• Added segmentation_analysis_c6.png: Visual analysis of C6 performance
• Rewrote test_segmentation_local.py: Complete rewrite for better parameter analysis
  • Grid search optimization
  • Visual segmentation analysis
  • Platform-specific parameter validation

Documentation:

• Removed ESP32-S3 specific references from user-facing documentation
• Updated platform badges and hardware requirements
• Added platform comparison tables
• Clarified platform-specific features and limitations
• Updated ESP32-PLATFORM-SUPPORT.md with platform-specific defaults

Reference: ESP-IDF Issue #14271 - espressif/esp-idf#14271

🔧 Runtime-Configurable Parameters

Major system configurability improvements

Transformed hardcoded parameters into runtime-configurable settings, enabling fine-tuning without recompilation:

Segmentation Parameters (MQTT-configurable):

• Threshold: Direct value setting (0.5-10.0)
• K factor: Threshold sensitivity multiplier (0.5-5.0)
  • Higher values = less sensitive (fewer false positives)
  • Lower values = more sensitive (better detection of subtle movements)
• Window size: Moving variance window (3-50 packets)
  • Smaller = more reactive, larger = more stable
• Min segment length: Minimum motion duration (5-100 packets)
• Max segment length: Maximum motion duration (10-200 packets)
• Platform-specific defaults: Optimized separately for ESP32-S3 and ESP32-C6

Subcarrier Selection (runtime-configurable):

• Dynamic subcarrier selection for feature extraction
• New API: csi_set_subcarrier_selection()
• Configurable via MQTT with array of indices (0-63)
• Allows optimization for different environments and interference patterns

New MQTT Commands:

• segmentation_threshold <value> - Set detection threshold
• segmentation_k_factor <value> - Set threshold sensitivity
• segmentation_window_size <value> - Set moving variance window
• segmentation_min_length <value> - Set minimum segment length
• segmentation_max_length <value> - Set maximum segment length

Enhanced Stats Command:

• Now displays all configurable parameters
• Shows current subcarrier selection
• Provides real-time configuration overview

Benefits:

• ✅ No recompilation needed for parameter tuning
• ✅ Easy optimization for different environments
• ✅ Platform-specific defaults (ESP32-S3 vs ESP32-C6)
• ✅ All parameters saved to NVS automatically
• ✅ Simplified testing and validation workflow

✨ Added - System Resource Monitoring

Real-time CPU and RAM usage in stats command

• Added cpu_usage_percent and heap_usage_percent fields to stats command response
• Calculated using FreeRTOS runtime statistics and ESP-IDF heap APIs
• Minimal overhead (< 0.1% CPU, ~150 bytes RAM)
• Requires FreeRTOS runtime stats enabled in sdkconfig (added to all platform configs)
• Web UI updated to display CPU and RAM in statistics modal

Real-world performance (ESP32-C6 with all filters + features):

• CPU: 5.4%, Heap: 22.3% - confirms excellent resource efficiency

🌐 Web-Based Real-Time Monitor

Modern web interface for ESPectre monitoring and configuration

New espectre-monitor.html provides a comprehensive web-based alternative to the CLI shell:

Features:

• Real-time visualization: Live chart of movement and threshold values
• Interactive metrics: State, movement, threshold, and segment counters
• Complete configuration: All detection parameters and filters controllable via web UI
  • Segmentation threshold (0.5-10.0)
  • Traffic generator rate (0-50 pps)
  • Features extraction toggle
  • Smart publishing toggle
  • All filters (Hampel, Savitzky-Golay, Butterworth, Wavelet) with parameters
• Device information: Displays ESP32 IP address
• Statistics viewer: Runtime statistics in modal popup
• Auto-sync: Automatically loads current configuration on connection
• Factory reset: Web-based factory reset with confirmation

Technical details:

• Single HTML file (no dependencies except CDN libraries)
• MQTT.js for WebSocket communication
• Chart.js for real-time data visualization
• Responsive design with collapsible sections
• Toast notifications for command feedback

Benefits:

• ✅ No terminal required - works in any modern browser
• ✅ Visual feedback and easier parameter tuning
• ✅ Multi-device support (can monitor multiple ESPectre nodes)
• ✅ Cross-platform (works on desktop, tablet, mobile)
• ✅ Can replace espectre-cli.sh for most use cases

🔧 MQTT Data Structure Optimization

Simplified and standardized MQTT message format

Optimized MQTT data structure for consistency and reduced bandwidth:

Periodic Data (published during detection):

• ❌ Removed segments_total (not needed for motion detection)
• ✅ Kept essential fields: movement, threshold, state, features (optional), timestamp

Stats Command Response:

• ❌ Removed entire segments object (total, active, last_completed)
• ✅ Renamed moving_variance → movement (consistent with periodic data)
• ✅ Renamed adaptive_threshold → threshold (consistent with periodic data)
• ✅ Kept turbulence for diagnostics
• ✅ Simplified to essential runtime metrics only

Code Cleanup:

• ❌ Removed segment_t structure from segmentation.h
• ❌ Removed segment array and tracking logic from segmentation.c (~150 lines)
• ❌ Removed functions: segmentation_get_num_segments(), segmentation_get_segment(), segmentation_clear_segments(), segmentation_get_active_segments_count(), segmentation_get_last_completed_segment()
• ✅ Simplified state machine to focus only on IDLE ↔ MOTION transitions

MQTT Handler Simplification:

• Removed mqtt_publish_calibration_status() function
• Removed mqtt_publish_calibration_complete() function
• Added mqtt_publish_binary() for CSI raw data collection
• Simplified API focused on segmentation-only approach

Benefits:

• 📉 Reduced message size and memory usage
• 🔄 Consistent field naming between periodic data and stats
• 🎯 Cleaner API focused on motion detection
• 🧹 Simpler codebase (~200 lines removed)
• 🐛 Fixed bug where last_completed_segment showed stale data after 10 segments

🛠️ Enhanced Tools

Web Monitor:

• Added controls for all new segmentation parameters
• Real-time parameter adjustment with visual feedback
• Improved configuration synchronization

CLI (espectre-cli.sh):

• Added commands for segmentation parameter configuration
• Improved interactive menu with new options
• Better parameter validation and feedback

📚 Documentation & Cleanup

Documentation Updates:

• CALIBRATION.md: Added runtime parameter configuration section
• SETUP.md: Updated with new MQTT commands and examples
• ESP32-PLATFORM-SUPPORT.md: Clarified platform-specific defaults

Code Cleanup:

• Removed .DS_Store file
• Updated .gitignore with better patterns
• Removed obsolete convert_csi_to_header.py script

---

This discussion was created from the release v1.3.0 - ESP32-C6 Platform Support.