--- title: "StratoTrack LoRa Pro" canonical: https://hamzadenizyilmaz.com.tr/projeler/stratotrack-lora-pro author: "Hamza Deniz Y\u0131lmaz" created: 2026-07-23T02:34:58.0487293+00:00 published: 2026-07-23T02:34:58.0487293+00:00 --- # StratoTrack LoRa Pro ## StratoTrack LoRa Pro **Offline long-range GPS beacon tracker powered by ESP32-C6, NEO-6M GNSS, RAK3172/RAK3272S LoRa P2P, a 2.8-inch SPI TFT dashboard, and a local Wi-Fi web panel.** StratoTrack LoRa Pro is an embedded tracking project designed for offline field use. The tracker reads GPS/GNSS data from a NEO-6M module, renders a professional live dashboard on an ILI9341 TFT screen, broadcasts compact position packets over LoRa P2P using a RAK3172/RAK3272S module, and exposes a local web dashboard from the ESP32-C6 itself. The project does **not** require GSM, SIM cards, cloud services, routers, internet access, or LoRaWAN gateways. It is designed as a direct, offline, long-range LoRa beacon system. --- ## Table of Contents - [Project Goals](#project-goals) - [What This Project Does](#what-this-project-does) - [System Architecture](#system-architecture) - [Hardware Overview](#hardware-overview) - [Main Tracker Hardware](#main-tracker-hardware) - [Second LoRa Receiver Hardware](#second-lora-receiver-hardware) - [Pinout](#pinout) - [Firmware Structure](#firmware-structure) - [Programming Language and Libraries](#programming-language-and-libraries) - [PlatformIO Setup](#platformio-setup) - [Build, Upload and Monitor](#build-upload-and-monitor) - [TFT Dashboard](#tft-dashboard) - [Web Panel](#web-panel) - [GNSS / Satellite Data](#gnss--satellite-data) - [LoRa P2P Protocol](#lora-p2p-protocol) - [Second LoRa Receiver](#second-lora-receiver) - [Packet Format](#packet-format) - [Configuration](#configuration) - [Field Testing Guide](#field-testing-guide) - [Troubleshooting](#troubleshooting) - [Safety and Legal Notes](#safety-and-legal-notes) - [Roadmap](#roadmap) - [License](#license) --- ## Project Goals StratoTrack LoRa Pro was built with the following goals: 1. **Offline operation** The device must work without cellular network, internet, cloud platform, or LoRaWAN gateway. 2. **Long-range beaconing** The tracker periodically transmits compact GPS packets over raw LoRa P2P. 3. **Professional field UI** The device has a local TFT interface showing GPS, satellite, LoRa and TX status. 4. **Local diagnostics** A Wi-Fi access point and local web panel allow live monitoring from a phone or laptop. 5. **Modular firmware** The codebase is organized as multiple firmware modules instead of a single sketch. 6. **Expandable architecture** The project can later support ACK messages, LoRa command mode, multiple nodes, track logging, and additional dashboard pages. --- ## What This Project Does The main tracker device: - reads NMEA data from a NEO-6M GPS module, - determines whether GPS state is ` WAIT `, ` DATA `, or ` FIX `, - parses GPS satellite data from NMEA GSV messages, - displays GPS and LoRa data on a 2.8-inch SPI TFT, - starts a local Wi-Fi access point, - serves a browser-based web dashboard at ` http://192.168.4.1 `, - builds a compact tracker packet, - converts the packet to HEX for RAK RUI3 P2P transmission, - sends the packet over LoRa P2P, - prints detailed debug logs through Serial Monitor. A second LoRa receiver can be added using another ESP32/Arduino-compatible board plus a RAK3172/RAK3272S module. The receiver listens for LoRa P2P packets and decodes the tracker data. --- ## System Architecture ### Main Tracker ```text NEO-6M GPS | | UART / NMEA 9600 baud v ESP32-C6 | | SPI v 2.8-inch ILI9341 TFT Display ESP32-C6 | | UART / RAK RUI3 AT Commands v RAK3172 / RAK3272S LoRa Module | | LoRa P2P 868 MHz v Second LoRa Receiver ``` ### Local Web Panel ```text Phone / Laptop | | Wi-Fi AP v ESP32-C6 Local Web Server | v http://192.168.4.1 ``` The web panel is served directly by the ESP32-C6. No router or internet connection is required. --- ## Hardware Overview ### Main Tracker Hardware Recommended hardware: | Part | Purpose | | --- | --- | | ESP32-C6 DevKitC-1 | Main controller | | NEO-6M GPS | GNSS position source | | RAK3172 / RAK3272S | LoRa P2P modem | | 2.8-inch SPI TFT ILI9341 | Local dashboard | | 18650 / LiPo battery system | Portable power | | USB cable | Programming/debug | | LoRa antenna | Required before TX | ### Second LoRa Receiver Hardware For the second LoRa receiver: | Part | Purpose | | --- | --- | | ESP32 / ESP32-C6 / Arduino-compatible MCU | Receiver controller | | RAK3172 / RAK3272S | LoRa P2P receiver | | USB cable | Serial Monitor | | LoRa antenna | Required | The second receiver firmware listens in P2P mode and prints decoded packets. --- ## Pinout The current tested tracker pinout is: ### Main Tracker: ESP32-C6 + RAK + GPS + TFT | Module | Module Pin | ESP32-C6 Pin | Notes | | --- | --- | --- | --- | | RAK3272S / RAK3172 | UART2\_TX | GPIO0 | ESP32 RX for LoRa | | RAK3272S / RAK3172 | UART2\_RX | GPIO1 | ESP32 TX for LoRa | | RAK3272S / RAK3172 | 3V3 | 3V3 | Do not use 5V | | RAK3272S / RAK3172 | GND | GND | Common ground | | NEO-6M | TX | GPIO4 | GPS TX to ESP32 RX | | NEO-6M | RX | GPIO5 / not required | Optional | | NEO-6M | VCC | 5V or 3V3 depending on board | Most breakout boards work well with 5V | | NEO-6M | GND | GND | Common ground | | TFT ILI9341 | SCK | GPIO6 | SPI clock | | TFT ILI9341 | MOSI | GPIO7 | SPI MOSI | | TFT ILI9341 | MISO | Not connected | Not required | | TFT ILI9341 | CS | GPIO10 | Chip select | | TFT ILI9341 | DC | GPIO2 | Data/command | | TFT ILI9341 | RST | GPIO3 | Reset | | TFT ILI9341 | BL/LED | 3V3 | Backlight always on | ### Important Wiring Rules - All grounds must be common. - RAK LoRa module must be powered from 3.3V. - Do not transmit LoRa without antenna. - GPS RX is optional; only GPS TX is needed for receiving NMEA. - If LoRa returns unreadable characters, check baud rate and TX/RX direction. - If GPS ` NMEA ` count is zero, the GPS TX pin is not reaching ESP32 RX. --- ## Firmware Structure StratoTrack LoRa Pro firmware is written in **C++** using the **Arduino framework** on top of **PlatformIO**. The project is intentionally organized as a modular embedded firmware instead of a single-file sketch. Each hardware responsibility is separated into its own module to make the codebase easier to maintain, debug, extend, and publish as an open-source project. The firmware runs on an **ESP32-C6** main controller and communicates with external modules through UART and SPI interfaces. The GPS module provides GNSS/NMEA data, the RAK LoRa module handles long-range P2P communication through AT commands, the TFT display renders the local dashboard, and the ESP32-C6 exposes a local Wi-Fi web panel. ### ` config.h ` Contains all hardware pin definitions, baud rates, LoRa parameters, display settings, firmware metadata and feature flags. This is the first file to edit when changing: - pins, - LoRa frequency, - spreading factor, - device ID, - Wi-Fi SSID/password, - display rotation, - beacon interval. ### ` globals.h ` / ` globals.cpp ` Contains shared global objects and shared state variables used across modules. Examples: ```cpp TinyGPSPlus gps; HardwareSerial GPSSerial; HardwareSerial LoRaSerial; String gpsState; String loraState; String txState; ``` This prevents duplicate object definitions across multiple ` .cpp ` files. ### ` gps_tracker.h ` / ` gps_tracker.cpp ` Responsible for GPS and GNSS logic: - reads NMEA data from GPS UART, - updates TinyGPSPlus, - tracks NMEA character count, - detects GPS state: ` WAIT `, ` DATA `, ` FIX `, - parses GSV satellite messages, - stores PRN, SNR, elevation and azimuth, - provides helper functions for latitude, longitude, speed, altitude and satellite count. ### ` lora_modem.h ` / ` lora_modem.cpp ` Responsible for RAK3172/RAK3272S communication: - sends AT commands, - configures RAK P2P mode, - builds LoRa tracker packets, - converts packets to HEX, - transmits packets with ` AT+PSEND `, - tracks TX state and last RAK response. ### ` display_ui.h ` / ` display_ui.cpp ` Responsible for the TFT dashboard: - initializes ILI9341, - draws the GNSS panel, - draws LoRa Radio panel, - draws NMEA Stream panel, - shows satellite PRN:SNR values, - shows GPS state, fix, speed and altitude, - shows LoRa and TX state. ### ` web_panel.h ` / ` web_panel.cpp ` Responsible for the local web dashboard: - starts ESP32-C6 Wi-Fi AP, - serves the HTML dashboard, - exposes ` /api/status `, - shows live GPS/LoRa data, - shows satellites, - provides map link when GPS fix is available. ### ` main.cpp ` The firmware entry point: - initializes Serial Monitor, - initializes TFT, - initializes GPS UART, - initializes LoRa UART, - starts web panel, - starts LoRa P2P mode, - runs the main loop, - updates display, - handles web requests, - sends LoRa packets periodically. --- ## Programming Language and Libraries ### Language ```text C++ / Arduino Framework ``` The project uses Arduino-style APIs, but follows a modular C++ firmware layout. ### Development Environment ```text VS Code + PlatformIO ``` PlatformIO is recommended because it provides: - repeatable builds, - dependency management, - cleaner modular project structure, - easier GitHub publishing, - better Serial Monitor control. ### Main Libraries #### TinyGPSPlus ```cpp #include ``` Used to parse GPS/NMEA data from the NEO-6M module. Provides: - latitude, - longitude, - speed, - altitude, - satellite count, - GPS fix validity, - data age. The project also manually parses ` $GPGSV ` / ` $GNGSV ` messages to display satellite PRN, SNR, elevation and azimuth. #### Adafruit GFX ```cpp #include ``` Used for graphics primitives: - text, - lines, - rectangles, - rounded rectangles, - colored panels, - UI layout. #### Adafruit ILI9341 ```cpp #include ``` Used to drive the 2.8-inch SPI TFT screen. #### WiFi ```cpp #include ``` Used to create the ESP32-C6 local Wi-Fi access point. #### WebServer ```cpp #include ``` Used to serve the local dashboard and JSON API. --- ## PlatformIO Setup Example ` platformio.ini `: ```ini [env:esp32c6] platform = https://github.com/pioarduino/platform-espressif32.git#develop board = esp32-c6-devkitc-1 framework = arduino upload_port = COM3 monitor_port = COM5 monitor_speed = 115200 upload_speed = 460800 monitor_rts = 0 monitor_dtr = 0 lib_deps = mikalhart/TinyGPSPlus adafruit/Adafruit GFX Library adafruit/Adafruit ILI9341 adafruit/Adafruit BusIO build_flags = -DARDUINO_USB_CDC_ON_BOOT=1 -DARDUINO_USB_MODE=1 ``` ### Notes for ESP32-C6 ESP32-C6 Arduino support may require the ` pioarduino ` platform. If you see: ```text Error: This board doesn't support arduino framework! ``` use the platform line shown above. --- ## Build, Upload and Monitor Clean build: ```powershell pio run -t clean ``` Build: ```powershell pio run ``` Upload: ```powershell pio run -t upload ``` Monitor: ```powershell pio device monitor -p COM5 -b 115200 ``` If COM5 disconnects randomly, try: ```ini monitor_rts = 0 monitor_dtr = 0 ``` --- ## TFT Dashboard The TFT dashboard is designed for field usage and shows the most important status without requiring a laptop. Main sections: ### GNSS Panel Shows: - GPS state: ` WAIT `, ` DATA `, ` FIX `, - used satellites, - visible satellites, - mode, - latitude, - longitude. ### LoRa Radio Panel Shows: - LoRa state, - TX state, - last TX status. ### NMEA Stream Panel Shows: - NMEA character count, - GNSS stream activity, - useful debug status. ### Satellite Panel Shows: - GPS PRN numbers, - SNR values, - active satellite list. Example: ```text G05:24 G12:41 G21:38 G29:15 ``` Where: - ` G05 ` = GPS PRN 05, - ` 24 ` = signal-to-noise ratio. --- ## Web Panel The ESP32-C6 starts a local Wi-Fi access point. Default credentials: ```text SSID: GPS-TRACKER-T1 PASS: 12345678 URL : http://192.168.4.1 ``` The web panel displays: - GPS state, - latitude and longitude, - speed, - altitude, - satellite count, - visible satellites, - LoRa state, - TX state, - last LoRa packet, - RAK response, - satellite PRN/elevation/azimuth/SNR, - Google Maps link when GPS fix is available. ### JSON API The web dashboard reads: ```text /api/status ``` Example fields: ```json { "device": "T1", "firmware": "2.1.0", "gpsState": "FIX", "fix": true, "lat": "39.963205", "lon": "32.791445", "speed": 1, "alt": 1024, "sat": 8, "gsv": 10, "nmea": 12000, "lora": "READY", "tx": "OK #12", "packet": "T1,FIX,39963205,32791445,1,8,1024,10,12,NORMAL" } ``` --- ## GNSS / Satellite Data The NEO-6M does not provide real satellite names such as official spacecraft names. It provides GPS PRN numbers. The firmware displays them as: ```text GPS-05 GPS-12 GPS-21 ``` Satellite information parsed from GSV: | Field | Meaning | | --- | --- | | PRN | Satellite identifier | | Elevation | Degrees above horizon | | Azimuth | Direction in degrees | | SNR | Signal strength / carrier-to-noise value | ### GPS States | State | Meaning | | --- | --- | | ` WAIT ` | No NMEA data received | | ` DATA ` | NMEA data is coming, but no valid fix | | ` FIX ` | Valid position is available | If NMEA count increases but latitude/longitude are not available, GPS is working but has no fix yet. --- ## LoRa P2P Protocol StratoTrack uses raw LoRa P2P through RAK RUI3 AT commands. RAK setup commands: ```text AT AT+NWM=0 ATZ AT AT+P2P=868100000:12:125:0:8:14 AT+PRECV=0 ``` Send command: ```text AT+PSEND= ``` The RAK module expects HEX payload for P2P send. Therefore, the firmware converts: ```text T1,FIX,39963205,32791445,1,8,1024,10,12,NORMAL ``` to HEX before sending. --- ## Packet Format Current packet format: ```text ID,STATE,LATx1e6,LONx1e6,SPEED,SAT,ALT,GSV,COUNTER,MODE ``` Example: ```text T1,FIX,39963205,32791445,1,8,1024,10,12,NORMAL ``` Field details: | Field | Example | Description | | --- | --- | --- | | ID | ` T1 ` | Device ID | | STATE | ` FIX ` | GPS state | | LATx1e6 | ` 39963205 ` | Latitude × 1,000,000 | | LONx1e6 | ` 32791445 ` | Longitude × 1,000,000 | | SPEED | ` 1 ` | Speed in km/h | | SAT | ` 8 ` | Used satellites | | ALT | ` 1024 ` | Altitude in meters | | GSV | ` 10 ` | Visible satellite entries | | COUNTER | ` 12 ` | Packet counter | | MODE | ` NORMAL ` | Device mode | ### Example Decoding ```text 39963205 / 1000000 = 39.963205 32791445 / 1000000 = 32.791445 ``` Google Maps: ```text https://maps.google.com/?q=39.963205,32.791445 ``` --- ## Second LoRa Receiver A second LoRa receiver can be built using another ESP32-compatible board and RAK3172/RAK3272S module. The receiver listens in LoRa P2P mode and decodes packets from the tracker. ### Receiver Wiring | RAK3172 / RAK3272S | Receiver MCU | | --- | --- | | UART2\_TX | GPIO4 | | UART2\_RX | GPIO5 | | 3V3 | 3V3 | | GND | GND | ### Receiver LoRa Config Must match the tracker: ```text 868100000:12:125:0:8:14 ``` ### Receiver Behavior The receiver: - starts RAK in P2P mode, - enables continuous receive mode, - waits for ` +EVT:RXP2P `, - extracts HEX payload, - decodes payload to text, - parses tracker packet, - prints coordinates, - prints Google Maps URL, - prints RSSI and SNR if available. Example output: ```text LORA PACKET RECEIVED RAW : T1,FIX,39963205,32791445,1,8,1024,10,12,NORMAL DEVICE : T1 STATE : FIX LAT : 39.963205 LON : 32.791445 MAP : https://maps.google.com/?q=39.963205,32.791445 SPEED : 1 km/h SAT : 8 ALT : 1024 m GSV : 10 COUNT : 12 MODE : NORMAL RSSI : -84 SNR : 10 ``` --- ## Configuration Main configuration file: ```text include/config.h ``` Important settings: ```cpp #define DEVICE_ID "T1" #define LORA_FREQ_HZ 868100000UL #define LORA_SF 12 #define LORA_BW 125 #define LORA_CR 0 #define LORA_PREAMBLE 8 #define LORA_TX_POWER 14 #define BEACON_INTERVAL_NORMAL_MS 10000UL #define WEB_AP_SSID "GPS-TRACKER-T1" #define WEB_AP_PASS "12345678" ``` ### Beacon Interval Default: ```cpp #define BEACON_INTERVAL_NORMAL_MS 10000UL ``` This sends one packet every 10 seconds. --- ## Field Testing Guide ### Step 1: Test TFT Confirm the TFT shows the dashboard. ### Step 2: Test GPS NMEA Serial should show: ```text NMEA increasing ``` If NMEA increases but GPS state is ` DATA `, GPS works but has no fix. ### Step 3: Get GPS Fix Move outdoors or near a clear window. Expected: ```text GPS FIX SAT 5+ LAT valid LON valid ``` ### Step 4: Test LoRa TX Expected: ```text RAK: +EVT:TXP2P DONE TX: T1,FIX,... ``` ### Step 5: Test Web Panel Connect to: ```text GPS-TRACKER-T1 ``` Open: ```text http://192.168.4.1 ``` ### Step 6: Test Second Receiver Power the second receiver and check for ` RXP2P ` events. --- ## Troubleshooting ### GPS stays WAIT Cause: - GPS TX not connected, - wrong GPS RX pin, - no common ground, - GPS not powered, - wrong baud rate. Check: ```text NMEA count = 0 ``` This means ESP32 receives no GPS data. ### GPS DATA but no FIX Cause: - GPS sees NMEA but no satellite lock. Fix: - go outside, - place antenna facing sky, - wait 2–5 minutes, - check satellite count. ### LoRa NO AT Cause: - wrong UART pins, - wrong baud, - no RAK power, - no common ground, - TX/RX swapped. ### LoRa P2P ERR Cause: - RAK accepted AT but rejected P2P config, - RAK may need reboot after ` AT+NWM=0 `, - previous mode not applied yet. Fix: - use ` AT+NWM=0 `, - then ` ATZ `, - wait, - send ` AT `, - send ` AT+P2P=... `. ### LoRa TX works but receiver gets nothing Check: - same frequency, - same SF, - same bandwidth, - same coding rate, - same preamble, - antennas connected, - both devices use P2P mode, - receiver uses ` AT+PRECV=65534 `. ### Web panel does not open Check: - phone connected to ` GPS-TRACKER-T1 `, - password is ` 12345678 `, - open ` http://192.168.4.1 `, - disable mobile data if the phone switches away, - confirm Serial Monitor prints web panel start logs. ### COM5 disconnects Try: ```ini monitor_rts = 0 monitor_dtr = 0 ``` Use a better USB cable and avoid weak USB hubs. --- ## Safety and Legal Notes - Always connect a proper antenna before LoRa transmission. - Do not exceed local RF regulations. - For EU/Türkiye 868 MHz usage, respect regional duty-cycle and power limits. - This project is for educational, prototyping and field testing use. - Do not use for unlawful tracking or surveillance. --- ## Roadmap Planned improvements: - ACK packets from second receiver, - two-way LoRa commands, - SOS mode, - adaptive TX interval, - stopped/moving/fast mode detection, - local track history, - CSV export from web panel, - satellite skyplot on TFT, - battery voltage monitoring, - enclosure-ready hardware layout, - multi-device receiver dashboard. --- ## License AGPL-3.0 license --- ## StratoTrack LoRa Pro — kaynak ve uygulama notları ### Proje ve belgeyi birlikte değerlendirin Bu kayıt için kaynak açıklama korunmuştur. Kurulum, bağımlılık ve lisans kararlarında bu kayda bağlı proje ve dokümanı birlikte inceleyin; doğrulanmamış sürüm, ölçüm veya özellik bu ekle ilan edilmemiştir. ### Metinde geçen depo bağlantıları - [Depo bağlantısı](https://github.com/pioarduino/platform-espressif32.git) - [Depo bağlantısı](https://github.com/hamzadenizyilmaz/StratoTrack-LoRa-Pro) ### İlgili okuma yolu - [StratoTrack-LoRa-Pro Proje Dokümanı](/dokumanlar/github-stratotrack-lora-pro) - [LoRa Paket Kaybı Analizi](/blog/lora-paket-kaybi-analizi)