IoT-project

Project summary 🔧

What this project does

• This is an IoT monitoring project using Heltec ESP32 LoRa boards to monitor environmental data on a surface or field.
• The project supports two device roles:
  • Main board (master): connects to Wi‑Fi, hosts a small web server (serves index.html from LittleFS), requests/receives sensor data over LoRa, displays info on the onboard OLED, and exposes a simple HTTP API (/api/data, /api/receive).
  • Field board (node): reads sensors (BME680 for temperature/humidity/pressure and TMG3993 for light), measures an analog water-level sensor, transmits readings via LoRa, and enters deep sleep to conserve power.

Key components

• Sensors: BME680 (temp/humidity/pressure), TMG3993 (light / lux).
• Communication: LoRa (RADIOLIB + SX12x family).
• Storage & UI: LittleFS for index.html, onboard OLED display for status.
• Power saving: Field nodes use deep sleep with timer and external wake.

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How to run the project (Main board vs Field board)

Common preparation

1. Install PlatformIO and open this project in VS Code.
2. Update Wi‑Fi credentials in include/main.h:

const char* ssid = "YourSSID";
const char* password = "YourPassword";

3. Connect sensors, LoRa antenna and any external wake hardware according to the wiring.

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Run as Main board (Wi‑Fi + Web server)

1. Configure the board to run as main:
   • Quick way: edit include/main.h and set:

const bool MAINBOARD = true;

• Alternatively, add a PlatformIO environment with -DMAINBOARD=1.

2. Upload LittleFS contents (serves index.html):

pio run -e heltec_wifi_lora_32_V3 -t uploadfs

3. Build and flash the firmware:

pio run -e heltec_wifi_lora_32_V3 -t upload

4. Open serial monitor to view IP and logs:

pio device monitor -e heltec_wifi_lora_32_V3 -b 115200

5. In a browser open http://<IP>/ or http://<IP>/api/data to view JSON data. The main board requests data from field nodes over LoRa (default ~60s) and shows it on the OLED.

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Run as Field board (low-power sensor node)

1. Ensure include/main.h has:

const bool MAINBOARD = false;

2. Verify sensor wiring and water-level analog input (pin 19 in code).
3. Build and flash firmware:

pio run -e heltec_wifi_lora_32_V3 -t upload

4. After flashing the field board will acquire sensors, send a LoRa payload (format: 0,temp,hum,pressure,light,water) and enter deep sleep (wakes every ~60 s or by external wake).

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Useful PlatformIO commands 🔁

• Build: pio run -e heltec_wifi_lora_32_V3
• Upload firmware: pio run -e heltec_wifi_lora_32_V3 -t upload
• Upload LittleFS: pio run -e heltec_wifi_lora_32_V3 -t uploadfs
• Serial monitor: pio device monitor -e heltec_wifi_lora_32_V3 -b 115200

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Notes & caveats ⚠️

• Water level needs calibration (code currently uses /530*100 placeholder).
• LoRa frequency and region settings (e.g., FREQUENCY = 866.3, REGION_US915) must be adjusted to local regulations.
• To avoid manual edits, consider adding two PlatformIO environments (e.g., env:main and env:field) with -DMAINBOARD=1/-DMAINBOARD=0 build flags to switch roles without changing source code.

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Next steps 💡

If you want, I can add env:main/env:field entries to platformio.ini and/or polish the LittleFS index.html UI. Just say which change you prefer.

If you have modifications advices or issues, we will be glad to respond