Overview

Placed in a garden, on a trail, or at a campsite, the Heltec LoRa 32 V3 with a BME280 sensor can serve as a compact weather node, quietly recording temperature, humidity, and pressure. Through LoRa, it shares this data across the Meshtastic mesh, and with the Meshtastic app over Bluetooth, you can view the readings directly on your phone or relay them to other nearby nodes. Powered by a small battery packet, the setup runs on its own, providing a steady stream of local weather information without depending on Wi-Fi or cellular networks.

Hardware Components

• Heltec LoRa 32 V3
• BME280 Barometric Pressure, Temperature, & Humidity Sensor
• Jumper Wires
• Breadboard

Software Used

• Meshtastic App for Android/iOS
• Meshtastic Web Flasher
  
• Meshtastic Web Client

 

Application Discussion

Heltec LoRa 32 V3

WiFi LoRa 32 is a classic IoT dev-board designed & produced by Heltec Automation. The newly launched V3 version has the same pin sequence as the V2 version and retains Wi-Fi, BLE, LoRa, OLED display, and other functions.

BME280 Barometric Pressure, Temperature, & Humidity Sensor

GY-BME280 is a high-precision digital pressure, humidity, and temperature sensor module with I2C and SPI interfaces. It uses both I2C and SPI (supports 3-, 4-wire SPI) interface.

Specifications:

• Interface: I2C (up to 3.4MHz), SPI (up to 10 MHz)
• Temperature: -40 to 85 degrees Celsius
• Humidity: 0 to 100%
• Pressure: 300 to 1100 hPa
• Height: 0 to 30,000 feet
• I2C and SPI interface
• Operation: 3.3V / 5V
• 100% brand new and high quality.

Operational Range:

• Temperature: -40 to +85°C
• Humidity: 0-100%
• Pressure: 300-1100 hPa

Resolution:

• Temperature: 0.01°C
• Humidity: 0.008%
• Pressure: 0.18Pa

Accuracy:

• Temperature: +-1°C
• Humidity: +-3%
• Pressure: +-1Pa

I2C address:

• SDO LOW : 0x76
• SDO HIGH: 0x77

 

Jumper Wires

 

Breadboard

 

Meshtastic Setup

1. Flash the Heltec Lora V3 using Meshtastic Flasher.

 

2. Once flashed, connect the meshtastic node to a device using its bluetooth.

 

3. Go to radio configuration and select LoRa. Set the region to PH_915 and reboot. You may change the name of you meshtastic node using the app or website or leave it as is.

 

4. Setup your BME280 and wire the BME280 

 

5. In the Meshtastic app, go to radio configuration. Enable the environmental telemetry and reboot the Heltec LoRa v3. You can change the interval of the updates of environmental measurements.

 

6. Wait for the BME280 to measure temp, humidity, and pressure.

 

7. On the Meshtastic app, you can see the readings of the BME280.

 

Wiring Setup

 

Video Demonstration

Conclusion

The Heltec LoRa 32 V3 paired with a BME280 sensor and the Meshtastic app forms a lightweight and resilient autonomous weather node. It continuously measures temperature, humidity, and pressure, providing accurate insight into local conditions.

Using LoRa, the data can travel across a mesh network, reaching other nodes far beyond the range of Wi-Fi. At the same time, Bluetooth makes it easy to check readings directly on a phone through the Meshtastic app. With a rechargeable battery or solar power, the node can run unattended for extended periods.

Its compact, low-power design makes it suitable for remote locations, outdoor activities, or backyard projects. Altogether, it’s a practical way to stay connected to environmental data while exploring the possibilities of decentralized mesh communication, with room for future improvements such as adding GPS, expanding the sensor suite, or integrating alerts for an even more capable system.

Project Authors (Code Delta)

• Janine Ernie G. Cabuslay
• James Robert L. Machico
• Cheryl Lou B. Narvaez

References

• Heltec Website
• Meshtastic Website
• Youtube