ESP32 BME280 Environmental Monitor

This guide will walk you through building an ESP32-based environmental monitor using a BME280 sensor. The device will collect temperature, humidity, and pressure data and send it to your Telemetry Harbor instance for real-time visualization and analysis.

Repo Link: https://github.com/TelemetryHarbor/harbor-esp32-bme280

Hardware Requirements

Component	Description	Approximate Cost
ESP32	Development board (NodeMCU ESP32, WROOM, etc.)	$3.82 (AliExpress) / $9.90 (Amazon US)
BME280	Temperature, humidity, and pressure sensor module	$4.20 (AliExpress) / $8.99 (Amazon US)
Jumper wires	For connecting components	$0.42 (AliExpress) / $5.49 (Amazon US)
Micro USB cable	For power & programming	$3.00 (AliExpress) / $5.00 (Amazon US)
Optional	3.3V power supply for standalone deployment

Software Requirements

• Arduino IDE (1.8.13 or newer) or PlatformIO
• ESP32 board support package
• Required libraries:
  • Adafruit BME280 Library
  • Adafruit Unified Sensor
  • WiFi Library (built into ESP32 core)
  • HTTPClient Library (built into ESP32 core)
• Telemetry Harbor account (free tier available)

Wiring Diagram

Connect the BME280 sensor to the ESP32 using I2C:

BME280 Pin	ESP32 Pin	Function
VCC	3.3V	Power
GND	GND	Ground
SDA	GPIO 21	Data
SCL	GPIO 22	Clock

Setup

1. Hardware Assembly

1. Connect the BME280 sensor to the ESP32 according to the wiring diagram.
2. Connect the ESP32 to your computer via USB.

2. Software Setup

1. Install the Arduino IDE.
2. Add ESP32 board support by adding this URL in Preferences > Additional Boards Manager URLs:

   https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json

3. Install the required libraries via the Library Manager:
   • Adafruit BME280 Library
   • Adafruit Unified Sensor
4. Clone this repository or download the code.

3. Telemetry Harbor Configuration

1. Create a Telemetry Harbor account.
2. Create a new Harbor called "ESP32_Environmental_Monitor" (or your preferred name).
3. Select "General" harbor type and "Free" specification.
4. Copy your API Key and Harbor ID from the Harbor details page.

4. Configure and Upload the Code

1. Open the ESP32_BME280_Telemetry.ino file in Arduino IDE.
2. Update the following variables in the code:
   • WiFi SSID and password
   • Telemetry Harbor API Endpoint URL and API Key
   • Adjust the shipId and sensor reading interval if desired
3. Select your ESP32 board model from Tools > Board.
4. Select the correct COM port from Tools > Port.
5. Upload the code.

5. Visualize Your Data

1. Access your Telemetry Harbor account.
2. Navigate to the Harbor details page and copy your Grafana password.
3. Access the Grafana dashboard using the provided endpoint.
4. Login with your Telemetry Harbor email and the Grafana password.
5. Navigate to Dashboards and select the Comprehensive Telemetry Dashboard.
6. Use filters to view your specific sensor data.

Customization

Sensor Calibration

You can adjust the temperature and humidity offsets in the code:

const float temperatureOffset = 0; // Adjust as needed
const float humidityOffset = 0;    // Adjust as needed

Data Collection Interval

Modify the intervalMillis variable to change how frequently data is collected and sent:

const unsigned long intervalMillis = 60000; // 60000ms = 1 minute

Troubleshooting

Common Issues

• BME280 not found: Double-check wiring or try alternate I2C address (0x76 or 0x77).
• WiFi connection failure: Verify credentials and ESP32 WiFi capability.
• Data not appearing in Telemetry Harbor: Verify API key and URL are correct.

Debug Mode

For detailed debugging, monitor the serial output at 115200 baud in the Arduino IDE. This will show connection status, sensor readings, and API responses.