Raspberry Pi Weather Station

A real-time environmental monitoring system using Raspberry Pi, DHT11 sensor, and I2C LCD display.

Features

• Temperature and humidity monitoring using DHT11 sensor
• Real-time display on 16x2 I2C LCD screen
• Data logging with timestamp
• JSON file storage organized by date
• Automatic data collection every 5 minutes

Hardware Requirements

• Raspberry Pi (any model)
• DHT11 Temperature and Humidity Sensor
• 16x2 LCD Display with I2C backpack (PCF8574)
• Jumper wires (female-to-female)
• Breadboard (optional)

Wiring Instructions

DHT11 Sensor Connection:

1. VCC (Power) → 3.3V (Pin 1)
2. GND (Ground) → Ground (Pin 6)
3. DATA → GPIO4 (Pin 7)

I2C LCD Connection:

1. VCC → 5V (Pin 2)
2. GND → Ground (Pin 6)
3. SDA → GPIO2/SDA (Pin 3)
4. SCL → GPIO3/SCL (Pin 5)

Software Setup

1. Enable I2C interface on Raspberry Pi:

sudo raspi-config
# Navigate to Interface Options → I2C → Enable

2. Install required system packages:

sudo apt-get update
sudo apt-get install python3-pip git python3-smbus i2c-tools

3. Verify I2C LCD connection:

sudo i2cdetect -y 1

You should see the LCD address (usually 0x27) in the output.

4. Clone this repository:

git clone https://github.com/yourusername/room-weather-station.git
cd room-weather-station

5. Install Python dependencies:

pip3 install -r requirements.txt

6. Run the weather station:

python3 weather_station.py

Auto-start on Boot

1. Copy the service file to systemd:

sudo cp weather-station.service /etc/systemd/system/

2. Enable and start the service:

sudo systemctl enable weather-station
sudo systemctl start weather-station

Data Storage

Data is stored in JSON format in the data directory. Files are organized by date (e.g., weather_data_2024-01-20.json).

Each reading contains:

• Timestamp
• Temperature (°C)
• Humidity (%)

LCD Display

The 16x2 LCD display shows:

• Line 1: Current temperature in Celsius
• Line 2: Current humidity percentage

The display updates every 5 minutes along with data logging.

Monitoring the Service

Check service status:

sudo systemctl status weather-station

View logs:

journalctl -u weather-station

Troubleshooting

1. If the LCD doesn't display:

   • Check I2C address using sudo i2cdetect -y 1
   • Verify wiring connections
   • Ensure I2C is enabled in raspi-config

2. If sensor readings fail:

   • Check DHT11 wiring
   • Verify GPIO pin number in code matches your connection
   • Ensure proper power supply to Raspberry Pi