STM32L152RE Sensor Station

Overview

The STM32L152RE Sensor Station is an embedded system project that integrates multiple environmental sensors to collect, process, and visualize various environmental parameters. Built around the STM32L152RE microcontroller, it provides a platform for real-time environmental monitoring.

Web UI

Features

Supported Sensors

• LMT84LP: Temperature sensor
• DHT22: Temperature and humidity sensor
• NSL19M51: Light intensity sensor
• SGP30: Air quality sensor (VOC and CO₂)

Communication

• MODBUS protocol for sensor communication
• I2C interface for digital sensors
• UART interface for data transmission
• Python-based master application for data collection and visualization

MODBUS Implementation Details

The MODBUS implementation features:

• Fixed 8-byte frame size
• Efficient ring buffer for UART reception
• CRC16 verification for data integrity
• Frame validation and error handling
• Support for both raw and processed sensor data
• Customizable addressing scheme for each slave

Master Application Architecture

The Python-based master application provides:

• Modular sensor handling with dedicated classes for each sensor type
• Dynamic MODBUS frame construction and CRC calculation
• Real-time data processing and conversion
• Web-based visualization using Flask
• Responsive dashboard with real-time updates
• Sensor management interface

Project Structure

STM32L152RE-SensorStation/
├── src/
│   ├── Peripherals/        # Hardware interface drivers
│   ├── Sensors/           # Sensor-specific implementations
│   ├── Master/            # Python web application
│   └── main.c            # Main firmware entry point
├── Drivers/               # STM32 HAL and CMSIS
└── README.md             # This file

Hardware Requirements

• STM32L152RE Nucleo Board
• Supported Sensors:
  • LMT84LP Temperature Sensor
  • DHT22 Temperature/Humidity Sensor
  • NSL19M51 Light Sensor
  • SGP30 Air Quality Sensor
• Connection cables and breadboard

Software Requirements

Dependencies

• STM32 HAL Drivers
• CMSIS
• Flask (for web interface)
• Pyserial

Setup Instructions

Firmware

1. Clone the repository
2. Open the project in STM32CubeIDE
3. Build and flash to the STM32L152RE board

Web Interface

1. Navigate to the Master directory:

   cd src/Master

2. Install Python dependencies:

   pip install -r pyserial flask

3. Run the application:

   python app.py

4. Access the web interface at http://localhost:5000

Pin Configuration

Sensor	Pin	Interface
LMT84LP	PA0	ADC
NSL19M51	PA1	ADC
DHT22	PA7	Digital
SGP30	PB8/9	I2C

Usage

1. Power up the system
2. Access the web interface
3. Add sensors through the management interface
4. Monitor real-time data on the dashboard