Weather Station
The weather station is built around the ESP32 microcontroller, which serves as the main system controller. The Nextion 3.5" HMI (Human-Machine Interface) display provides a dedicated operator interface for real-time monitoring of weather and environmental data.
Project scope
- ESP32 as the main system controller
- Nextion 3.5" HMI - dedicated operator interface
- Weather and environmental data visualization
- Password-protected access to advanced settings
- Network integration and remote access to data
- 3D printed enclosure, custom assembly and soldering
OT / IoT Security
- Segmentation of access to the system interface
- Device and configuration hardening
- Control of exposed system interfaces
- Protection of configuration and system parameters
- Basic resilience against common IoT attack vectors
Lessons learned from the project
Building my own weather station was both an interesting challenge and a valuable learning experience. Most of the time was spent designing a clear and intuitive graphical HMI interface that allows real-time monitoring of environmental parameters.
HMI (Human-Machine Interface) is one of the key components of OT systems. Through this interface, operators supervise technological processes and make operational decisions.
A poorly designed or improperly secured HMI can pose a serious threat to system stability. Granting excessive privileges to users or lacking proper access control mechanisms may lead to unauthorized changes to process parameters.
In industrial environments such a situation may result in system failure, interruption of the technological process, or even a prolonged production outage.
That is why even in laboratory or hobby projects it is worth applying good practices known from OT systems: access segmentation, the principle of least privilege, and configuration change monitoring.
Next development stage
In the next stages I plan to conduct penetration testing and further system hardening. The project will also be used to simulate attack scenarios targeting the OT/IoT layer and to analyze potential threat vectors in industrial environments.
Q&A: Weather Station
What is HMI?
HMI (Human-Machine Interface) is an operator panel that allows a person to interact with a machine or system. In OT environments, HMI displays process data and accepts user input, often via a touchscreen. In this project, a Nextion 3.5" display with resistive touch serves as the HMI, providing real-time weather data visualization and touch-based navigation between screens.
What is ESP32?
ESP32 is a low-cost, low-power microcontroller with built-in Wi-Fi and Bluetooth, widely used in IoT projects. It supports multiple communication protocols and offers enough processing power to handle sensor data acquisition, network connectivity, and serial communication with external devices such as HMI panels.
How does the display communicate with the microcontroller?
The Nextion HMI display communicates with the ESP32 via UART (Universal Asynchronous Receiver-Transmitter) serial interface. The connection uses GPIO16 (RX) and GPIO17 (TX) at a baud rate of 115200. This allows bidirectional data exchange: the ESP32 sends sensor readings and commands to the display, while the display sends touch events and user input back to the microcontroller.