Problem Statement

Modern embedded systems increasingly require graphical interfaces to display system status, sensor data, and operational information in a clear and intuitive way. These interfaces are commonly referred to as Human–Machine Interfaces (HMI).

An HMI is the interface that allows a human operator to interact with a machine, system, or process by presenting information visually and enabling control actions. In industrial environments, HMIs typically display real-time data, alarms, and system states, allowing operators to monitor and control machines efficiently.

What is an HMI?

Human–Machine Interfaces are widely used in industrial automation, instrumentation, robotics, smart appliances, and many other embedded applications. They serve as the communication layer between humans and machines, translating complex system data into visual elements that are easy to interpret and interact with.

Examples of typical HMI visual components include:

  • Status indicators
  • Numeric displays
  • Graphical bars
  • Alarms and notifications
  • Control buttons and switches

Through these elements, operators can monitor machine behavior, analyze sensor data, and adjust system parameters in real time.

Challenges in Embedded HMI Development

Despite their importance, implementing graphical interfaces in embedded systems remains challenging. Most embedded HMIs are currently implemented using software running on general-purpose microcontrollers or embedded processors. This approach often requires significant computational resources and complex firmware to handle:

  • display timing generation
  • graphical rendering
  • communication with sensors and controllers
  • real-time data processing

In resource-constrained systems, these tasks compete with the primary functionality of the embedded application, increasing firmware complexity and reducing system efficiency.

Another common limitation is the lack of flexible and reusable hardware platforms for building custom interfaces. Many commercial HMI solutions rely on proprietary ecosystems or fixed display modules that limit customization. As a result, developers often need to design new interface logic for every project.

Heterogeneous Signal Sources

Real-world embedded systems frequently interact with both analog and digital signals. Analog signals may represent physical quantities such as:

  • temperature
  • pressure
  • voltage
  • current
  • sensor amplitudes

Digital signals may originate from:

  • microcontrollers
  • communication interfaces
  • counters and timers
  • control logic

Transforming these heterogeneous signals into a responsive graphical interface typically requires additional software layers, external processing units, or specialized display modules.

Need for an Open Hardware Interface Platform

A reusable open-source hardware solution capable of generating graphical interfaces directly in hardware could significantly simplify the development of embedded HMIs.

Such a platform would allow developers to:

  • design a custom interface visually
  • connect real-world signals to the system
  • render graphical elements directly in hardware
  • reduce firmware complexity
  • accelerate development of monitoring and control systems

Providing an open and reproducible architecture for embedded HMIs can enable faster development of industrial, commercial, and edge-IoT devices, while also making advanced visualization capabilities accessible to a broader engineering community.

Target Users

Lacerta is designed for developers and organizations that need to build embedded graphical interfaces efficiently while minimizing firmware complexity. By implementing the interface rendering engine directly in hardware, Lacerta enables systems to visualize real-time data without relying on complex software display frameworks.

Embedded System Developers

Engineers developing embedded devices can use Lacerta to create graphical dashboards that display sensor readings, system states, or operational parameters. The hardware-based rendering engine offloads graphical processing from the main processor, simplifying firmware development and improving system performance.

Industrial Automation Engineers

Industrial systems often require visual monitoring panels to display machine status, process variables, alarms, and operational metrics. Lacerta provides a low-cost platform for implementing custom human–machine interfaces in industrial monitoring and control systems.

IoT and Edge Device Designers

Edge devices frequently collect data from distributed sensors and require simple local visualization capabilities. Lacerta enables the development of customizable dashboards that present real-time sensor information in applications such as environmental monitoring, smart infrastructure, and connected devices.

Product Developers and Hardware Startups

Product development teams can use Lacerta to accelerate the creation of embedded graphical interfaces for electronic devices. By reducing the need for complex display firmware, Lacerta shortens development cycles and simplifies system integration.

Researchers and Educators

Lacerta also serves as an educational platform for exploring digital design, embedded systems, and human–machine interface development using open-source hardware tools and reproducible ASIC design flows.