#open source plc

When it comes to PLC programming software, Codesys is certainly well-known, but there is more to learning industrial automation than just this one! The following two open source PLC software can help you start your automation journey at a low cost:

Beremiz: Flexible & Powerful, Geared Towards Complex Automation & Integration

Core Positioning: A complete, IEC 61131-3 standards-compliant Integrated Development Environment (IDE) for machine automation, emphasizing flexibility and protocol support.

Key Components:

IDE (Beremiz.py): Runs on the user's computer, supporting all five IEC 61131-3 programming languages. Its unique feature is using the MatIEC compiler to translate programs into C code, which is then compiled into machine code for the target platform using the standard GCC toolchain, enabling true cross-hardware-platform deployment.

Runtime (Beremiz_service.py): Implemented in Python or C, responsible for executing the compiled program and handling I/O communication. Supports Linux, Windows, and macOS.

Standout Advantages:

Robust Industrial Protocol Integration: Natively supports key industrial bus/communication protocols like Modbus, EtherCAT, CANopen, OPC UA, facilitating integration with various devices and upper-level systems.

Built-in HMI Development Tool (SVGUI): Allows designing and building Human-Machine Interfaces (HMI) directly within the IDE using SVG vector graphics, simplifying the visualization development process.

Deep Hardware Adaptation Potential: The C code compilation characteristic enables efficient operation on resource-constrained embedded platforms (e.g., ARM Cortex-M microcontrollers) and also supports more powerful systems.

Ideal Use Cases: Machine automation, systems requiring complex control logic, projects needing multi-protocol integration, teaching and research (especially combining compiler principles with real-time control), development of customized industrial controllers.

Official Website: https://beremiz.org/

OpenPLC: Lightweight & Versatile, King of Hardware Compatibility

Core Positioning: The first fully open-source (software + hardware reference) and IEC 61131-3 standards-compliant full-featured PLC solution.

Key Components:

Runtime: The core execution engine, extremely resource-efficient, perfectly suited for embedded devices and IoT edge nodes.

Editor: Intuitive and easy to use, supports all five IEC languages: Ladder Diagram (LD), Function Block Diagram (FBD), Instruction List (IL), Structured Text (ST), and Sequential Function Chart 

(SFC).HMI/SCADA Integration: Seamlessly integrates by default with the powerful open-source SCADA system ScadaBR (via Modbus/TCP communication), enabling convenient web-based monitoring.

Standout Advantages:

Extremely Wide Hardware Support: Ranges from entry-level Arduino (Uno, Nano, Mega), ESP8266/ESP32, to Raspberry Pi (RPi 2/3/4), industrial-grade platforms like Controllino, UniPi, Neuron PLC, and even Windows/Linux soft PLCs – covering almost everything!

Ideal for Security Research: Due to its open-source nature and industrial protocol implementations, it is widely used for learning, testing, and attack/defense drills in Industrial Control System (ICS) cybersecurity.

Ideal Use Cases: Home automation, small SCADA systems, low-cost industrial control prototypes, IoT edge control, ICS security experimentation platforms.

Official Website: https://autonomylogic.com/

Case Details

Beremiz is an open-source Integrated Development Environment (IDE) designed for Programmable Logic Controllers (PLCs), adhering to the IEC 61131-3 international standard. It supports multiple programming languages, including Ladder Diagram (LD), Structured Text (ST), Function Block Diagram (FBD), Instruction List (IL), and Sequential Function Chart (SFC). Beremiz provides an intuitive graphical programming interface, supports flexible data types, offers powerful debugging capabilities, and includes a simulation environment, allowing developers to test programs without physical hardware. Built on Python, C, and C++, Beremiz supports cross-platform operation on Windows and Linux systems and is widely used in industrial automation, equipment control, and data acquisition scenarios. Its open-source nature makes it highly extensible, enabling seamless integration with third-party tools and protocols for various industrial control needs.

Integration of ARMxy BL350 Embedded Controller with Beremiz

The ARMxy BL350 series embedded controller is a high-performance industrial control device based on the TI Sitara AM62x processor. It features a multi-core architecture (up to quad-core ARM Cortex-A53 at 1.4 GHz and a single-core ARM Cortex-M4F at 400 MHz), supports operating systems such as Linux-5.10.168, Yocto 3.1, and Ubuntu 20.04, and provides rich interfaces (e.g., 1–3 10/100M Ethernet ports, 2 USB 2.0 ports, optional HDMI 2.0, and various I/O expansion boards). Integrated with BLIoTLink industrial protocol conversion software, it supports protocols like Modbus, PLC, and MQTT, enabling seamless connectivity with mainstream IoT cloud platforms and SCADA systems. The BLRAT remote access tool further enhances remote operation and maintenance, making the BL350 ideal for industrial automation applications.

Combining Beremiz with the ARMxy BL350 leverages the strengths of both, creating an efficient and flexible industrial automation solution. Below are specific application scenarios and implementation methods:

Industrial Control and PLC Programming

The BL350’s multi-core architecture and extensive I/O interfaces make it an excellent platform for soft PLC applications. Beremiz, compliant with IEC 61131-3, can run PLC programs on the BL350, using Ladder Diagram or Structured Text to implement control logic. For example, in industrial control scenarios, developers can use Beremiz to design control logic and leverage the BL350’s X-series I/O boards (supporting RS485, CAN, DI/DO, etc.) for sensor data acquisition and actuator control. The BL350’s Cortex-M4F core handles real-time tasks, ensuring efficient execution of control programs.

Edge Computing and Data Acquisition

As an edge computing gateway, the BL350 supports Docker containers and Node-Red tools. Combined with Beremiz’s data processing capabilities, it enables complex data acquisition and processing tasks. In smart manufacturing, Beremiz can develop programs to collect analog (e.g., PT100 temperature sensor data) or digital signals via the BL350’s Y-series I/O boards and upload data to cloud platforms (e.g., AWS IoT Core or ThingsBoard) using the MQTT protocol. Beremiz’s simulation feature allows developers to validate logic during development, reducing debugging costs.

Motion Control and Real-Time Processing

The BL350’s Cortex-M4F and PRU-ICSS units provide hardware support for real-time motion control. Beremiz can be used to develop motion control algorithms, such as controlling motor speed via PWM output or implementing position feedback through pulse counting. In applications like Automated Guided Vehicles (AGVs) or industrial robots, Beremiz’s Sequential Function Chart (SFC) can design complex motion sequences, while the BL350’s multi-core architecture ensures real-time performance and high efficiency.

Remote Monitoring and Maintenance

The BL350’s integrated BLRAT remote access tool, combined with Beremiz’s debugging capabilities, enables remote deployment and monitoring of PLC programs. For instance, in Energy Management Systems (EMS/BMS), developers can write Modbus protocol control programs using Beremiz, deploy them on the BL350, and use 4G/WiFi modules for remote data transmission and program updates. This approach significantly improves equipment maintenance efficiency and reduces on-site operational costs.

Development and Debugging Workflow

Environment Setup: Install Linux-5.10.168 or Ubuntu 20.04 on the BL350 and configure the Beremiz runtime environment (requires Python and related dependencies).

Program Development: Use Beremiz’s graphical interface to design PLC programs, selecting appropriate programming languages (e.g., FBD or ST) for control logic.

Hardware Interface Configuration: Configure RS485, CAN, or other interfaces via the BL350’s X/Y-series I/O boards to ensure communication with external devices.

Simulation and Testing: Use Beremiz’s simulation feature to test program logic on the BL350, verifying input and output signal accuracy.

Deployment and Monitoring: Compile the program into an executable, deploy it to the BL350, and monitor remotely using BLRAT or SCADA systems.

Case Study: Application in Smart Manufacturing

In a smart manufacturing factory, the ARMxy BL350 paired with Beremiz was used for production line automation control. The BL350 was configured as BL350B-SOM352-X10-Y63, featuring 1 Ethernet port, 8GB eMMC, 1GB DDR4, and 2 RS485 interfaces. Beremiz was used to develop Ladder Diagram programs to control sensors and actuators on the production line. Data was uploaded to an Ignition SCADA system via the MQTT protocol using the BL350’s BLIoTLink software, enabling real-time monitoring. The BLRAT tool allowed engineers to remotely update PLC programs, significantly improving production efficiency and equipment maintainability.

Advantages Summary

High-Performance Hardware: The BL350’s multi-core architecture and rich interfaces support complex industrial applications.

Flexible Programming: Beremiz’s multi-language support and simulation capabilities streamline development.

Seamless Integration: BLIoTLink and BLRAT tools enable connectivity with cloud platforms and remote systems.

Industrial-Grade Reliability: The BL350 passes electromagnetic compatibility and environmental adaptability tests, operating reliably in extreme conditions from -40°C to 85°C.

Conclusion

The combination of the ARMxy BL350 embedded controller and Beremiz provides a robust hardware and software platform for industrial automation. Whether for industrial control, edge computing, or motion control, this combination delivers efficient and reliable solutions. Developers can leverage Beremiz’s open-source flexibility and the BL350’s hardware versatility to rapidly build customized industrial automation systems, meeting diverse needs in smart manufacturing, energy management, and IoT applications.