Review the Arduino Opta Micro-PLC

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Do you work with programmable logic controllers (PLC)? You are the ideal person to roadtest the Arduino Opta, secure micro, Programmable Logic Controller (PLC) with Industrial Internet of Things (IoT) capabilities.

Arduino Opta Micro-PLC

OptaTm is a secure micro Programmable Logic Controller (PLC) with Industrial Internet of Things (IoT) capabilities. Developed in partnership with Finder®, this device supports both the Arduino programming language and standard IEC-61131-3 PLC programming languages, such as Ladder Diagram (LD), Sequential Function Chart (SFC), Function Block Diagram (FBD), Structured Text (ST), and Instruction List (IL), making it an ideal device for automation engineers. Based on the STM32H747XI from STMicroelectronics®, a high-performance Arm® Cortex®-M7 + Cortex®-M4 microcontroller, OptaTm is a perfect option for a wide range of applications, from real-time control to predictive maintenance applications. 

OptaTm Variants

There are three variants of OptaTm created to fit the different needs of each industry and application. The main differences between each one of the variants are related to their connectivity possibilities. All the variants can be connected to the Cloud using the onboard Ethernet. If your solution does not need an RS-485 interface or wireless connectivity, OptaTm Lite can fit your needs. If you need to connect your device to a Modbus RTU bus using an RS-485 connection but do not need wireless communication, OptaTm RS485 is the chosen variant. To have all OptaTm features and flexibility, with full wireless Wi-Fi® and Bluetooth® Low Energy connectivity, the OptaTm WiFi variant is the perfect choice for your professional projects.

OptaTm Main Components

OptaTm features a secure, certified, and durable design that enables it for automation and industrial applications. Here's an overview of the device's main components:

Microcontroller:  At the heart of OptaTm is the STM32H747XI, a powerful and high-performance microcontroller from STMicroelectronics®. The STM32H747XI is built around an Arm® Cortex®-M7 and Arm® Cortex®-M4 32-bit RISC cores. The Arm® Cortex®-M7 core operates at up to 480 MHz, and the Arm® Cortex®-M4 core at up to 240 MHz.

Wireless connectivity: OptaTm (WiFi variant only) supports 2.4 GHz Wi-Fi® (802.11 b/g/n) and Bluetooth® Low Energy (4.2 supported by firmware and 5.1 supported by hardware), allowing the device to communicate wirelessly with other devices and systems. 

Ethernet connectivity: OptaTm (all variants) features an onboard, high-performance 10/100 Mbps Ethernet transceiver accessible through its onboard RJ45 connector.

Security: OptaTm features an onboard ready-to-use secure element, the ATECC608B from Microchip®, specifically designed for IoT devices that provides advanced security features, being perfect for Industrial IoT (IIoT) environments where security is critical. 

USB connectivity: OptaTm features an onboard USB-C® port that can be used for programming and data logging but not to command the relay outputs. To do so, power OptaTm using an external power supply. 

Analog and digital peripherals: OptaTm features analog and digital peripherals such as eight analog/digital input ports and four digital outputs ports (relay outputs). 

RS-485 connectivity: OptaTm (RS485 and WiFi variants) features a physical RS-485 communication interface available through an onboard terminal connector that can be used for standard communication interfaces like Modbus RTU or custom communication protocols. 

Form factor: OptaTm devices can be mounted standalone on a DIN rail, a grid, or a panel, providing quick and easy access to all input/output ports and peripherals.

OptaTm Core and Libraries

The Arduino Mbed OS Opta Boards core contains the libraries and examples to work with OptaTm's peripherals and onboard components, such as its input ports, output ports, Wi-Fi® and Bluetooth® module (WiFi variant only).

Arduino PLC IDE

PLC IDE is the Arduino solution to program OptaTm devices using the five programming languages recognized by the IEC 61131-3 standard.


  • Easy and fast software development, starting from ready-to-use Arduino sketches, tutorials and libraries
  • Support for standard IEC 61131-3 PLC languages
  • Fieldbus integration via Modbus TCP (ethernet) and Modbus RTU (serial RS485)
  • Seamless IoT connectivity (Ethernet/Wi-Fi/Bluetooth® Low Energy)
  • Real-time remote monitoring via intuitive Arduino Cloud dashboards (or third-party services)
  • Security at the hardware level thanks to onboard secure element and X.509 Standard compliance
  • Secure OTA firmware updates and Cloud device management
  • High-power relay switching (4 x 2.3 kW)
  • Reliable by design, thanks to industrial certifications and Finder’s expertise in switching technology
  • Easy to install, with DIN rail compatibility


RoadTester Instruction

  • The preferred way to test it would be to use it with something you are currently working on.
  • Otherwise, working with the documentation, open the box and test the out of the box experience. Show the reader of this review what you discovered utilizing text, images, videos, and/or any other media, so the reader understands what is involved in using the product.


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June 28 2024

End enrollment

August 09 2024

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August 13 2024

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