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OS Images

This section contains OS images for our controllers.

Mervis OS are versioned the same way as Mervis IDE releases. Eg. Mervis OS 2.3.0.x will work with IDE 2.3.0 but might not work with IDE 2.2.0. Mervis IDE 2.3.0 requires Mervis OS 2.2.0.x at least, but also requires update of the Mervis RT. Compatibility with Mervis OS older than 2.2.0 is not guaranteed.

If you uploaded a new OS image into your controller, it will automatically update its internal firmware during the first startup. That said, make sure to wait a few minutes after starting up the PLC. Disconnecting the power during the firmware update would cause the firmware to be corrupted. In such a case, the controller would have to be shipped back to the manufacturer for firmware re-flash.

Unipi Patron

  • To install the Mervis OS into these controllers, you can use one of Flashing the OS methods.

Unipi Axon

  • To install the Mervis OS into these controllers, you can use one of Flashing the OS methods.

Unipi Neuron/1.1

  • Installation on these controllers is indirect, as the OS is burned onto an mSD card with the card insterted into the PLC afterwards. Full description of the process is available in the Mervis on Unipi Neuron / 1.1 tutorial.

Unipi Gate

  • To install the Mervis OS into these gateway device, you can use one of Flashing the OS methods.

Every PLC with Mervis OS 2.3.0 and newer requires a license. If the PLC is not licenced, it will run in demo mode. The demo mode does not limit the functionality, but the program will run only for 20 minutes. After that time, the program will stop running and RUN LEDs will start blinking in a 2-second interval (on/off). Make sure to Update Runtime at first and then license the PLC.

The factory default Debian-based OS for Patron controllers. Pre-installed by default on all Patron controllers

Patron Mervis OS

Contains Mervis tools and default ModbusTCP & SysFS drivers.

Up-to-date Mervis OS image for Patrons

Patron Node-RED OS

To make the Node-RED installation process as easy as possible, we created a pre-assembled OS image containing everything that's needed for a successful Node-RED launch. The OS is based on Debian OS and included all required drivers for Patron controllers (kernel driver, overlay, RTC support, Modbus TCP, SysFS, EVOK).

A quick-start and installation guide is available at this link

The SSH is enabled by default. The username is: unipi and password is: unipi.technology.

Patron OpenSource OS

Image for development or OEM use. Includes ModbusTCP&SysFS drivers.

The SSH is enabled by default. The username is: unipi and password is: unipi.technology.

The factory default Debian-based OS for Axon controllers. Pre-installed by default on all Axon controllers

Axon Mervis OS

Contains Mervis tools and default ModbusTCP & SysFS drivers.

Up-to-date Mervis OS image for Axons

Axon Node-RED OS

To make the Node-RED installation process as easy as possible, we created a pre-assembled OS image containing everything that's needed for a successful Node-RED launch. The OS is based on Debian OS and included all required drivers for Axon controllers (kernel driver, overlay, RTC support, Modbus TCP, SysFS, EVOK).

A quick-start and installation guide is available at this link

The SSH is enabled by default. The username is: unipi and password is: unipi.technology.

Axon OpenSource OS

Image for development or OEM use. Includes ModbusTCP&SysFS drivers. EVOK should be installed using the apt, according to the guide on its GitHub page.

The SSH is enabled by default. The username is: unipi and password is: unipi.technology.

Neuron Mervis OS

An up-to-date Mervis OS image to be deployed to a SD card for Neuron controllers running Mervis RT.

As of image version Mervis OS v2.4.0, Neuron controllers with Raspberry Pi 4 are also supported.


Previous images only for Neuron controllers

Previous images of Mervis OS for Neuron and also UniPi 1.

To install this OS, it is necessary to have an SD card with a capacity of at least 2GB in the device. In Mervis OS version 1.7 and newer, the SSH communication protocol is disabled by default and must be enabled by creating a file named “ssh.txt” (or without the .txt suffix) and placing it into the SD card boot directory. Alternatively, you can do so by uploading configuration in Mervis IDE.

The default SSH login is: user unipi, password unipi.technology. We strongly recommend to change the login immediately after enabling SSH.


Neuron Node-RED OS

To make the Node-RED installation process as easy as possible, we created a pre-assembled OS image containing everything that's needed for a successful Node-RED launch. The OS is based on Debian OS and included all required drivers for Neuron controllers (kernel driver, overlay, RTC support, Modbus TCP, SysFS, EVOK).

A quick-start and installation guide is available at this link

To install this OS, it is necessary to have an SD card with a capacity of at least 4GB in the device. The SSH is enabled by default. The username is: unipi and password is: unipi.technology.


Neuron OpenSource OS

Image for development or OEM use. Includes ModbusTCP&SysFS drivers. Evok should be installed using the apt, according to the guide on its GitHub page.

The SSH is enabled by default. The username is: unipi and password is: unipi.technology.

To install this OS, it is necessary to have an SD card with a capacity of at least 2GB in the device.


Operating systems for Unipi Gate are based on the Debian OS. Gate series devices are shipped with the Node-RED image by default.

Gate Mervis OS

Contains Mervis tools and default ModbusTCP & SysFS drivers.

Up-to-date Mervis OS image for Gates

Gate Node-RED OS

To make the Node-RED installation process as easy as possible, we created a pre-assembled OS image containing everything that's needed for a successful Node-RED launch. The OS is based on Debian OS and included all required drivers for Unipi Gates.

A quick-start and installation guide is available at this link

The SSH is enabled by default. The username is: unipi and password is: unipi.technology.

Gate OpenSource OS

A clean OS image for development or OEM use.

The SSH is enabled by default. The username is: unipi and password is: unipi.technology.

Unipi 1.1 Mervis OS

An up-to-date Mervis OS image to be deployed to a SD card for UniPi 1 controllers (Unipi 1.1 and Unipi 1.1. lite) running Mervis RT.

As of image version Mervis OS v2.4.0, the combination with Raspberry Pi 4 is also supported.


Previous Mervis OS images only for Unipi 1.1/Lite

In the previous Mervis OS versions, the Unipi 1.1 controllers shared OS image with the Neuron line. See Neuron - UniPi Mervis OS.

To install this OS, it is necessary to have an SD card with a capacity of at least 2GB in the device. In Mervis OS version 1.7 and newer, the SSH communication protocol is disabled by default and must be enabled by creating a file named “ssh.txt” (or without the .txt suffix) and placing it into the SD card boot directory. Alternatively, you can do so by uploading configuration in Mervis IDE.

The default SSH login is: user unipi, password unipi.technology. We strongly recommend to change the login immediately after enabling SSH.

Unipi 1.1 Node-RED OS

To make the Node-RED installation process as easy as possible, we created a pre-assembled OS image containing everything that's needed for a successful Node-RED launch. The OS is based on Debian OS and included all required drivers for Unipi 1.1 controllers (kernel driver, overlay, RTC support, Modbus TCP, SysFS, EVOK).

A quick-start and installation guide is available at: this link

To install this OS, it is necessary to have an SD card with a capacity of at least 4GB in the device. The SSH is enabled by default. The username is: unipi and password is: unipi.technology.


Opensource images

We do not provide the ready opensource image (Like UniPian) for the first generation of UniPi. Please use the standard Raspbian Lite with Evok installed according to the guide on its GitHub page.

FHEM software image (obsolete)