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Mervis OS


Up-to-date Mervis OS image for Neuron units:

To install the Mervis OS into these units, continue with tutorial: Mervis on Unipi Neuron.

Contains Mervis tools and default ModbusTCP & SysFS drivers.

To install this OS, it is necessary to have an SD card with a capacity of at least 2 GB in the device. As of image version Mervis OS v2.4.0, Neuron units with Raspberry Pi 4 are also supported.


Previous OS images:


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.

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.

SSH is disabled on these OS images by default for security reasons.


V případě, kdy je třeba se k jednotce připojit přes SSH, lze jej povolit vytvořením souboru s názvem “ssh.txt” (popř. bez přípony .txt) a jeho umístěním do bootovacího oddílu SD karty, or by uploading configuration of Mervis RT.

The default SSH credentials are: user unipi and password unipi.technology.

After finishing work, it is necessary to turn off or secure SSH.

After flashing the new OS always upload I/O boards configuration. After uploading the configuration, wait approximately one minute for the drive to fully boot.