KUNBUS Revolution Pi

If your logiccloud Control Runtime is running on a KUNBUS Revolution Pi, you can access the local I/O through the piControl driver. To do this, a new connection of type RevPi must be created.

Prerequisites

Before creating a RevPi connection, you need:

1. A KUNBUS Revolution Pi with the piControl driver installed and running
2. A PiCtory configuration saved to the device
3. The device-level RevPi setup script (linux-setup.sh) executed at least once
4. The piControl driver restarted after any changes to the PiCtory configuration

Creating a RevPi Connection

1. In your project, navigate to the Runtimes section
2. Select your runtime and expand Connections
3. Click Add connection and select RevPi
4. Fill in the connection details:

• Connection name: Name of the connection
• Connection description: Description of the connection, optional
• Poll interval: Interval in milliseconds at which the RevPi I/O are read and written to (default: 50 ms)

5. Click Save to create the connection

Mapping process variables

The process variables can be mapped to RevPi signals via the mappings table. To do this, either add individual variables or use the Browse feature to select variables from the device.

The mappings table has the following columns:

Column	Description
PLC variable	Name of the LogicCloud access variable
PiCtory variable name	Name of the signal in PiCtory (must match exactly, maximum 31 characters)
Direction	Direction of data flow: input (RevPi → PLC) or output (PLC → RevPi)
Type	IEC 61131-3 data type: BOOL, BYTE, SINT, USINT, WORD, INT, UINT, DWORD, DINT, UDINT, REAL

Naming rules

Variable names in PiCtory must:

• Match the exact name in PiCtory (case-sensitive)
• Be at most 31 characters
• Follow the pattern ^[A-Za-z][A-Za-z0-9_.]*$ (start with a letter, then letters, digits, underscores or dots)

A name that does not match any variable in PiCtory is silently skipped by the connector on the device and only logged there. The cloud cannot verify a name that you type by hand, so check the device logs if a mapping does not work. To avoid typing mistakes, use Browse to pick names directly from the device.

IN_OUT access variables

One signal may be mapped twice: once as input and once as output. This enables read/write access to the same variable (IN_OUT access in IEC 61131-3).

Poll interval

The poll interval sets how often the connector reads and writes RevPi I/O. The default is 50 milliseconds, which matches the Raspberry Pi connector. For most applications this is sufficient. Lower values increase CPU usage; higher values reduce responsiveness.

Browsing RevPi signals

To simplify mapping setup, use the Browse feature to browse available signals on the device. See RevPi Browsing for details.