RevPi Browsing

The logiccloud Control can be used to enable easier setup of the RevPi mappings using edge browsing functionality. This is done by installing a device-level service that reads the PiCtory configuration and sends browsing information to the portal.

The portal can then be used to browse the available RevPi signals and select the variables to be mapped.

The browsing service can be enabled temporarily while the mappings are being set up and then removed to reduce the load on the device.

Enabling the browsing service

To enable the browsing functionality, a dedicated browsing service must be installed on the edge device. This can be done from the logiccloud Control user interface by clicking on the pencil button next to the Device services table header:

A dialog will be shown where the browsing service can be enabled with a single click:

Once the changes are saved, the browsing service will be installed and started on the device. This will enable browsing functionality for this device.

Info

RevPi browsing can be done without having an actual runtime installed on the device.

Browsing the RevPi signals

Once the browsing service is enabled, the RevPi signals can be browsed from the portal.

To do this, a runtime with a RevPi connection and configuration must be created (see Creating a RevPi Connection for details).

Once the connection is added, the RevPi I/O can be browsed by clicking on the Browse button at the top:

This will open up the browsing dialog, and the device that has the browsing service can be selected:

On the left side, the tree can be expanded to explore the RevPi modules and their signals. The tree structure is:

• Module (e.g., DIO (31))
  • Inputs — input signals from the module
  • Outputs — output signals from the module
  • Memory — internal memory variables

Upon reaching the desired node, selecting it becomes possible with a click.

If the node contains children (a module or section), a table appears listing all the available variables. Selection can be done by clicking the plus button next to each variable, or by using the plus button at the top to select all variables at once:

The Selected items table shows all selected variables, and also allows removing any variable not desired in the final selection.

Once all desired variables are added to the Selected items, clicking on the Select button at the bottom will add them to the RevPi connection configuration:

Once the selection is confirmed, the mappings will be populated with the selected items. The PiCtory variable name, Direction, and Type are filled in from the device configuration.

Variable information

The browser displays the following information for each variable:

Column	Description
Name	PiCtory variable name of the signal
Data type	Default IEC 61131-3 data type based on the bit length
Bit length	Width of the signal in bits (1, 8, 16, or 32)
Direction	Input, Output or Memory: the PiCtory section the signal belongs to
Writable	Whether the signal can be written to (yes for outputs, no for inputs and memory)
Module	Name of the module the signal belongs to
Compatible data types	Other data types that can represent the signal

Data type mapping

The following table shows how the signal bit length maps to default and compatible data types. The default type carries the raw bit pattern without interpretation. To read a signed analog value, select INT instead of WORD (16-bit) or DINT instead of DWORD (32-bit) in the Type column after adding the variable.

Bit length	Default data type	Compatible data types
1	BOOL	—
8	BYTE	SINT, USINT
16	WORD	INT, UINT
32	DWORD	DINT, UDINT, REAL

Direction mapping

The mapping direction (how data flows in the connection) is determined by the signal direction on the module:

Signal Direction	Writable	Mapping Direction
Input	no	input (RevPi → PLC)
Output	yes	output (PLC → RevPi)
Memory	no	input (RevPi → PLC)

Adding variables to the mapping

To add variables from the browser:

1. Expand the module in the tree to see the sections (Inputs, Outputs, Memory)
2. Expand a section to list the available variables
3. Click the + button next to each variable, or use the Add all button to add all variables in the section
4. Review the selected variables in the Selected items table
5. Click Select to add them to the mapping

The mapping row will be pre-filled with:

• PLC variable: Filled in when the project has an access variable with the same name as the PiCtory variable. Otherwise it is empty, and you select the access variable from the list.
• PiCtory variable name: Filled in from the device
• Direction: Filled in based on the module signal direction
• Type: Filled in with the default type for the bit length

Variables with an unsupported bit length (not 1, 8, 16, or 32 bits) are shown in the browser but cannot be added to the mapping.

Disabling the browsing service

After the mappings are set up, the browsing service can be disabled to reduce the load on the device. This can be achieved from the logiccloud Control - Device services dialog by clicking on the pencil button and deselecting the browsing service. When the changes are saved, the browsing service will be stopped and removed from the device.

Troubleshooting

”Configuration file not found” or message mentioning linux-setup.sh

The browsing service cannot read the PiCtory configuration file /etc/revpi/config.rsc. Either the file does not exist on the device, or the setup script has not made it available to the logiccloud services. Devices that were set up before RevPi browsing was released do not have this access yet.

Solution:

1. Log in to the device with SSH.
2. Check that the file exists: ls -l /etc/revpi/config.rsc. If it does not exist, open PiCtory, save the configuration and reset the driver.
3. Run the logiccloud setup script linux-setup.sh again. It makes the PiCtory configuration readable (read only) for the logiccloud services.
4. Open the browse dialog again and press Force Refresh.

Device not listed in the browse dialog

The RevPi browsing service is not enabled or not running on that device.

Solution:

1. Go to Device services in logiccloud Control
2. Click the pencil button to edit services
3. Enable the RevPi browsing service
4. Wait for the service to start (usually a few seconds)
5. Refresh the browser dialog

Variable names changed in PiCtory do not appear

The browse dialog shows the tree it loaded when a node was first expanded.

Solution:

1. In PiCtory, save the configuration and reset the driver. The connector resolves names only after the driver reset.
2. In the browse dialog, press Force Refresh on the module or section that contains the variable.
3. Check that the new name appears.