Virtual item definitions

Virtual items are used like any other server item, except for one detail: they are not connected to any real datapoint on bus level. They can be used to store data. They may be connected to a any other server item.

File location of configuration:

<WorkspaceDirectory>\DataFiles\nxaVirtualItems.40.dat

#

Name

M/O

Descrition

#

Name

M/O

Descrition

1

Name

M

Name of the virtual item. Together with the path it must be unique.

2

Path

O

Specifies the path of the virtual item. Delimiter between sections of the path is the backslash \.

3

Description

O

Description of the virtual item. It will be displayed in the item tree.

4

Data Type

M

Possible data types are BOOL, STR, BYTE, CHAR, INT8, UINT8, INT16, UINT16, INT32, UINT32, INT64, UINT64, FLOAT, DOUBLE, DATE, TIME.

5

Access Rights

O

Allowed operations on the virtual item:

  • RW: read-write (default)

  • R: read-only

  • W: write-only

6

Persistent

O

Specifies whether the value of the virtual item is persistent (restored from the database after server start up ) or not. Default is F (non-persistent).

7

Synchronize

O

If set to "T", the value is synchronized between the main and backup server (if present). Default is F (no synchronization).

This applies only to main/backup configurations of the NETx Server.

8

Link Item ID

O

If a connection to another item is necessary the item ID of this one has to be placed here (bidirectional link between Virtual item and Linked item).

9

Script For OnReceive

O

Implement any LUA script here which shall be called by the OnReceived event.

10

Script For OnSend

O

Implement any LUA script here which shall be called by the OnSent event.

11

Script For OnSet

O

Implement any LUA script here which shall be called by the OnSet event.

12

Comment

O

Optional comment of the virtual item definition. The value is only used for documentation purposes.