Data Items

 

A Data Item represents a register in the device or a range of registers. A symbolic name and description is associated with the data item. An OPC client can obtain the data item description.

 

The actual OPC item name (tag) is compounded from the Address Space root, the names of the folder and its subfolders, and the name of the data item. Data items can be located in any folder, even in the root of the address space.

 

To Add a New Data Item:

  1. From the Project Explorer, click on a device under the Address Space node, then Add DataItem, as shown below.

New Data Item from the Project Explorer

 

-OR-

 

Select a device under the Address Space node in the Project Explorer, then click on the Add Data Item button (shown below) in the Edit section of the Home ribbon in the Workbench.

 

Add Data Item Button

  1. This opens the New Data Item properties in the right side of the configurator, as shown below. In the Data Item Name field, specify a logical name for the data item (Setpoint, Param001, ON_OFF, etc).

New Data Item Properties

 

Read Only

Read / Write

1 bit

Input

Coil

16 bit

Input Register

Holding Register

Vector, Bit Access, Simulations, Conversions

See Also:

Address Space

About Modbus Configurator