====Data Linking / Binding====

Data linking (also known in ARDI as 'Binding') is the process of linking your [[properties|properties]] to external data, such as a historian or live source.

Each property on each asset can be connected to a different live and/or historical source for every [[contexts|context]] you have.

Before you can link to data, you'll need one or more [[data source|data sources]] created. These are assets that represent external sources of data. 

Once you've got a data source, you can....

===Open the Property Details for the Asset===

First, [[ardiuserguide:finding_an_asset|Find the asset]] you want to connect and open the [[detail_properties|property detail]] page.

{{detail_properties.png}}

===Click on the Link Button for the Property===

<faicon fa fa-link fa-5x>

Find the property you'd like to connect to live data, and press on the 'chain' ( <faicon fa fa-link> ) icon. This takes you to the page that allows you to connect data to the selected property.

===Choose the Type and Source of Data===

Now, choose the type (live / historical) and context that you want to set up. Most often, you'll be linking to **Actual Live** and **Actual Historical**.

{{linking_context.png}}

===Link to a Data Source===

Pick a data source from the droplist (the list will only contain those data sources appropriate for your chosen time-frame and context) to connect the property to external data. Depending on the [[driver]] being used, you might be asked to provide some additional information (lookup value, field name, IP address, memory register etc.).

{{linking_data.png}}

Once you've saved the information, the relevant drivers are restarted.

===Transform the Incoming Data===

Some information comes from the driver in a very raw state - this is usually very true of the **Modbus** protocol, where in the hardware every value is often scaled between 0 and 65535. 

When dealing with that sort of data source, **[[transforms]]** can be useful for making the value more human-readable. 

The 'Edit Transform' button only appears once you've created the link between your property and your external source.