Live Mapping works with OPC Data Access ("Classic"), OPC XML-DA and OPC Unified Architecture servers (for data access). Its features include:

• You can map to any OPC item, node attribute or property.
• Different mapping kinds such as Value, Quality, Timestamps, ErrorMessage, and many more.
• Whole class can be mapped at once, or details can be specified on mapped members individually.
• Operations on mapped types can be narrowly targeted as needed using mapping tags.
• Relative OPC browse paths can be used to avoid necessity of mapping to absolute item or node IDs.
• Meta-members allow to relate the mapped object to its location in the address space, and parameters for operations.
• Pre-made node classes for easier mapping.
• Type-less mapping is also possible, for direct correspondence between the .NET members and OPC data.

The live mapping development model allows you to write objects that correspond logically to a functionality provided by whatever is “behind” the OPC data. For example, if part of your application works with a boiler, it is natural for you to create a boiler object in the code. You then describe how your objects and their members correspond to OPC data – this is done using attributes to annotate your objects. Using Live Mapping methods, you then map your objects to OPC data, and perform OPC operations on them.

For example, when you subscribe to OPC items, incoming OPC item changes can directly set corresponding properties in your objects, without any further coding. You can then focus on writing the code that handles these property changes, abstracting away the fact how they come in.

To give a concrete example, here is a piece of code of a .NET object annotated for live mapping with OPC Data Access, in C#:

    [DAType]
    class BoilerInputPipe
    {
        [DANode]
        public FlowTransmitter FlowTransmitter1 = new FlowTransmitter();

        [DANode]
        public Valve Valve = new Valve();
       
        [DANode, DAItem]
        public bool InAlarm { get; set; };
    }

You can use the Liver Mapping model with OPC Data Access, or with OPC Unified Architecture data.