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Enhanced DDL Features

The DDL enhancements include improved data visualization and display capabilities – like waveforms and valve signatures, a standardized method to access historic measurement or device performance information and enhanced tools for high-level information (such as algorithmic relationships for complex device parameters) display and use in host systems.

DDL enhancements include an improved user interface with support for menus (windows, tabs and groups) and added graphic support for graphs, charts and dial indicators. The enhanced DDL further standardizes the user interface for managing intelligent devices and eliminates the need for Windows resource files, supplemental files, and other DD modifications previously required by some asset management applications.

Description of the Data
it is possible to describe device parameters and parameters for additional information in the DD. The following data types are supported: floating point and fix point numbers, enumerations, byte and bit arrays, date, time, text, etc. The DD elements COLLECTION, BLOCK, ARRAY, ITEM_ARRAY and RECORD are used to represent the device model and data structures.

Description of the Communication
In the DD communication command, error handling, error texts, the order of the commands and the timing conditions are described.

The DD Application provides possibilities for the communication. E.g. point to point communication, communication via a gateway, communication via a automation system. An example for a gateway communication is the communication to a HART device via a Remote I/O. This communication protocol is defined in the “HART on PROFIBUS” PROFIBUS specification.

Open for diverse use
In addition to defining device parameters, the DD allows to describe information for catalog, e-commerce and asset management systems.

The description of the user interface can be used to generate a user interface e.g. on PC’s or hand held computers.

Additional Features of the DDL

Methods can be implemented in the programming language „C“ for transformations, sequences of operations, dependences
Multi language support in the DD and in separate dictionaries
DDL supports the complete or partial use of other DDs and reuse of own elements
It can use libraries of DDs for standard behaviors and device profile implementations
A C-Preprocessor DDL supports macros, Include files, compiler switches, etc.
The behavior and structure of the user interface and variables can be controlled at runtime with conditional expressions