Arrangement and method for accessing data of a building automation system component

A method of providing user access to a controller, the method comprising:

• a) providing an external definition file, the external definition file including a first section that includes an application interface definition that defines a set of user interface displays and a second section that defines implementation of objects using protocol-specific data;
• b) employing a host application to create a first node comprising one or more objects based upon the protocol-specific data, the first node configured to communicate with the controller;
• and
• c) employing the host application to create a user interface element based on the application interface definition, wherein the user interface element is configured to:
• provide a user interface to data relating to the controller received from the first node and to receive user values via the user interface, and to provide the user values to the first node, wherein the first node is configured to convert the user values into information that, when provided to the controller, causes an action by the controller;
• d) generating first data in a first controller relating to a building control system;
• e) providing first information representative of the generated first data to the first node;
• f) employing the first node to process the first information to generate second information, wherein the process employed by the first node is defined in the external definition file;
• g) employing the interface object to display information representative of the second information.