Manual
Table Of Contents
- Table of Contents
- Preface
- 1 Introduction
- 2 Creating and Redistributing LNS Device Plug ins
- 3 How Plug ins Work with Directors
- How Plug ins Are Represented in the LNS Object Server
- How Plug ins are Installed and Made Visible to LNS
- How Plug ins Implement the Registration Command
- How Plug ins Respond to Commands from a Director Other than Registration
- How Directors Launch and Manipulate Plug ins
- What Plug ins Do When They Run in Standalone Mode
- Responding to Property Reads and Writes
- Uninstallation Issues
- Appendix A Standard Plug in Commands
- Appendix B Standard Plug in Properties
- Appendix C Standard Plug in Object Classes
- Appendix D Standard Plug in Exceptions
The command scope of an action is indicated by the ComponentApps collection that the
command is in. If an action is in the ObjectServer object’s ComponentApps collection, the
action has object server-wide scope. If it is in a System object’s ComponentApps collection, the
action has system-wide scope. If it is in a DeviceTemplate object’s ComponentApps collection,
the action applies only to devices of that type. If it is in a LonMarkObject object’s
ComponentApps collection, the action applies only to functional blocks on devices of that type.
Registration Scope, Plug-in Scope
The Registration command is a special kind of command that must be supported by every LNS
plug-in It has either ObjectServer-wide scope (1) or System-wide scope (2). The scope of the
Registration command is also referred to as the plug-in scope.
Server
See
Registered Server.
Target Object
The LNS object on which a director has asked a plug-in to operate.
Windows Registry
The Windows registry is a shared resource on the computer that contains information about how the
computer runs. Among other functions, the registry provides a simple database-like mechanism that
allows programs to store and exchange information. Information in the registry is stored by key. You
can think of a key as being like a directory. Each key contains one or more values (just as a directory
contains files) and can contain additional keys (just as a directory can contain additional directories).
Each value is identified by a name and contains data. All keys have at least one value, named
(Default).