This document provides a summary of the parts of LCA useful for SAIDA.
1 Data Server
1.1 Overview
1.1.1 Using the Object Server for Data Access
The data server may be used directly instead of using the object server to increase performance, but applications should use the object server. The object server automatically sets up the data server. The object server also creates and deletes data server objects.
1.1.2 Monitoring Network Variables
Network variables may be monitored by polling or by event-driven updates. This is however not yet implemented.
1.2 Data Server Interfaces
The data server provides functions for setting and getting network variables.
2 LCA Object Server
2.1 Overview
The LCA object server is a hierarchy of objects. The most important objects in the hierarchy is the AppDevice, NetworkVariable and SuperNode objects.
2.2 AppDevice
An AppDevice object represents a single LonWorks application node. Methods in the AppDevice object include Build, Load and Reset. An AppDevice object contains a collection of NetworkVariable objects.
2.3 SuperNode
A SuperNode object represents a logical grouping of other SuperNode and AppDevice objects. There is also a Parent property in the SuperNode object pointing to the parent SuperNode object.
2.4 NetworkVariable
Network variables are represented as objects in the object server. The properties of the NetworkVariable object include type (SNVT or user-defined) and value. There are also methods for adding and removing network variable objects.
3 Database Support
The database support in LCA is not yet implemented.
4 Datatypes
There are two categories of datatypes, SNVT datatypes and user-defined datatypes. These datatypes are defined in two separate files (one for SNVT and one for user-defined datatypes).
4.1 SNVT
SNVT is short for Standard Network Variable Types. This standard contains a large amount of different datatypes. Every datatype has a defined range and interpretation.
© 1996, The SAIDA Project