Data server, Data server -1, Chapter 5, data server – Echelon i.LON 100 e2 Internet Server User Manual

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LON 100 Internet Server Programmer’s Reference

5-1

5 Data Server

The

LON 100 uses the concept of a data point to map logical names to

LON 100 system

variables, network variables defined on the

LON 100 LonTalk interface, and explicitly

addressed network variables. This paradigm can be extended to handle data from other types

of control networks as drivers for these buses become available.
Data points provide the

LON 100 applications and Web server with a generic, open way to

handle any piece of information in any type of network, such as the current value of a

network variable in an LNS-managed network, or an explicit message in a closed L

ORKS

system. This document describes how to use two kinds of data points:

• NVL data points for network variables that are local to the

LON 100

• NVC data points for

LON 100 system variables that maintain constant values

The

LON 100 Data Server handles all the details of these data point that are required by

the various applications of the

LON 100, such as how often a data point should be polled, its

default value, its heartbeat, its current status, and its current value.
At the DataServer layer, all data points have the same set of properties, regardless of the

network or device each data point is local to. This is made possible by the drivers that exist
for each data point type, which handle communication between the Data Server and the

network each data point is local to.
Use a standard network management tool for the particular data point type to configure each
driver on the

LON 100. For example, you could use an LNS-based network management

tool to configure the NVL points on the

LON 100. This layer of abstraction between the

drivers and the DataServer provides a mechanism for all

LON 100 applications to use data

points of all types in the same way.

The Data Server also ensures that the configuration, status and value of each data point

recognized by the tools you can use to configure the

LON 100 remain synchronized with

each other, and within the device each data point is local to. The tools you can use to
configure the

LON 100 include include custom SOAP applications, L

AKER

, and the

LON 100 Configuration Software. The following diagram shows the relationship between

the

LON 100 Data Server and the different tools you can use to configure the

LON 100

and its applications.