Configuration properties, Functional blocks, Functional profiles – Echelon OpenLNS Commissioning Tool User Manual

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OpenLNS CT User’s Guide

7

The application program in a device does not need to know where input network variable values come
from or where output network variable values go. When the application program has a changed value
for an output network variable, it simply assigns the new value to the output network variable.

Through a process called binding that takes place during network design and installation, the device is
configured to know the logical address of the other device or group of devices in the network
expecting that network variable’s values. The device’s embedded firmware assembles and sends the
appropriate packet(s) to these destinations. Similarly, when the device receives an updated value for
an input network variable required by its application program, its firmware passes the data to the
application program. The binding process thus creates logical connections between an output network
variable in one device and an input network variable in another device or group of devices.

Connections may be thought of as virtual wires. For example, the dimmer-switch device in the
dimmer-switch-light example could be replaced with an occupancy sensor, without making any
changes to the lighting device.

Configuration Properties

Configuration properties define how an application device behaves by determining the manner in
which data is manipulated and when it is transmitted. Configuration properties determine the functions
to be performed on the values stored in the network variables. For example, a configuration property
may specify a minimum change that must occur on a physical input to a device before the
corresponding output network variable is updated. Like network variables, configuration properties
have types that determine the type and format of the data they contain.

Functional Blocks

Applications in devices are divided into one or more functional blocks. A functional block is a
collection of network variables and configuration properties that work together to perform a single
task. These network variables and configuration properties are called the functional block members.
For example, a digital input device could have four digital input functional blocks that contain the
configuration properties and output network variable members for each of the four hardware digital
inputs on the device. A functional block is an implementation of a functional profile.

Functional Profiles

A functional profile defines mandatory and optional network variable and configuration property
members for a type of functional block. For example, the standard functional profile for a light

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