Echelon NodeBuilder FX - Manual (Page 30)

16 Introduction
for network variable values. Neuron C provides an easy-to-use programming model familiar to any C
language programmer that encapsulates the complexity of distributed applications.
Configuration Properties
L ON W ORKS applications may also contain configuration properties. Configuration properties allow
the device’s behavior to be customized using a network management tool such as the LonMaker tool or
a customized plug-in created for the device (see the LNS Plug-in Programmer’s Guide for more
information on creating LNS device plug-ins).
For example, an application may allow an arithmetic function (add, subtract, multiply, or divide) to be
performed on two values received from two network variables. The function to be performed could be
determined by a configuration property. Another example of a configuration property is a heartbeat
that determines how often a device transmits network variable updates over the network.
Like network variables, configuration properties have types that determine the type and format of the
data they contain.
The NodeBuilder Code Wizard automatically generates the required configuration property
declarations for your device’s interface and most of the required infrastructure code in your device’s
Neuron C application. The NodeBuilder tool supports configuration properties with an easy-to-use
programming model in Neuron C.
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, which are used together to perform one
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.
The NodeBuilder Code Wizard automatically generates the required functional block declarations for
your device’s interface in your device’s Neuron C application.
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
actuator has mandatory SNVT_switch input and output network variables, optional
SNVT_elapsed_tm and SNVT_elec_kwh output network variables, and a number of optional
configuration properties. The following diagram illustrates the components of the standard light
actuator functional profile: