Echelon FTXL - Manual (Page 36)

24 Creating a Model File
Model File Overview
The interoperable application interface of a L ON W ORKS device consists of its
functional blocks, network variables, configuration properties, and their
relationships. The
network variables are the device’s means of sending and
receiving data using interoperable data types. The configuration properties are
the device’s means of providing externally exposed configuration data, again
using interoperable data types. The configuration data items can be read (and
typically also written) by a network tool. The device interface is organized into
functional blocks , each of which groups together a collection of network variables
and configuration properties that are used to perform one task. These network
variables and configuration properties are called the functional block members .
The model file describes the functional blocks, network variables, configuration
properties, and their relationships, that make up the interoperable interface for
an FTXL device, using the Neuron C programming language. Neuron C is based
on ANSI C, and is designed for creating a device’s interoperable interface and
implementing its algorithms to run on Neuron Chips and Smart Transceivers.
However, you do not need to be proficient in Neuron C to create a model file for
an FTXL application because the model file does not include executable code. All
tools required to process model files are included with FTXL; you do not need to
license another Neuron C development tool to work with an FTXL model file.
The model file uses Neuron C Version 2.1 declaration syntax.
The LonTalk Interface Developer utility uses the model file to generate device
interface data and device interface files. You can use any of the following
methods to create a model file:
• Manually create a model file
A model file is a text file that you can create with any text or
programming editor, including Windows Notepad. Model files have the
.nc file extension. This chapter describes the types of Neuron C
statements you can include in a model file. Appendix C describes the
syntax for the Neuron C statements.
• Reuse existing Neuron C code
You can reuse an existing Neuron C application that was originally
written for a Neuron Chip or a Smart Transceiver as a model file. The
LonTalk Interface Developer utility uses only the device interface
declarations from a Neuron C application program, and ignores all other
code. You might have to delete some code from an existing Neuron C
application program, or exclude this code using conditional compilation,
as described later in this chapter.
• Automatically generate a model file
You can use the NodeBuilder Code Wizard, included with Release 3 or
later of the NodeBuilder Development Tool, to automatically generate a
model file. Using the NodeBuilder Code Wizard, you can define your
device interface by dragging functional profiles and type definitions from
a graphical view of your resource catalog to a graphical view of your
device interface, and refine them using a convenient graphical user
interface. When you complete the device interface definition, click the
Generate Code and Exit button to automatically generate your model file.
Use the main file produced by the NodeBuilder Code Wizard as your
model file. NodeBuilder software is not included with the FTXL