Scope selectors – Echelon LNS User Manual
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LNS Programmer's Guide
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between different measurement systems, to provide alternate industry-specific
measurement units, or to provide locale-specific formatting for times, dates, or numeric
value separator characters.
A LonMark Functional Block groups network variables and configuration properties that
are related to a particular function of the device. LonMark Functional Blocks make a
device easier to install and configure. Each LonMark Functional Block is defined by a
functional profile that defines the network variables and configuration properties that
comprise the class of functional blocks. For example, a digital input device with four
switches could contain one LonMark Functional Block for each switch. For general
information on LonMark Functional Blocks, consult the LonMark Application-Layer
Interoperability Guidelines, which can be downloaded from LonMark website at
Functional profiles, network variable types, and configuration property types are defined
in device resource files, which are grouped into resource file sets. A complete resource file
set consists of a type file (.TYP extension), a functional profile definitions file (.FPT
extension), a format file (.FMT extension), and one or more language files (.ENG, .ENU
or other extensions).
You can create resource files with the Echelon NodeBuilder Resource Editor tool, which
The LonMark Interoperability Association also provides a standard resource file set,
containing the most commonly used standard network variable types (SNVT),
configuration property types (SCPT) and functional profiles (SFPT). The most recent
standard resource file set is included with the LNS Server installation for Turbo Edition.
The device manufacturer typically provides all device resource files that are referred to
by the device (with the exception of the standard resource file set).
Each resource file set must be registered with the resource catalog. The catalog is a
repository of all resource file sets available on a given machine. Resource file sets must
be registered with the catalog that belongs to the LNS Server PC, and will typically need
to be registered on each PC running an LNS client application, unless it is a Lightweight
client application. The resource catalog is a file that is typically named LDRF.CAT, and
is located in the [Windows Drive]\LonWorks\Types folder by default.
The device plug-in software that ships with most LNS devices will typically install the
device resource files into an appropriate location and perform the registration with the
resource catalog at installation time. For manual registration, you can use the
LDRFCAT.EXE utility’s graphical user interface.
Scope Selectors
Each set of resource files must be associated with a particular program ID, a range of
program IDs, or with all program IDs to associate it with a network variable,
configuration property, or
LonMarkObject
on a device. The type of association is called
the scope of the resource file, and the scope is specified using a scope selector. The scope
selector for a resource file specifies what part or parts of a device’s program ID should be
used when selecting the resource file. The various scope selectors you can use with LNS
are described below.