Specifying a configuration property, Specifying a configuration property topic, Specifying a configuration property item – Echelon LNS DDE Server User Manual

Page 88: 2 reading and writing configuration properties

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Specifying a Configuration Property

Configuration properties may be associated with a device, L

ON

M

ARK

object, or

network variable. For example, a configuration property associated with a L

ON

M

ARK

object for a sensor may define the processing for the sensor data; a configuration

property associated with an output network variable may specify the override value

for the network variable. To access a configuration property, you must select the
type of configuration property in the DDE Topic, and the specific configuration

property in the DDE Item.

Specifying a Configuration Property Topic

The LNS DDE Server uses the configuration property topics to send and receive
information about configuration properties. There are four configuration property

topics: DevCP; DevNVCP; LMCP; and LMNVCP. Within the configuration

property topic, the LNS DDE Server requires 2-4 pieces of information to be able to
identify a configuration property. How much information it needs depends on what

type of configuration property topic it is.


A configuration property topic is specified using the standard topic format or custom

topic format described in Chapter 4. The topic type will be one of the following

configuration property topics:

Category Topic

Type

Description

Configuration
Property

DevCP

Configuration properties for a device.

LMCP

Configuration properties for a L

ON

M

ARK

object.

LMNVCP

Configuration properties for a network variable
member of a L

ON

M

ARK

object.

DevNVCP

Configuration properties for a network variable on a
device. This type accesses configuration properties for

network variables on a device that are not members of
a L

ON

M

ARK

object.

NVCP

Configuration properties for a network variable. As
with the NV topic type, any network variable may be

specified. The network variable name may be

ambiguous when specified using this topic type.

Specifying a Configuration Property Item

A configuration property item identifies a device and a configuration property or

configuration property field on the device.


The format for specifying this information is the following:

device_name[.lm_name][.nv_name[[array_index]]].cp_name[.field_n
ame] [parameters]

6-2

Reading and Writing Configuration Properties

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