Echelon LNS - Manual (Page 252)

LNS Programmer's Guide 238
Value Description
lcaDataSourceOptionsTypeDefaultValue If you use this option to create a
DataPoint
, or if
you set the
SourceOptions
property of the
DataPoint
object to this value later, then the
DataPoint
will always return the default value of
configuration properties using the same type as
the source configuration property. The default
value is generally read from the functional profile
template on the device containing the
configuration property, or from the type definition
for this configuration property type. Data points
created with this option set are read-only.
Note that this value represents the “type default”
defined in the type resource file. The default value
of a given configuration property may differ from
the default value of its type, since the default
configuration property values for a given template
are defined in the external interface file and can
be set from the current values in the device.
When you create a
DataPoint
object with the
lcaSourceDataOptionNormal
option
described in Table 9.4, LNS will update the value stored in the database for the source
ConfigProperty
object and schedule an update to the physical device each time you
update the value of the
DataPoint
object. This keeps the values stored in the LNS
database and the physical device on the network in synchronization, and is the
recommended way to update configuration property values.
However, in some cases, the values of the configuration properties in the LNS database
may become out-of-sync with the values of the configuration properties stored in the
devices on your network. The next section describes how you can resolve these situations.
Resynchronizing Configuration Property Values
Assuming you know when the configuration properties on a device in your network are
updated, and the LNS database is not updated as well, you can use the
UploadConfigProperties()
and
DownloadConfigProperties()
methods to
resynchronize the values stored in the LNS database with the new values of the
configuration properties in the device (and vice versa). This is described in Downloading
and Uploading Configuration Properties on page 126.