Echelon i.LON 100 e2 Internet Server User Manual
Page 58
LON 100 Internet Server Programmer’s Reference
Property Description
The format description of the data point. This determines many
factors about the data point, including the type of values it
takes, and its base type. This could be any standard (SNVT)
format type included in the
i.
LON 100 resource files, or any
user-defined (UNVT) format type included in resource files
uploaded to the
i.
LON 100. For more information on the
i.
LON
100 resource files, see i.LON 100 Resource Files on page 4-8.
The SNVT format types included in the
i.
LON 100 resource files
are also listed and described in the SNVT Master List, which
can be downloaded as a PDF by selecting the Documentation
link on Echelon’s Support Web site:
Unit text. This property is a string up to 228 characters long
that describes the units the value of a data point is measured in.
It should be filled in based on the network variable type
assigned to the data point.
A default value will be assigned to this property, if a unit for the
network variable type chosen for the data point exists in the
i.
LON 100 resource files.
This read-only property is assigned to the data point
automatically, and is based on the point’s
point, as defined in the base_type_t enumeration in the
BAS_Controller resource files for the
i.
LON 100.
Read-only. The size of the data point. This is determined based
on the
This property applies to output data points. It defines the
maximum amount of time that may elapse before the data point
is updated on the network, if it is set to a non-zero value.
For example, if a SNVT_temp value data point is changing by
one degree every 10 seconds and this property is set to two
seconds, the
i.
LON 100 will update the value of the data point
on the network every two seconds, even though the value of the
data point is not changing more than once every 10 seconds. The
receiver can use this output as a heartbeat. The receiver will
know something is wrong if he or she does not receive an update
every two seconds.