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4 using the read function on the data server, Using the read function on the data server -11, Using the read function on the data server – Echelon i.LON SmartServer 2.0 User Manual

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i.LON SmartServer 2.0 Programmer’s Reference

4-11

or more elements. Each element includes a property that specifies a
unique data point to be created or modified.

Each element may also include a series of properties that define the configuration of the new
(or modified) data point within the Data Server. This set of properties is the same, whether you are
creating a new data point or modifying an existing data point. The previous section, Using the Get
Function on the Data Server
, details the properties you can include in the Set function.

You can set multiple data points with a single Set message. However, you should not attempt to create
or write to more than 100 data points with a single call to the Set function. Additionally, to optimize
the memory available to the SmartServer, you should not have more than 1,000 data points in your
network at any time.

The following example demonstrates how to add a new SNVT_temp f [1] input data point to the data
server on the Net/LON/iLON App/VirtFB functional block.

Request



0

xsi:type="Dp_Cfg">

Net/LON/iLON

App/VirtFb/temp_f[1]

Dp_In
#0000000000000000[0].SNVT_temp_f#US

LonFormat="UCPTdirection">DIR_IN

1

LonFormat="#0000000000000000[0].SNVT_temp_f#US">72.5

field="">°F


0
OCCUPIED

LonFormat="#0000000000000000[0].SNVT_temp_f#US">69.8



1
UNOCCUPIED

LonFormat="#0000000000000000[0].SNVT_temp_f#US">60.8



2
STANDBY

LonFormat="#0000000000000000[0].SNVT_temp_f#US">66.2




Response



0


Net/LON/iLON

App/VirtFb/temp_f[1]



4.3.4

Using the Read Function on the Data Server

You can use the Read function to read the value and status of any data point that you have added to the
Data Server. The input parameters you supply to the function will include one or more
elements. Each element includes a property that specifies the data points whose
values and statuses are to be returned.

Alternatively, you can use an xSelect statement to return the values and statuses of a specific set of
data points on the Data Server. The filters you can use in an xSelect statement in the Read function