New features, Propagating device changes while offnet, Dynamic functional blocks – Echelon LNS User Manual

Page 35: Datapoint object improvements

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LNS Programmer's Guide

21

Common exception codes for particular methods can and should be handled specially to

provide more guidance to your particular end-user. However, because the complete set of
exception codes that can be thrown for a given method can be large, and because all

exception codes must be handled by your application, you should also use a generic error

handler in your application that will handle all errors returned by LNS.

New Features

When adding new features to LNS, Echelon must make compatibility tradeoffs in order

to improve functionality and performance. Some of the new features described earlier in

this chapter may introduce compatibility issues into your application, so you should
consider the following information carefully when integrating these new features.

Propagating Device Changes While Offnet

The commission and replace operations behave identically in LNS Turbo Edition as in

prior versions of LNS, unless the new “propagate” flags provided with the

ReplaceEx()

and

CommissionEx()

methods are specified by the LNS application.

The new

AllowPropagateModeDuringRemoteOpen

property is simply an alias for the

RemoteIgnorePendingUpdate

property. The

RemoteIgnorePendingUpdate

property

is marked as hidden, but reading and writing the property is still supported by LNS

Turbo Edition.

Opening a remote Full client application with LNS Turbo Edition may succeed while the

system management mode is set

lcaMgmtModeDeferConfigUpdates

, even if there are

pending updates for other devices, and the

RemoteIgnorePendingUpdate

flag is

False

. The Network Service Device will be re-commissioned in this case. In prior

versions of LNS, the open would fail, and return an error.

Opening a remote Full client application with LNS Turbo Edition while the system

management mode is set to

lcaMgmtModeDeferConfigUpdates

, and the

AllowPropagateModeDuringRemoteOpen

property is set to

True,

may result in

commissioning the remote Network Service Device without propagating pending updates

to other devices. In prior versions of LNS, this would always result in propagating all
pending changes.

Dynamic Functional Blocks

Your application might currently assume that it will find all defined

LonMarkObject

objects for a device by accessing the

DeviceTemplate

object’s interface. However, the

dynamic

LonMarkObject

objects on a device do not appear in the interface of the

device’s

DeviceTemplate

object. Another possible problem is if your application

assumes that the collection index assigned to a LonMarkObject is one greater than the

value of the LonMarkObject object’s Index property. This relationship happens to hold
for static LonMarkObject objects, but may not for dynamic LonMarkObject objects.

DataPoint Object Improvements

The

DataPoint

object was introduced in LNS 3.0 to allow convenient access to the data

contained in monitor points. The feature allowing access to individual

DataPoint

fields

contained several defects that may not allow a current implementation of the feature to

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