Echelon LNS - Manual (Page 214)

LNS Programmer's Guide 200
Setting Monitoring Options
Each
MonitorSet
object, and each individual
MsgMonitorPoint
and
NvMonitorPoint
object, contains properties that allow you to determine the behavior of the monitor set or
monitor point while it is monitored and controlled. These properties are listed and
described in the following sections.
•
MonitorSet.NvOptions
and
MonitorSet.MsgOptions
– Each
MonitorSet
object contains an
NvOptions
property, and a
MsgOptions
property. The
NvOptions
property provides access to an
NvMonitorOptions
object that stores the default monitoring options
that are applied to all network variable monitor points as they are added
to the monitor set. The
MsgOptions
property provides access to a
MsgMonitorOptions
object that stores the default monitoring options
that are applied to all message monitor points as they are added to the
monitor set.
Changes to the
NvOptions
and
MsgOptions
properties are not managed
retroactively, meaning that monitor points that have already been added
to a monitor set are not affected when these properties are changed.
However, for network variable monitor points, there are a few exceptions
to this rule. See NvMonitorOptions Object on page 202 for more
information on this.
•
NvMonitorPoint.DefaultOptions
and
MsgMonitorPoint.DefaultOptions
– Each NvMonitorPoint and
MsgMonitorPoint object in a monitor set contains a DefaultOptions
property. The
DefaultOptions
property provides access to a
MsgMonitorOptions
object (or
NvMonitorOptions
object) that stores
the default monitoring options that are applied to that particular monitor
point. These are the options that will be used for that monitor point when
the monitor set is opened, and a monitoring session begins.
When a monitor point is added to a monitor set, the
DefaultOptions
for the
point are set to match to the settings stored in the
NvOptions
or
MsgOptions
objects for the monitor set. You can modify the monitor point’s
DefaultOptions
property if you want that monitor point to have different
default options than the rest of the set. However, if you change these
properties while the monitor set is open, the changes will not be reflected
until the monitor set is closed and re-opened.
NOTE: Because temporary monitor points are only used in a single client
session, their
DefaultOptions
are not accessible. If you attempt to acquire
the DefaultOptions property through a temporary monitor point, the
LCA:#161 lcaErrNotAllowedOnTemporaryObject exception will be
thrown. All temporary monitor points are created with the default options
defined for the monitor set via the NvOptions and MsgOptions properties.
•
NvMonitorPoint.CurrentOptions
and
MsgMonitorPoint.CurrentOptions
– Each NvMonitorPoint and
MsgMonitorPoint object in a monitor set contains a CurrentOptions
property. The
CurrentOptions
property provides access to a
NvMonitorOptions
object (or
MsgMonitorOptions
object). The
CurrentOptions are set to match the values of the monitor point’s
DefaultOptions
object every time the monitor point is enabled.