Echelon LNS DDE Server - Manual (Page 54)

If you are communicating as a Lightweight client over an LNS/IP Channel (see
Remote Settings, earlier in this Chapter), this option will not be available.
Network Event Subscription
This setting controls how the LNS DDE Server subscribes to network variable
address and connection change events. This can be set to one of the following:
None
The LNS DDE Server subscribes to no change events.
If event subscription is disabled, LNS DDE Server startup is faster as
no change events are subscribed to. This speed gain is made at the
expense of possible data loss for the monitoring client if a network
variable’s binding changes. LNS Server overhead is reduced
compared to the default, as no change notifications are sent to the
monitoring client. Use this value if you have a static network. If this
option is selected, you cannot use bound updates to monitor output
network variables on the network.
Monitored The LNS DDE Server subscribes to individual network variable
change events.
If individual event subscription is enabled, LNS DDE Server startup
may be slow because a separate change event is subscribed to for each
monitored network variable. The LNS Server’s overhead is
minimized, as change notifications are only sent for monitored
network variables. The monitoring client should never lose data due
to binding changes. Use this value for a dynamic network where
devices and connections are frequently changed.
All The LNS DDE Server subscribes to a single generic network variable
change event. This is the default value.
If generic event subscription is enabled, then the LNS DDE Server
startup is faster as only one event subscription takes place. However,
the LNS Server's overhead will increase when changes are made to
the network due to the extra event notifications that are sent for
every connection change. Use this value for a mainly static network.
Default Data Reporting Settings
Polling Interval (1/10 sec)
This setting specifies the default polling interval that the LNS DDE Server will use
when polling unbound network variables, or the minimum update interval for bound
network variables. Specify a value in tenths of a second. For example, a value of 5
specifies that the LNS DDE Server will poll every 0.5 seconds. When network
variables are bound to the server, this setting specifies the minimum update rate
between the LNS DDE Server and the DDE client. The poll interval may be between
1 and 32000 (.1 seconds and 53 minutes, 20 seconds). The default polling interval is
10 (1 second).
3-22 Using the LNS DDE Server