Echelon LNS User Manual

Page 164

LNS Programmer's Guide

150

Property Description

BroadcastOptions

This property determines whether LNS will use group or

broadcast addressing. You should note that when using

group addressing, there are 256 distinct groups per
network, and the group addresses consume address table

entries in both the receiving and transmitting devices

involved in the connection. Most application devices are
limited to 15 address table entries, and Network Service

Devices that use standard network interfaces are limited to
15 address table entries for use with group addressing.

Network Service Devices that use high performance

network interfaces support up to 256 address table entries.

Broadcast addressing cannot be used with the

acknowledged or request messaging services. In addition,
domain broadcasting cannot be used with the

unacknowledged/repeat messaging service. When LNS uses

broadcast addressing, it uses subnet broadcast if all
addressed devices are in the same subnet. Otherwise, it

uses domain broadcast addressing. You can set the service
type for a connection by writing to the ServiceType

property. Broadcasting with network variables applies only

to outputs.

Resources, includes a discussion of when and how you
should use broadcast addressing.

ReceiveTimer

RepeatTimer

TransmitTimer

The default values for these properties are determined

based on the network topology. Echelon recommends that
you do not change these properties from their default

values. If the default values for these properties are not

suitable for your application and you need to change them,
Echelon recommends that you use the Delay property of

each Channel object the connection is using to ensure that
each message is sent at the correct interval. The Delay

property allows your application to specify the number of

milliseconds expected to send a message and receive an
acknowledgment on the specified channel, so that

automatic timer calculations made by LNS can be affected

accordingly.

These properties accept a range of encoded values from 0 to

15. You can also write the value 254 to the property at any
time to restore it to the default. See the LNS Object Server

Reference help file for more information on these properties,
and for the actual values that correspond to each encoded

value.

RepeatCount

RetryCount

The default values for these properties are determined

based on the network topology. They each accept a range of
0-15.