L
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Router User’s Guide
7-7
Router Installation with the LonBuilder Developer's Workbench
Chapter 9 of the
LonBuilder User’s Guide
describes how to define and install routers in
a development network using the LonBuilder Network Manager. A prerequisite to
creating router target hardware and node specifications is the definition of the
channels that will be included in the network as defined under
Defining Channels
in
Chapter 10 of the
LonBuilder User's Guide
. Routers are initially delivered
programmed with communications parameters listed in Appendix C. These values
should be used in the
Std Xcvr Type
field when defining channels with the possible
changes discussed next. Be sure to correctly set the minimum clock rate field. If this
field is set incorrectly, excessive collisions will occur. If a channel includes nodes with
a slower clock rate or less accurate clocks, the channel definition must meet this lowest
common denominator for optimal performance.
Additionally, if priority is configured for either channel, then the
Number of
Priority Slots
needs to be correctly set. If the
Average Packet Size
expected on
either channel is different than the standard transceiver type, optimal operation of
the collision avoidance algorithm requires that value to be changed also.
When defining the target hardware for the router specify
LONWORKS Router
for the
Router HW Type
field. The assignment of sides A and B to channel names is
arbitrary, and does not have to correspond to the Net 1 and Net 2 assignments on the
router. The LonBuilder Network Manager and the LonManager API will assign the
correct associations when the router is installed.
Set the
Packet Buffer
count and size fields to the count and size of the non-priority
output buffer queue as described under
Message Buffers
in Chapter 2.
Set the
Clock Rate
field to one of the following:
•
10MHz for side A of the RTR-10, and for L
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Router sides with TP/XF-
1250 transceivers;
•
5MHz for L
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Router sides with TP/FT-10, TP/XF-78, or TP/RS485
transceivers;
•
Match the B-side input clock for side B of the RTR-10. This will typically be
10MHz.
When installing the router, the channel definitions must match the transceivers on the
router, if they do not, the router could lose its ability to communicate. If either of the
channel definitions are modified from the standard transceiver types, then a
Yes
response is required to the prompt,
Do you want to install communications
parameters?
in order for those changes to be programmed in the router; otherwise
specify
No
.
WARNING: DO NOT use the
Yes
response to the prompt:
Do you want to
install communications parameters?
unless you have defined channels that
are compatible with the transceivers on the router.
When defining subnets for the router node specification, remember that a subnet may not
span two channels that are connected by intelligent routers. For a L
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network
containing two channels connected with an intelligent router, a minimum of two subnets
must be created, one for each channel. Each side of the router must belong to at least one