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a DiscoverReply with its system address. After joining one of the system networks, all routers and re-
motes periodically transmit heartbeat status messages that contains their MAC address, network address,
network ID and other information. Note that the address of any radio can be constructed as follows:
0xFF + NwkID + NwkAddr.
2.12.4 Tree-Routing System Implementation Options
There are three ways to assign parent network IDs and system addresses to the routers and remotes in a
tree-routing system - dynamic router parent and remote system address assignment, manual router
parent assignment with dynamic remote address assignment, and manual router parent and remote
address assignment.
Dynamic router parent and remote address assignment is the preferred method for most systems that
contain just a few routers. This assignment method provides several advantages. The router parent and
remote system addresses do not have to be pre-assigned, reducing initial system planning details. In
case of a parent failure, child devices will automatically attempt to join another parent. Once the system
becomes organized, heartbeat status messages and/or Discover commands can be used to log the
system addresses against the MAC addresses of each router and remote in the system.
Manual router parent assignment with dynamic remote address assignment is the preferred method for
most systems with a large number of routers. Manual router parent assignment avoids the possibility of
the system creating a long chain of parent router-child router links which would introduce unnecessary
message latency. However, manual router assignment precludes a child router from attempting to link
with another parent in case its parent router fails. The parent address of each router is known before the
system becomes organized, and heartbeat status messages and/or Discover commands can be used to
log the system addresses against the MAC addresses of each remote in the system.
Manual router parent and remote address assignment allows all radios addressing to be preplanned and
preset before a system is installed. Manual system addressing precludes child radios from attempting to
re-link to the system by joining another parent if the assigned parent fails, but simplifies application code
development by removing the need to dynamically update a database that matches system addresses to
MAC addresses for each router and remote. The task of manually assigning system addresses to all
routers and remotes in a tree-routing system can be somewhat tedious. Contact RFM’s module technical
support group for the latest support tools for manual address assignment. Table 2.12.4.1 summarizes
radio parameter settings for each assignment method.
Dynamic Router Parent Assignment and Dynamic Remote System Address Assignment
Radio InitialParentNwkID
StaticNetAddress
BaseModeNetID
Router
0xFF (join any parent)
0xFF (assigned by parent)
0x01 - 0x3F (router NwkID)
Remote
0xFF (join any parent)
0xFF(assigned by parent)
0xFF (not used by remote)
Manual Router Parent Address Assignment with Dynamic Remote System Address Assignment
Radio InitialParentNwkID
StaticNetAddress
BaseModeNetID
Router
0x00 - 0x3F (specifies parent)
0xFF (assigned by parent)
0x01 - 0x3F (router NwkID)
Remote
0xFF (join any parent)
0xFF(assigned by parent)
0xFF (not used by remote)
Manual Router Parent and Remote System Address Assignment
Radio InitialParentNwkID
StaticNetAddress
BaseModeNetID
Router
0x00 - 0x3F (specifies parent)
0x01 - 0x7E (sent to parent)
0x01 - 0x3F (router NwkID)
Remote
0x00 - 0x3F (specifies parent)
0x01 - 0x07 (sent to parent)
0xFF (not used by remote)
Table 2.12.4.1