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The
auto
setting will cause a remote to try all four over-the-air rates when scanning for a network to join.
Setting the
RF_DataRate
to a fixed value on the remotes will allow a network to link much faster than
using the
auto
setting. However, if the base
RF_DataRate
is changed when the remotes are set to a fixed
rate, the network will not link. Note that changing this setting does not take effect immediately. It must be
followed by a
MemorySave
command (See Section 4.2.9) and then a hardware reset.
HopDuration
- this sets the duration of the hop frame. The duration is set as a 12-bit value,
0.05 ms/count. Changing the hop duration must be followed by a
MemorySave
command to allow the
change to persist through a reset or power cycle. A
HopDuration
change takes effect immediately. Re-
motes will re-link following a
HopDuration
parameter change.
InitialParentNwkID
- this parameter selects the network ID that a base will use to start a network, or a
remote will be allowed to join. A value of 0xFF instructs a remote to operate in ’promiscuous mode’ and
join any network it finds (if set for a base, this will select the default network ID of 0x00.)
In a tree-routing system, this parameter controls which parent a child router or remote can join. Setting
this value to 0x00 forces a router or a remote to join with only the base. Setting this parameter to the
NwkID
of a parent router forces a child router or a remote to join only this parent’s network. Setting this
parameter to 0xFF in a router or remote allows them to join with any parent. In a tree-routing system, the
InitialParentNwkID
parameter also determines the hopping pattern for the parent and children of each
network. When a network ID equals or exceeds the number of unique hopping patterns, the hopping
pattern selection will “wrap around” to the network ID modulo of the number of hopping patterns. To
prevent interference between networks in a tree-routing system, networks with the same hopping pattern
must be physically separated by enough distance that they cannot receive transmissions from each other.
It is often convenient to set the
InitialParentNwkID
parameter value on remotes to 0xFF to allow them to
connect to any parent device. However, setting the
InitialParentNwkID
parameter value to 0xFF on a
system with a large number of routers can be problematical. This could result in very long routing paths,
slowing communications, and possibly causing reply delays to exceed the
P2PReplyTimeout
parameter
setting. For this reason, it is often best to design a tree-routing system using a large number of routers so
that each router has an explicit
InitialParentNwkID
.
SecurityKey
- this sets the 128-bit AES encryption key to be used. To protect the key, this is a write-only
parameter for the user (always reads back as 0x2A). Refer to the Section 2.16 for further information.
SleepMode
- this parameter enables sleep mode, which may be used in conjunction with the automatic
I/O reporting feature to wake up on specified triggers. Sleep mode is only available for remotes, and the
channel access mode for the network must be one of the CSMA modes. The default value for this param-
eter is 0 (off). Setting this parameter to 1 invokes sleep mode immediately. Setting this parameter to 2
invokes sleep mode following reset, allowing this and other parameter updates to be stored before sleep
mode is invoked.
WakeResponseTime
- this parameter sets the length of time that a remote in sleep mode will wait for a
response after sending an I/O report before going back to sleep, from a minimum of 10 ms to a maximum
of 2.5 seconds in 10 ms units. This time interval is set to allow the base host application to respond to a
remote with a packet before the remote returns to sleep. If this parameter is set to 0, the remote will stay
awake indefinitely after sending an I/O report. This allows the application as much time as needs for any
initial configuration after which it can cause the remote to re-enter sleep by setting this to the operating
value. The default value for this parameter is 50 ms.
