Cirronet HopNet 10 Series, User Manual

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Network Commands
800281 Rev. B HopNet Family of Products 63
Enable Global Network Mode
For networks with multiple base stations, remotes are ordinarily only able to link
to one base station, set by the hopping pattern. Mode 1 enables the global mode
that allows remotes to link to any base station they can hear, acquiring whatever
hop pattern is required. In this mode a remote can only change base stations once
it is no longer registered with a base station. Mode 2 enables seamless roaming
where a remote will seamlessly register with a new base station based on
received signal strength before it has lost registration with the old base station.
To implement seamless roaming without the potential for data loss,
synchronization between base stations is required. This feature is available in the
SNAP2410 family of products only. Bases and remotes must be set to the same
mode.
Set Hopping Pattern
The HopNet has 64 preprogrammed hopping patterns (also referred to as
network numbers). By using different hopping patterns, nearby or co-located
networks can avoid interfering with each other’s transmissions. Even if both
networks tried to use the same frequency, on the next hop they would be on
different frequencies.
Set Transmit Power
The HopNet has two preset transmit power levels, 10mW (10dBm) and 100mW
(20dBm). Control of the transmit power is provided through this command.
Default is 100mW.
Read Receive Signal Strength Indicator (RSSI)
This command reports the relative signal strength averaged over the last 10 hops.
This command returns a one byte value that is proportional to received signal
strength and can range from
00H
to
FFH
. Typical values range from
30H
to
80H
where the lower the number the lower the received signal strength and the
higher the number the higher the received signal strength. This is a relative
indication and does not directly correspond to a field strength number. This is
available only at the remotes as the base station is the only source that transmits
on a regular basis. Plus, in a point-to-multipoint network the base will receive
different signal strengths from each remote.