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Set the speed that the master radio will use to transmit.
Set the speeds that the remote radios may use to transmit.
Since transmissions from the master radio must be received by all remotes in the
network irrespective of distance or RF conditions, the master radio is limited to a single
data-rate that is selected in the
Master Transmit Mode
drop-down box. Remote radios
must also be configured with the data-rate the master will use to communicate.
Remote radios in a MSMP network independently and dynamically select the optimal
data-rate. The list of data-rates is selected by checking the corresponding check-boxes
on the remote radio. Data-rates which remote radios may use to communicate must
also be defined on the master radio. Thus the configuration should match between the
master radio and each of the remote radios.
Note that the master radio does not need to have downstream radios defined since
there will be multiple downstream radios. However, each remote radio must have the
upstream radio identified as the master radio.
Multi-Master Sync
On the right side of the dialog are the parameters for the MMS (Multi-master sync).
This function allows multiple master radios to synchronize their transmit and receive
times so that all radios transmit at the same time reducing noise and interference during
the receive process. If the radios are set up with the same modulation and packet sizes
then the transmit, receive and slot timings are all the same. The synchronization
between radios is performed by a one pulse-per-second signal applied to the I/O
connector on the side of the radio. The first pin towards the front is the ground and
second pin is the electrical input which requires a 5V square wave 1 Hz waveform. The
duty cycle is not critical and should be between 10% and 90%.
The “
MMS
” may operate in one of two modes; “
External
” input (slaved) or internally
“
Generate
” (master) the 1Hz signal for other slaves. If an external pulse generator is
used (such as from a GPS receiver), than all radios would be set to External.
Additionally, the “
MMS Hop Offset
” may be set so that each of the radios operate at a
different location in the hop table. For example, if there are 6 frequencies in the hop
table, then setting the first radio to “0” and the second radio to “3” results in the radios
transmitting at frequencies 0 and 3 for the first slot, then frequencies 1 and 4 for the
second slot, 2 and 5 for the third slot, 3 and 6 for the fourth slot, 4 and 1 for the fifth
slot and so on. This permits frequency separation between the radios.
Note that the remote radios will be monitoring all of the RF transmits but will only
synchronize when the network address and the master device ID match. Thus, each
master radio on a MMS system must have a unique network address,
