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TransNET OEM Integration Guide
05-3946A01, Rev. C
REPEAT [0–10]
Downstream Repeat Transmission Count
The
REPEAT
command affects “downstream” data. The command causes a
Master or Extension to always repeat transmissions for the specified number
of times (range is 0 to 10; default selection is 3). Unlike the
RETRY
command,
there is no acknowledgment that a message has been received.
Use the
REPEAT
command without a value to display the current setting.
RETRY [0–10]
Upstream Repeat Transmission Count
The
RETRY
command affects upstream data. The command selects, or
displays, the maximum number of times (0 to 10) that a Remote radio will
re-transmit data. The default setting is 10.
This command is associated with ARQ (Automatic Repeat Request) opera-
tion of the radio and is intended for use in areas with heavy radio interference.
When the
RETRY
command is issued without parameters, the maximum
retransmission count is shown. A value of 0 represents no retries, while
values of 1 or greater successively improve the chance of data delivery in
spectrally harsh environments (at the expense of possibly increased latency).
The
RETRY
value is only setable at the Master. It is readable by a synchro-
nized Remote.
RSSI
Received Signal Strength Indicator
This command displays the radio’s Received Signal Strength Indication in
dBm (decibels relative to 1 mW). The output can range from –40 dBm to
–120 dBm. Command availability and results depend on the mode of opera-
tion (Master or Remote). The closer to 0 dBm, the stronger the signal, thus a
reading of –70 dBm is stronger than –80 dBm.
For a Remote radio, under normal operation, RSSI is based on the average
signal strength of the SYNC message received in each of the eight frequency
zones. (RSSI is sampled each time a SYNC message is received.) When using
the RSSI reading to align a directional antenna, it is important to make
changes slowly so that the RSSI reading will provide meaningful results. It
will take several seconds to indicate a change in signal level. The radio stays
in RSSI mode until
is pressed.
For a Master radio, under normal operation, entering the RSSI command
causes the response
NOT AVAILABLE
to be returned. This is because a Master
is normally receiving signals from several Remote stations and an RSSI
reading would be continually changing. The only exception is when the
SETUP
command has been asserted. This disables hopping and allows reading
a “raw” RSSI signal level in real time from a Master or Remote radio.
NOTE 1:
RSSI readings will not accurately indicate signals stronger than –40 dBm.
NOTE 2:
RSSI works for Dependent Masters. Command displays “NOT AVAILABLE” if the
Dependent Master is not synchronized.
ENTER
