M7 GX Technical Manual
50
Raveon Technologies Corp.
by this unit. It will not repeat messages from
D, E, F, G,
or
H
because their Unit
IDs are not in the
Repeat Source
repeater table.
The second command above sets the Repeat Source to 1000 and the Repeat
Destination to 1000, both with a Mask of FFFF. The FFFF mask means all digits of
the source and destination are used to determine if the transmission should be
repeated. All packets from units with MYID 1000 (
A
)sent 1000 will be repeated by
this unit. In other words, all transmissions from
A
will be repeated by
B
.
To view the Repeater Table, use the
ATX
command, with no parameter. To view a
single entry in the table, use the
ATXn
, where n=1, 2, 3, or 4.
A repeater will not repeat a transmission if it originated the transmission. If another
M7 in the system has the same ID as the repeater, the repeater will not repeat data
from that particular unit.
The repeater’s ID must be unique in the system.
To delete an entry in the table so it has no effect on the operation, set the fields to
0. For example, to disable make entry 1, use the
ATX1 0 0 0 0
command.
10.3.
Setting the Over-The-Air Data Rate
The M7 has programmable over-the-air baud rates. The over-the-air rate is stored
in register R2, and is programmed with the
ATR2 x
command, where
x
is a number
corresponding to the rate. The are many possible baud rates, but not all rates
may be used with all radio modem models. Consult the following table.
Over-the-air rate
Radio
Bandwidth
Number of
Modulatio
n Levels
Position
/Status
Transmission
Duration
RV-M7 Modem Models that
support the rates
4800bps
(R2=3)
Default setting
12.5kHz or
25kHz
2
70mS
RV-M7-UC, RV-M7-UC-W
8000bps
(R2=4)
12.5kHz or
25kHz
4
50mS
RV-M7-UC, RV-M7-UC-W
9600bps
(R2=5)
25kHz
2
45mS
RV-M7-UC-W only
14400bps
(R2=10)
25kHz
4
30mS
RV-M7-UC-W
5142bps
(R2=7
)
12.5kHz or
25kHz
2
65mS
RV-M7-UC-N, RV-M7-UC-W
9600bps
(R2=8)
12.5kHz or
25kHz
4
45mS
RV-M7-UC-N, RV-M7-UC-W
Changing the over-the-air data rate will change the sensitivity of the receiver.
Higher-data rates require a stronger signal at the receiver to be properly received,
and thus have shorter range. The default over-the-air data rate for
RV-M7
radio
modems is 4800 baud for narrow-band versions, and 9600 baud for wide-band
versions.
The maximum over-the-air baud-rate for a narrow-band radio (12.5kHz channel-
spacing) is 9600bps. Due to IF filter limitations, the
RV-M7
does not work as well at