Company Confidential
33
Raveon Technologies Corp.
transmitted twice, once by the originating RF-7800W and once by the
repeater.
Step 4.
Determine TDMA slot time required to send the position. Slot times are
programmed with the
SLOTTIME
command, and are in 10mS
increments. Always add 10mS additional time for some margin. For
example, if your position transmission requires 65mS, then the correct
SLOTTIME
to program would be 80mS. The
SLOTTIME
must be
greater than the duration of the position transmission. If a repeater is
used with a 80mS position report, then the
SLOTTIME
should be set to
at least 160mS. Note, the SLOTTIME may be set longer than required
to transmit a position, it just may not be shorter. If Encryption is
enabled (which it is by default), the slot time must be 20mS longer to
account for the encryption/decryption processing.
Over-the-air rate
Number of
Modulation
Levels
Position
/Status
Transmissio
n Duration
Suggest TDMA Slot time
4800bps
(R2=3)
Default setting
2
70mS
100mS
9600bps
(R2=5)
2
45mS
50mS (No Encryption)
70mS (if encryption enabled)
5142bps
(R2=7
)
2
65mS
100mS
Step 5.
Program the
TDMATIME.
The TDMA time must be greater than the
maximum number of vehicles the system will ever need to support,
times the SLOTTIME.
# of vehicles X _SLOTTIME_ = TDMATIME
For example, if you will have up to 85 vehicles, and the SLOTTIME is
200mS, then the TDMATIME must be at least 17.4 seconds so a value
of 20seconds for the TDMA time is appropriate.
10.4. Debug Related Commands
Bench Testing
(Must be in command mode to test. Enter SETPORT [[[+++]]] at the keyboard to put unit into config/test
mode.)
ATTD x
Various transmit test routines.
0 = Go back to normal mode. Stops the test.
1 = Random data transmit.
2 = Hop up/down one channel
3 = Force PLL to fast lock mode
4 = Transmit all 0s
5 = Transmit all 1s
6 = Enable the test points on the PCB.
