Spread Spectrum Wireless Data Transceiver User Manual
(6)
N
ET
W
ORK
ID
NetWork ID allows MultiPoint networks to be established without using the Call Book. NetWork ID’s
default setting is 255. This setting disables NetWork ID and enables Call Book. To enable NetWork ID
this must be set to a value between 1 and 4095, except 255. Since NetWork ID does not use serial
numbers, MultiPoint Masters and Repeaters may be replaced without reprogramming all of the Slaves in
the network. Slaves will link with the first Master or Repeater that it hears that has a matching NetWork
ID.
Additionally, this allows a Slave to establish communications with different Masters, though not at the
same time, without having the serial numbers in the Call Book. This is very useful in mobile MultiPoint
applications.
(8)
M
ULTI
M
ASTER
S
YNCH
MultiMaster Synch is reserved for applications, either Point-to-Point or MultiPoint, with concentrations of
Master units where it is necessary to reduce interference between the Masters. Please contact FreeWave
Technologies for more information.
(9)
1
PPS
E
NABLE
/D
ELAY
The 1 PPS Enable/Delay option allows the radio network to propagate a GPS 1PPS signal from the
Master transceiver to all Slaves in a MultiPoint network. When this parameter is properly enabled a 1 PPS
pulse on the DTR pin of the Master will provide a 1 PPS pulse on the CD line of any Slave in the network.
To use the 1 PPS Enable/Delay feature the steps outlined below must be followed:
1.
The 1 PPS Enable/Delay parameter in the Master must be set to 0.
2.
The Master must have a 1 PPS pulse on the DTR pin.
3.
The 1 PPS Enable/Delay parameter on the Slaves must be enabled. The calibration on the Slave
is typically factory set. However, the Slaves may also be calibrated with the following procedures:
4.
Trigger an oscilloscope on the 1 PPS pulse (from a GPS receiver) on the DTR pin of the Master.
5.
Monitor the CD line of the Slave.
6.
If the timing on the Slave differs from the Master it may be adjusted via the value in the Slave's 1
PPS Enable/Delay parameter. The difference in time between each incremental integer value is
542.534nS. Changing the parameter to higher values decreases the Slave time delay and
changing the parameter to lower values increases the time delay.
When properly calibrated the CD line of a Slave radio will output a pulse that goes high for about 2 mS in
synch with the 1 PPS pulse on the Master radio. The output on the Slave will occur within 20
microseconds of the input to the Master.
Note:
When 1 PPS is enabled, the Master
must
have a 1 PPS pulse on its DTR pin, otherwise the RF
network will not function.
(A)
S
LAVE
/R
EPEATER
The Slave/Repeater mode allows a transceiver in a MultiPoint system to switch between Slave and Repeater
functions. When in this mode, a transceiver will repeat any packets sent across the network, as well as send
them out its RS232 port. Thus, where one transceiver to repeat and one to be a Slave would have been
previously needed, now only one is needed with this setting. To operate a transceiver as a MultiPoint
Slave/Repeater, the operation mode must be set to (7) MultiPoint Repeater and the Slave/Repeater setting
changed to 1.
LUM0002AD Version
6.1
44
