User's Manual

Spread Spectrum Wireless Data Transceiver User Manual
LUM0002AF Rev D Version 6.3 45
Without having the serial numbers in the Call Book, a Slave may establish communications with different
Masters, though not at the same time. This is very useful in mobile MultiPoint applications.
(8)
MULTIMASTER SYNCH
MultiMaster Synch is reserved for applications, in both Point-to-Point and MultiPoint modes, 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 ENABLE/DELAY
The 1 PPS Enable/Delay option allows the radio network to propagate a 1PPS signal from the Master to
all Slaves in a MultiPoint network. When this parameter is enabled a properly generated pulse applied on
the DTR line 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:
1PPS Enable/Delay Setup:
1. The 1 PPS Enable/Delay parameter must be set to 0 in the Master.
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. Slaves are calibrated at the
factory.
Calibrating a Slave in 1PPS Enable/Delay mode
1. Trigger an oscilloscope on the 1 PPS pulse on the DTR line of the Master.
2. Monitor the CD line of the Slave.
3. 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 2mS 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)
SLAVE/REPEATER
The Slave/Repeater mode allows a transceiver in a MultiPoint network to switch between Slave and Repeater
functions. When in this mode, a transceiver will repeat any packets sent across the network as well as utilize
the RS232 port. Thus, where one Repeater and one Slave may be required in another vendor’s network,
FreeWave networks require only one transceiver. (This option is not available in Ethernet mode.)
Note: To operate a transceiver as a MultiPoint Slave/Repeater, the operation mode must be set to (7)
MultiPoint Repeater and Slave/Repeater set to 1 in the MultiPoint Parameters menu.
(B)
DIAGNOSTICS
This option provides diagnostics data to be viewed at the Master in parallel with application data. The
diagnostic program MUST be run from the Master transceiver. Diagnostics requires the following:
1. The Number Repeaters set to 1 and Diagnostics set to (1 to 128) in the Master.
2. A second computer or serial connection to run the diagnostics software.