FreeWave Technologies Inc. AMI0032AT Manuale Utente

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 Spread Spectrum Wireless Data Transceiver User Manual 
Preliminary GXM Manual 
Version 0.2 
38 
PRELIMINARY 
(4)
 
DTR
 
C
ONNECT
 
With the setting of 0 in the Slave, the transceiver will transmit when RS232 data is received.  A setting of 
1 will form a Point-to-Point link with the Master when the DTR line is high.  With a setting of 2, the 
transceiver will transmit in bursts.  This mode is valuable when a network has many low data rate devices 
and it is desirable to increase overall network capacity.  
Note:
  If ‘DTRConnect’ is set to 1 and the ‘RTS to CTS’ function is enabled on the radio, then ‘RTS to 
CTS’ takes precedence over ‘DTRConnect’. 
 
Note:
  If ‘DTRConnect’ is set to ‘2’ and ‘RTS to CTS’ is enabled, then ‘RTS to CTS’ is ignored. The 
transceiver has two separate transmit and receive user data buffers.  For the FGR series radios, 
these buffers are 2 Kbytes each.  In case of a buffer overflow, the transceiver will output 
unpredictable data.  
(5)
 
R
EPEATER 
F
REQUENCY
 
Repeater Frequency must be set to a 1 in a Repeater when a FreqKey other than that of the Master is 
desired.  This condition occurs when parallel Repeaters in a network may have overlapping areas of 
responsibility.  The default setting of 0 causes the Repeater to use the FreqKey set in Menu 3.   
Note:
  When Repeater Frequency is set to 0 and Subnets are not configured, the FreqKey setting in 
each Slave must match the Master or Repeater acting as the Master for the transceiver.  
(6)
 
N
ETWORK 
ID 
NetWork ID allows MultiPoint networks to be established without using the Call Book.  The default setting 
of 255 enables the Call Book.  To enable NetWork ID the value must be set between 0 and 4095 
(excluding 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.  The Network ID function should be used in 
conjunction with the SubNet ID feature (If necessary). 
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)
 
M
ULTI
M
ASTER 
S
YNCH
 
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 
see application note #5412 “Synchronizing Collocated Masters” or contact FreeWave Technical support 
for more information.  
(9)
 
1
 
PPS
 
E
NABLE
/D
ELAY
 
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.