CL4424 User’s Manual
6/21/2005
17
4.2.1 ConnexLink
Settings
Client/Server: Designates CL4424 type. In each network, there must be only one Server. All
other CL4424 units must be programmed as Clients. The number of Clients in the network is not
limited; however, if performance diminishes due to the number of CL4424s that need to access
the network, consider additional RF Networks.
Interface Baud Rate: This defines the baud rate used for communicating with the CL4424 over
the serial interface. The RF baud rate is fixed at 576kbps and is independent of the Interface
Baud Rate. The default baud rate setting is 115,200 bps unless the units have been pre-
configured by AeroComm. The Interface Baud Rate setting of the CL4424 must match the Baud
Rate setting of its host device.
Random Back Off: In an asynchronous network where any node can talk at any time, the
CL4424 can be programmed to use Random Back Off to mitigate the RF Link. If two nodes try to
send packets at the same time, the packets will collide over the RF and will not be received by
the destination node. If Random Back Off is enabled when this occurs, both radios will generate
a random amount of time (in 8ms increments) to wait before retrying.
Channel Number: The CL4424 is a frequency hopping transceiver. Each Channel Number
designates a unique hopping sequence and constitutes an independent network of CL4424
units. Up to 40 independent networks can be created (up to 20 in France). Multiple Servers
operating in the same coverage area must be programmed with different Channel Numbers to
prevent inoperability of the networks. The valid range of values for this field is 0 to 39.
Table 1 – US and International RF Channel Number Settings
Channel
Set
RF Channel Number
Range
Frequency Range
Countries
1
0 – 19
2406 – 2435MHz US,Canada, Europe, France
2
20 – 39
2444 – 2472MHz
US, Canada, Europe
Max Transmit Retries (For all Clients and for Servers in Point-to-Point networks): This value
represents the maximum number of times a particular data packet will be transmitted
unsuccessfully, or without an acknowledgement, before the CL4424 discards the packet. The
default value is 16 attempts. If communication is lost and the Client’s Link LED is on, try
increasing this value in small increments until communication is reestablished. The valid range
of values for this field is 0 to 255.
Broadcast Attempts (For Servers in Point-to-Multipoint networks): This value represents the
number of times a data packet will be transmitted by the Point-to-Multipoint Server. The default
value is 4 attempts. If communication is lost and the Clients’ Link LED is on, try increasing this
value in small increments until communication is reestablished. The valid range of values for this
field is 0 to 255.
System Identification:
A number from 0 to 256 that provides added security to each independent
network of CL4424 units. The System ID serves as an RF password to maintain secure transfers
of data. The System ID will not prevent inoperability that occurs from locating multiple Servers
with the same Channel Number in the same coverage area.
Important Note: Collocated CL4424 networks must operate on different Channel Numbers. All
units in a given CL4424 network must have identical Channel Numbers and System IDs.
