Laird ConnexLink CL2510, User Manual

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Laird Technologies

CL2510

RF Transceiver

The CL2510 utilizes a Server-Client configuration to synchronize the frequency hopping of all devices in the 

network. The Server transmits a brief beacon immediately after hopping to a new frequency. This beacon  

contains information about the network and the hopping pattern. Client radios will synchronize to this beacon 

to ensure they are on the same frequency at the same time as the Server. The Client Link LED will light when 

the Client is synchronized to the Server.

Each network should consist of only one Server and there should never be two Servers on the same RF  
Channel and System ID in the same coverage area. Collocated Servers are permitted, provided the Servers  
are on different RF Channels. Additional Servers in the same coverage area will degrade the performance for  
all radios.  Interference will increase a maximum of 2.3% for each Server added when hopping over 43 hops 
and a maximum of 1.2% when hopping over 79 hops. Degradation may be transparent to the end user  
depending on the number of retries/attempts and the data rate.

mODES OF OPERATION

The CL2510 has two primary modes of operation:
Transparent Mode
Command Mode

Transmit mode is used to transmit serial data across the RF and Command Mode is used to reconfigure 

the CL2510.

TRANSmIT mODE

All packets sent over the RF are either Broadcast or Addressed (Unicast) packets.    

BROADCAST PACKETS

A Broadcast Packet is one that can be received by all eligible receivers on the network. To increase the  
reliability of the delivery of Broadcast packets, the transmitting radio will transmit the message the number  

of times specified by the Broadcast Attempts. Broadcast Attempts are necessary because Broadcast packets 

are not acknowledged by the receiving radio. Therefore, the transmitting radio has no method for guaranteeing 
receipt of the message. The default Broadcast Attempts is 3 and more or less may be necessary in different  
applications. Increasing Broadcast Attempts will increase the reliability of data at the cost of the overall 
throughput potential of the link. The receiving radio will not forward duplicate Broadcast packets on to the 
OEM host.

ADDRESSED PACKETS

An Addressed Packet is one that is only sent to a specific transceiver based upon the MAC address of the 

destination. Addressed packets are acknowledged by the receiving radio, so additional Transmit Retries will  
only be used if necessary. The transmitting radio will retry sending an Addressed Packet until all of the  
Transmit Retries have been used or until it receives a successful acknowledgement from the receiving radio.

COmmAND mODE

Command Mode is used to configure the transceiver. To enter Command Mode on the CL2510 the OEM host 
must send the AT Enter Command string “AT+++”. Once in Command Mode, all data received by the radio 

over the serial interface is interpreted as command data. Data received over the RF interface will be stored in 
the TX buffer until Command Mode is exited.

When using the Laird Technologies Configuration Utility, the OEM doesn’t need to worry about entering and 

exiting Command Mode, as the software will do that automatically. These details on Command Mode are pro-

vided for OEMs manually configuring the radio.

* Design Tip: Entering Command Mode.

A properly formed Enter AT Command string must be issued when the RX Serial buffer on the radio is empty.  
If data is either pre-pended or added to the AT string, the radio will not properly identify it as the AT Enter 
Command Mode command and will not enter Command Mode. It is suggested that the OEM host wait a  

sufficient period of time between the last data packet and the AT Enter Command Mode. This time varies 

depending on the amount of data being sent and the number of retries/attempts configured. Waiting at 

least 250ms should be sufficient for most applications.

THEORY OF  

OPERATION