CL4790 User Guide
Version 2.0
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8
CONN-GUIDE_CL4790
When an addressed packet or a response to a broadcast packet is sent, the sending radio will listen for a
successful acknowledgement. If an acknowledgement is not sent, the radio will resend the packet until either
an acknowledgement is received or it has exhausted all available transmit retries. If two radios are on the last
hop of the current session and a retry is required, it is possible that once the current session has ended the
receiving radio could go into session with a different radio and miss the final packet of the previous session.
Adding the radios Transmit retries to its Current Session Count will ensure that the radio does not exit the
session when the remote radio is using a Transmit Retry.
Case 3
In this case a radio loads its Session Count with the remote radio's Session Count Refresh. This is suitable for
full duplex applications as the Session is extended as long as there is communication.
Note: This is the default case with which the radio ships and may not work well for all applications. Use
Case 4 when a large number of data packets are lost during operation.
Case 4
In this case, a radio loads its Session Count with the remote radio's current Session Count. This is suitable for
daisy chain applications and large networks in which radios cannot stay in session longer than needed. This
case guarantees that two radios will stay in session as long as they have data to communicate and will both
leave the session at the same time.
Command Mode
A radio enters Command mode when data is received over the serial interface from the OEM host and
contains the “AT+++” (Enter AT Command mode) command. Once in Command mode, all data received by
the radio is interpreted as command data. Command Data may exist as either EEPROM Configuration or On-
The-Fly commands. For more information on EEPROM Configuration and On-the-Fly commands, download
the
AC4790 Embedded Module User Manual
).
