Extended Socket Frames; Examples - Digi XBee 3 Cellular LTE-M User Manual

Extended Socket frames

The XBee Cellular product line includes a set of Extended Socket frames. You can use these frames in
applications where the existing frames
(0xB0)) limit the possibilities for an application.
You can use Extended Socket frames to do the following:
Multiple simultaneous connections can be made to the same port on the same host. For
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example, you can overlap simultaneous HTTP requests.
Immediate unsolicited notification of changes in socket status. This allows an application to
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react to a server-side socket closure rather than relying on an implicit connection to be re-
established for continuing communication.
A generalized mechanism for per-socket option selection. Currently used for TLS profile
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selection. Previously this required a unique frame, as options are added, this allows
combinations of choices.
Allow DNS look up during the connection process rather than a separate step.
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In addition, for diagnostic purposes, you can use the
information regarding all open sockets currently active in the system. This can be queried during
development or used by an application to confirm or refresh information during execution.
Note Sockets opened with the Extended Socket frames cannot be used with the legacy frames
(Transmit Request
For a list of the socket frames, see

Examples

In the examples below the Frame IDs in all frames are set to 1 for simplicity. Socket IDs in all frames
after the Socket Create are hard-coded to 0 as well. If you wish to use the example repeatedly the
XBee should be rebooted between attempts.
We recommend the use of the XCTU frame generator for experimentation with frames during
development. Paste the provided frame content directly into the Add API frame to list window in
XCTU to follow along manually.
Extended Socket example: Single HTTP Connection
Extended Socket example: UDP
Extended Socket example: TCP Listener
Digi XBee® 3 Cellular LTE-M/NB-IoT Global Smart Modem User Guide
(Transmit Request
(0x20), TLS Transmit (0x23)
Available Extended Socket
(0x20), TLS Transmit (0x23)
Socket Info (SI) AT command to retrieve
and Receive (0xB0)), nor vice versa.
frames.
and Receive
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