Extended Socket example: UDP
UDP is connection-less, so this example demonstrates that a Socket Connect frame is not required to begin communication and that multiple peers can be used with a single socket.
Send a Socket Create frame
| Field | Value |
|---|---|
| Frame type |
0x40 (Socket Create) |
| Frame ID | 0x01 |
| Protocol | 0x00 (UDP) |
UDP Socket Create frame data:
7E 00 03 40 01 00 BE
Receive a Socket Create response
| Field | Value |
|---|---|
| Frame type | 0xC0 (Socket Create Response) |
| Frame ID | 0x01 |
| Socket ID | 0x00 |
| Status | 0x00 (Success) |
Socket Create Response received from XBee:
7E 00 04 C0 01 00 00 3E
Bind local source addres
The bind/listen operation is necessary prior to transmit in order to assign a known source address to all data sent from this socket.
| Field | Value |
|---|---|
| Frame type | 0x46 (Socket Bind/Listen) |
| Frame ID | 0x01 |
| Socket ID | 0x00 |
| Source Port | 0x12 0x34 |
Socket Bind/Listen frame data:
7E 00 05 46 01 00 12 34 72
Receive Bind/Listen Response
The XBee generates a response indicating the status of the request to bind the requested port.
| Field | Value |
|---|---|
| Frame type |
0xC6 (Socket Bind/Listen Response) |
| Frame ID | 0x01 |
| Socket ID | 0x00 |
| Status | 0x00 (Success) |
Socket Bind/Listen Response received from XBee:
7E 00 04 C6 01 00 00 38
Send to Digi echo server
Digi hosts a server at 52.43.121.77 port 10001 which echos all UDP traffic sent to it.
| Field | Value |
|---|---|
| Frame type |
0x45 (Socket SendTo) |
| Frame ID | 0x01 |
| Socket ID | 0x00 |
| Destination Address | 0x34 0x2B 0x79 0x4D (52.43.121.77) |
| Destination Port | 0x27 0x11 (decimal 10001) |
| Transmit Options | 0x00 |
| Payload | echo this |
Socket SendTo frame data:
7E 00 13 45 01 00 34 2B 79 4D 27 11 00 65 63 68 6F 20 74 68 69 73 E5
Receive TX Status
Extended sockets use the existing TX Status frame (0x89) to report acceptance of the data for transmit.
| Field | Value |
|---|---|
| Frame type |
0x89 (TX Status) |
| Frame ID | 0x01 |
| Status | 0x00 (Success) |
TX Status received from XBee:
7E 00 03 89 01 00 75
Receive echoed data
When the response from the server is sent back, the XBee provides it using a Socket Receive From frame.
| Field | Value |
|---|---|
| Frame type |
0xCE (Socket Receive From) |
| Frame ID | 0x00 |
| Socket ID | 0x00 |
| Source address | 0x34 0x2B 0x79 0x4D (52.43.121.77) |
| Source Port | 0x27 0x11 (decimal 10001) |
| Status | 0x00 (Success) |
| Payload | echo this |
Socket ReceiveFrom received from XBee, containing echoed data:
7E 00 13 CE 00 00 34 2B 79 4D 27 11 00 65 63 68 6F 20 74 68 69 73 5D
Send to Digi time server
Digi hosts a server at 54.43.121.77 port 10002 which will reply with the time when it receives a packet.
| Field | Value |
|---|---|
| Frame type |
0x45 (Socket SendTo) |
| Frame ID | 0x01 |
| Socket ID | 0x00 |
| Destination Address | 0x34 0x2B 0x79 0x4D (52.43.121.77) |
| Destination Port |
0x27 0x12 (decimal 10002) |
| Transmit Options | 0x00 |
| Payload | 0x20 (ASCII space, any value should do) |
Socket SendTo time server frame data:
7E 00 0B 45 01 00 34 2B 79 4D 27 12 00 20 3B
Receive TX Status
This is exactly the same as the previous transmission to the echo server on success.
Receive daytime value
When the response from the server is sent back, the XBee will provide it using a Socket Receive From frame.
| Field | Value |
|---|---|
| Frame type |
0xCE (Socket Receive From) |
| Frame ID | 0x00 |
| Socket ID | 0x00 |
| Source address | 0x34 0x2B 0x79 0x4D (52.43.121.77) |
| Source Port |
0x27 0x12 (decimal 10002) |
| Status | 0x00 (Success) |
| Payload | <current UTC time> |
Socket Receive From frame received from XBee containing time data:
7E 00 1E CE 00 00 34 2B 79 4D 27 12 00 32 30 31 39 2D 30 37 2D 31 38 20 31 38 3A 35 32 3A 34 33 0A 08
Close the socket
When the socket is no longer needed it should be closed to return resources to the system.
| Field | Value |
|---|---|
| Frame type |
0x43 (Socket Close) |
| Frame ID | 0x01 |
| Status | 0x00 |
Socket Close frame data:
7E 00 03 43 01 00 BB
Receive close response
Finally, the XBee indicates the socket has been closed with a Socket Close Response frame.
| Field | Value |
|---|---|
| Frame type |
0xC3 (Socket CloseResponse) |
| Frame ID | 0x01 |
| Socket ID | 0x00 |
| Status | 0x00 (Success) |
Socket Close Response received from XBee:
7E 00 04 C3 01 00 00 3B
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