Description
A Socket SendTo (Transmit Explicit Data) message causes the device to transmit data using an IPv6 address and port. For a non-zero frame ID, this will elicit a Transmit Status - 0x89 frame.
If this frame is used with a TCP or a connected UDP socket, the address and port fields are ignored.
You must perform a Socket Bind/Listen - 0x46 frame for a UDP connection before you attempt a SendTo in order to assign a source port.
Format
The following table provides the contents of the frame. For details on frame structure, see API Frames.
| Offset | Size | Frame Field | Description |
|---|---|---|---|
0 |
8-bit |
Start Delimiter |
Indicates the start of an API frame. |
1 |
16-bit |
Length |
Number of bytes between the length and checksum. |
3 |
8-bit |
Frame type |
0x45 |
4 |
8-bit |
Frame ID |
A reference identifier used to match status responses. If set to 0, the Transmit Status - 0x89 frame is disabled. |
5 |
8-bit |
Socket ID |
The socket ID to send on. |
6 |
128-bit |
Destination IPv6 Address |
The address to send to. |
22 |
16-bit |
Destination Port |
The port to send to. |
24 |
8-bit |
Transmit Options |
Reserved. |
25 |
variable |
Payload |
Data to be transferred to the destination. |
EOF |
8-bit |
Checksum |
0xFF minus the 8-bit sum of bytes from offset 3 to this byte (between length and checksum). |
