Transmit (TX) Request: IPv4 - 0x20
Description
A TX Request message causes the device to transmit data in IPv4 format. A TX request frame for a new destination creates a network socket. After the network socket is established, data from the network that is received on the socket is sent out the device's serial port in the form of a Receive (RX) Packet frame.
Format
The following table provides the contents of the frame. For details on frame structure, see API frame format.
| Field name | Field value | Data type | Description |
|---|---|---|---|
|
Frame type |
0x20 |
Byte |
|
|
Frame ID |
|
Byte |
Reference identifier used to match status responses. 0 disables the TX Status frame. |
|
Destination address |
|
32-bit big endian |
|
|
Destination port |
|
16-bit big endian |
|
| Source port |
16-bit big endian |
If the source port is 0, the device attempts to send the frame data using an existing open socket with a destination that matches the destination address and destination port fields of this frame. If there is no matching socket, then the device attempts to open a new socket. If the source port is non-zero, the device attempts to send the frame data using an existing open socket with a source and destination that matches the source port, destination address, and destination port fields of this frame. If there is no matching socket, it returns an error. |
|
|
Protocol |
|
Byte |
0 = UDP 1 = TCP 4 = SSL over TCP |
|
Transmit options |
|
Byte bitfield |
Bit fields are offset 0 Bit field 0 - 7. Bits 0, and 2-7 are reserved, bit 1 is not. BIT 1 = 1 - Terminate the TCP socket after transmission is complete 0 - Leave the socket open. Closed by timeout, see TM (IP Client Connection Timeout). Ignore this bit for UDP packets. All other bits are reserved and should be 0. |
|
Payload |
|
Variable |
Data to be transferred to the destination, may be up to 1500 bytes. |
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