Digi XBee Cellular LTE Cat 1, User Manual, Page: 76 / 91

Operate in API mode Frame descriptions
Digi XBee Cellular LTE Cat 1 Embedded Modem User Guide 76
Transmit (TX) Request: IPv4 - 0x20
Description
A TX Request message causes the device to transmit data in IPv4 format.
Format
The following table provides the contents of the frame. For details on frame structure, see API frame
specifications .
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 UDP or TCP port number.
To send a UDP packet, this must match the port number of
the listening port. To send a TCP packet on a new
connection, this must be
0 .
Protocol Byte 0 = UDP
1 = TCP
4 = SSL over TCP
Transmit options Byte
bitfield Bit 1: When set, close TCP socket immediately after transmit
success. All other bits are reserved and should be set to zero.
Payload Variable Data to be transferred to the destination, may be up to 1500
bytes.