Protocol Formatter (Async)

From GNU Radio
Jump to navigation Jump to search

Uses a header format object to append a header onto a PDU.

This block takes in PDUs and creates a header, generally for MAC-level processing. Each received PDU is assumed to be its own frame, so any fragmentation would be done upstream in or before the flowgraph.

The header that is created and transmitted out of the 'header' message port as a PDU. The header is based entirely on the object, which is an object derived from the header_format_base class. All of these packet header format objects operate the same: they take in the payload data as well as possible extra metadata info about the PDU; the format object then returns the output PDU as a PMT argument along with any changes to the metadata info PMT.

For different packet header formatting needs, we can define new classes that inherit from the header_format_base block and which overload the header_format_base::format function.


Parameters

Format Obj.
The format object to use when reading the header. This block uses a format object derived from a header_format_base class.

Example Flowgraph

This flowgraph can be found at [1]

Packet tx fg.png

Source Files

C++ files
[2]
Header files
[3]
Public header files
[4]
Block definition
[5]