Difference between revisions of "Protocol Parser"

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(Created page with "Category:Block Docs Category:Stub Docs This is the template for the "Page-per-block Docs". This first section should describe what the block...")
 
(add example flowgraph)
 
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[[Category:Block Docs]]
 
[[Category:Block Docs]]
[[Category:Stub Docs]]
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Block that synchronizes to a header based on a header format object class. Designed to accept hard bits and produce PDUs with packed bytes (pmt::u8vector).
This is the template for the [[:Category:Block_Docs|"Page-per-block Docs"]].  This first section should describe what the block does and how to use it, using however many paragraphs necessary.  Note that the title of the wiki page should match the block's name in GRC, i.e. the one defined in the block's .grc file.  Look at the [[FFT]] Block for a good example.
 
  
As this is a basic template, it's also in the [[:Category:Stub_Docs|"Stub Docs category"]]. Please improve it.
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This block takes in hard bits (unpacked bytes; 1's and 0's as the LSB) and finds the access code as a sync word to find the start of a frame.
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Once the frame is detected (usually through the use of an access code), the block uses the format object's parser function to decode the remaining header. Generally, as in the default header case, the header will contain the length of the frame's payload. That and anything else in the header will generally go into the PDU's meta-data dictionary.
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The block will output a PDU that contains frame's header info in the meta-data portion of the PDU and the payload itself. The payload is packed hard bits as taken from the input stream.
  
 
== Parameters ==
 
== Parameters ==
(''R''): <span class="plainlinks">[https://wiki.gnuradio.org/index.php/GNURadioCompanion#Variable_Controls ''Run-time adjustable'']</span>
 
  
; Param 1 (''R'')
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; Format Obj.
: Description of parameter, provide any tips or recommended values.  Note that the name of the parameter above should match the param's label that shows up in grc (e.g. Sample Rate).
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: The format object to use when reading the header. This block uses a format object derived from a header_format_base class.
  
; Param 2
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== Example Flowgraph ==
: blah blah blah
 
  
== Example Flowgraph ==
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This flowgraph can be found at [https://github.com/gnuradio/gnuradio/blob/master/gr-digital/examples/packet/packet_rx.grc]
  
Insert description of flowgraph here, then show a screenshot of the flowgraph and the output if there is an interesting GUI.  Currently we have no standard method of uploading the actual flowgraph to the wiki or git repo, unfortunately.  The plan is to have an example flowgraph showing how the block might be used, for every block, and the flowgraphs will live in the git repo.
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[[File:Packet_rx_fg.png|800px]]
  
 
== Source Files ==
 
== Source Files ==
  
 
; C++ files
 
; C++ files
: [https://github.com/gnuradio/gnuradio TODO]
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: [https://github.com/gnuradio/gnuradio/blob/master/gr-digital/lib/protocol_parser_b_impl.cc]
  
 
; Header files
 
; Header files
: [https://github.com/gnuradio/gnuradio TODO]
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: [https://github.com/gnuradio/gnuradio/blob/master/gr-digital/lib/protocol_parser_b_impl.h]
  
 
; Public header files
 
; Public header files
: [https://github.com/gnuradio/gnuradio TODO]
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: [https://github.com/gnuradio/gnuradio/blob/master/gr-digital/include/gnuradio/digital/protocol_parser_b.h]
  
 
; Block definition
 
; Block definition
: [https://github.com/gnuradio/gnuradio TODO]
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: [https://github.com/gnuradio/gnuradio/blob/master/gr-digital/grc/digital_protocol_parser_b.block.yml]

Latest revision as of 01:07, 7 April 2021

Block that synchronizes to a header based on a header format object class. Designed to accept hard bits and produce PDUs with packed bytes (pmt::u8vector).

This block takes in hard bits (unpacked bytes; 1's and 0's as the LSB) and finds the access code as a sync word to find the start of a frame.

Once the frame is detected (usually through the use of an access code), the block uses the format object's parser function to decode the remaining header. Generally, as in the default header case, the header will contain the length of the frame's payload. That and anything else in the header will generally go into the PDU's meta-data dictionary.

The block will output a PDU that contains frame's header info in the meta-data portion of the PDU and the payload itself. The payload is packed hard bits as taken from the input stream.

Parameters[edit]

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[edit]

This flowgraph can be found at [1]

Packet rx fg.png

Source Files[edit]

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