Difference between revisions of "Delay"

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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...")
 
 
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[[Category:Block Docs]]
[[Category:Block Docs]]
[[Category:Stub Docs]]
Delay the input by a certain number of samplesPositive delays insert zero items at the beginning of the stream. Negative delays discard items from the stream.  You cannot initialize this block with a negative delay, however. That leads to a causality issue with the buffers when they are initialized. If you need to negatively delay one path, then put the positive delay on the other path instead.
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.
Note that users have had issues when delaying by very large numbers.  


== Parameters ==
== Parameters ==
(''R''): <span class="plainlinks">[https://wiki.gnuradio.org/index.php/GNURadioCompanion#Variable_Controls ''Run-time adjustable'']</span>
(''R''): <span class="plainlinks">[https://wiki.gnuradio.org/index.php/GNURadioCompanion#Variable_Controls ''Run-time adjustable'']</span>


; Param 1 (''R'')
; Delay (''R'')
: 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).
: Number of samples/items to delay by


; Param 2
== Example Flowgraph ==
: blah blah blah


== Example Flowgraph ==
This flowgraph is taken from the [[Guided_Tutorial_PSK_Demodulation|QPSK Modulation / Demodulation]] tutorial. The Delay is used to match the transmit data to the receive data.


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.
[[File:Stage6_grc.png|800px]]


== Source Files ==
== Source Files ==


; C++ files
; C++ files
: [https://github.com/gnuradio/gnuradio TODO]
: [https://github.com/gnuradio/gnuradio/blob/main/gr-blocks/lib/delay_impl.cc delay_impl.cc]


; Header files
; Header files
: [https://github.com/gnuradio/gnuradio TODO]
: [https://github.com/gnuradio/gnuradio/blob/main/gr-blocks/lib/delay_impl.h delay_impl.h]


; Public header files
; Public header files
: [https://github.com/gnuradio/gnuradio TODO]
: [https://github.com/gnuradio/gnuradio/blob/main/gr-blocks/include/gnuradio/blocks/delay.h delay.h]


; Block definition
; Block definition
: [https://github.com/gnuradio/gnuradio TODO]
: [https://github.com/gnuradio/gnuradio/blob/main/gr-blocks/grc/blocks_delay.block.yml blocks_delay.block.yml]

Latest revision as of 13:28, 26 January 2022

Delay the input by a certain number of samples. Positive delays insert zero items at the beginning of the stream. Negative delays discard items from the stream. You cannot initialize this block with a negative delay, however. That leads to a causality issue with the buffers when they are initialized. If you need to negatively delay one path, then put the positive delay on the other path instead.

Note that users have had issues when delaying by very large numbers.

Parameters[edit]

(R): Run-time adjustable

Delay (R)
Number of samples/items to delay by

Example Flowgraph[edit]

This flowgraph is taken from the QPSK Modulation / Demodulation tutorial. The Delay is used to match the transmit data to the receive data.

Stage6 grc.png

Source Files[edit]

C++ files
delay_impl.cc
Header files
delay_impl.h
Public header files
delay.h
Block definition
blocks_delay.block.yml