imported>Tuckertwo: Adding short description: "Line code"

2024-01-28T12:16:19Z

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{{Short description|Line code}}
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| [[image:Data_Strobe_Encoding.png]]
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|<small>''Data strobe encoding and recovered clock.''</small>
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'''Data strobe encoding''' (or '''D/S''' encoding) is an encoding scheme for transmitting data in [[digital circuit]]s.
It uses two signal lines (e.g. wires in a cable or traces on a [[printed circuit board]]), ''Data'' and ''Strobe''. These have the property that either Data or Strobe changes its [[Truth value|logical value]] in one [[clock cycle]], but never both. More precisely data is transmitted as-is and strobe changes its state if and only if data stays constant between two data bits.
This allows for easy [[clock recovery]] with a good [[jitter]] tolerance by [[XOR]]ing the two signal line values.<ref>{{cite book |last=Parkes |first=Steve |date=2012 |title=SpaceWire User's Guide |url=https://www.star-dundee.com/wp-content/star_uploads/2019/05/SpaceWire-Users-Guide.pdf |publisher=STAR-Dundee Limited |page=52 |isbn=978-0-9573408-0-0 }}</ref>

There is an equivalent way to specify the relationship between Data and Strobe.
For even-numbered Data bits, Strobe is the opposite of Data.
For odd-numbered Data bits, Strobe is the same as Data.
From this definition it is more obvious that the XOR of Data and Strobe will yield a clock signal. Also, it specifies the simplest means of generating the Strobe signal for a given Data stream.

Data strobe encoding originated in [[IEEE 1355]] Standard and is used on the signal lines in [[SpaceWire]] and the [[FireWire|IEEE 1394]] (also known as [[FireWire 400]]) system.

[[Gray code]] is another code that always changes one logical value, but never more than one.

==References==
{{Reflist}}

[[Category:Line codes]]

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Data strobe encoding - Revision history

imported>Tuckertwo: Adding short description: "Line code"