Talk:Clock skew

Latest comment: 14 years ago by 129.132.28.20 in topic definition not correct

Include a simple definition

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This page doesn't give a high-level description of what clock skew is. In particular, it jumps immediately to circuit design. It would be much more useful to start by saying that clock skew is simply that two or more clocks are offset from each other by a constant.

Suggestion: If a clock has a positive drift compared to some reference clock, it simply means that it is ahead of the reference clock by some constant. Similarly, if a clock has a negative drift compared to some reference clock, it simply means that it is behind of the reference clock by some constant. If the drift is not constant, and changes over time, another phenomena is playing in, called clock skew (refer to the clock skew page). —Preceding unsigned comment added by 193.10.65.222 (talk) 10:14, 7 January 2009 (UTC)Reply

How about quoting from here?

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How to: Clock Skew Can Save Your Overclock And Memory

Dukeofgaming (talk) 17:16, 16 May 2009 (UTC)Reply

Jitter

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I think jitter should probably be included in the equations for beneficial clock skew. Fresheneesz 05:09, 18 May 2007 (UTC)Reply

Zero hold time is preferred?
Yes, I agree that jitter should be included. In addtion to it, why zero hold time is prefered for ICs should be included.
Should the word "cannot" be "can" in the statement?
Positive skew and negative skew cannot negatively impact setup and hold timing constraints respectively (see inequalities below).
Carl Horton 04:10, 18 November 2008

really two articles

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This is really two articles: one on circuits and one on networks. This should be split. Asmeurer (talkcontribs) 20:02, 7 December 2008 (UTC)Reply

error?

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In the "Beneficial skew" section H is the hold time of the destination register should not this be H is the hold time of the source! register, —Preceding unsigned comment added by 92.205.35.134 (talk) 01:34, 30 May 2009 (UTC)Reply

definition not correct

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The article says: "On a network such as the internet, clock skew describes the difference in time shown by the clocks at the different nodes on the network."

IMO this definition is not correct, see e.g. the definition in RFC 1305 where the difference in time is denoted as "offset" and the difference in frequency is denoted as "skew": "Unless indicated otherwise, the offset of two clocks is the time difference between them, while the skew is the frequency difference (first derivative of offset with time) between them. Real clocks exhibit some variation in skew (second derivative of offset with time), which is called drift; however, in this version of the specification the drift is assumed zero."

Gst (talk) 07:36, 11 August 2009 (UTC)Reply

I agree, for me the skew is also the first derivative. 129.132.28.20 (talk) 13:48, 23 November 2009 (UTC)Reply