RE: [sv-ec] What is meant by "simple edge"?

From: <jonathan.bromley_at_.....>
Date: Wed Aug 12 2009 - 15:00:38 PDT
Shalom,

> The clocking event may specify both edges, as in this example from the 
LRM:
> 
> clocking ck2 @(clk); // no edge specified!
>   default input #1step output negedge; // legal
>   input ... ;
>   output ... ;
> endclocking 

Hmmmm..... Can anyone shed any light on what that
could possibly mean?  Let's try to use it...

  @(negedge clk) #1;  // get to just after negedge
  @(ck2);  // get to rising edge
  ck2.some_output <= 1'b1;  // takes effect on next negedge
  @(ck2);  // get to negedge
  ck2.some_output <= 1'b0;  // now?  one whole cycle later?

Surely this is precisely the situation that the "simple edge"
wording was intended to avoid, and the example must be wrong?
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Jonathan Bromley
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Received on Wed Aug 12 15:01:26 2009

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