       Welcome to the Allegro 5.0 Signoise On-line Tutorial

    This tutorial consists of a series of tutorial frames designed to
demonstrate Allegro's optional Signal Noise Analysis, SNA.  As designs 
become increasing fast and compact, layout requires consideration of noise
and timing constraints for 100% WORKING along with 100% routing.  SNA quickly 
finds signal voltage noise problems such as excessive layout crosstalk or
excessive delay from interconnects.  5.0 SNA even tracks down subtle,
layout related timing problems. This includes features to help 
identify  problems 
with distorted rise-or-fall times reaching receiver pins, 
or with excessive settling time, or with double
clocking due to reflections.
SNA is completely integrated into Allegro so you can 
interactively fix a problem in the layout and immediately verify the fix.

  *** Sequence and Content of Signoise Tutorial Frames ***

    Actions          Help filename     Content                     
    -------          -----------       -------                     
    introduction     sna-start         This intro page
    noise concepts   sna-concepts      Concepts of timing and noise
    signoise forms   sna-forms         Explains menus & forms
    signoise execute sna-sort          Finding marginal nets                  
    signoise execute sna-asttl         High speed technology problems  
    slide            sna-slide         Reducing crosstalk        
    change           sna-change        Controlling line impedance  
    delete           sna-delete        Terminators and waveforms       
    quit             sna-quit          Quit this tutorial

You may type "help filename" to view the instructions for some other
section. Type "help sna-start" to see this page again.  You may quit 
your allegro_editor or type "replay sna-quit" to end this tutorial.

 Subsequent help messages are to be viewed through a narrow window which
 you should scroll through by a left button click in this right border.->

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 Press keyboard <F1> to continue (with the cursor INSIDE this window)     
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  or   ...    Press keyboard <F3> to quit the tutorial at any time.

