47 lines
1.8 KiB
HTML
47 lines
1.8 KiB
HTML
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<!DOCTYPE html>
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<html>
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<head>
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<title>XSCHEM PRESENTATION</title>
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<link rel="stylesheet" type="text/css" href="xschem_man.css" />
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<style type="text/css">
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/* Local styling goes here */
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p{padding: 15px 30px 10px;}
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.content{ background-image:url('xschem_bg2.png');}
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</style>
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</head>
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<body>
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<!-- start of slide -->
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<div class="content">
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<!-- navigation buttons -->
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<a href="tutorial_xschem_slides05.html" class="prev">PREV</a>
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<a href="tutorial_xschem_slides01.html" class="home">UP</a>
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<a href="tutorial_xschem_slides061.html" class="next">NEXT</a>
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<!-- slide title -->
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<h1>HIERARCHY, SYMBOLS AND COMPONENT INSTANCES</h1>
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<h3 style="text-align:left; max-width: 55%;margin-left:0;">
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<ul style="margin-left:0;">
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<li>Describe complex circuits by using symbols.</li>
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<li>A component placed in a schematic is an instance of a
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<a href="http://repo.hu/projects/xschem/xschem_man/tutorial_create_symbol.html">symbol</a>.</li>
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<li>A symbol hides the underlying circuit, showing only the interface (pins) to the parent schematic.</li>
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<li>Repetitive blocks (registers, amplifiers, comparators, logic gates, ...) can be used multiple times in a design.</li>
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<li>When creating a netlist the circuit is traversed all the way from the top level down to the lowest level leaves.</li>
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<li>At the lowest level we have primitive symbols, these have attributes telling the netlister how to describe them.</li>
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<li>A symbol definition is stored in a .sym file (inv.sym), while the circuit implementation is in a .sch file (inv.sch).</li>
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</ul>
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</h3>
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<img src="tutorial_xschem_slides05.png" style="position:fixed; top:15%; right:2%;width:40%; max-width: 40%;">
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<!-- end of slide -->
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<div class="filler"></div>
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</div>
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<!-- frame footer -->
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<iframe seamless src="xschem_footer.html" class="footer_iframe" >
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</body>
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</html>
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