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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<head>
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<meta http-equiv="CONTENT-TYPE" content="text/html; charset=utf-8">
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<title>signal,port and pad naming guidelines</title>
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<meta name="KEYWORDS" content="start">
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<meta name="Info 3" content="">
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<meta name="Info 4" content="">
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<meta name="date" content="2008-01-08T12:01:41-0500">
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</head>
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<body dir="ltr" lang="en-US">
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<div id="toc__header" dir="ltr">
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<p><br>
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<br>
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</p>
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</div>
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<h1><a name="socgen_project"></a>SOCGEN Project</h1>
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<h2>Signal,Port and Pad Naming Guidelines</h2>
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<p><br>
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<br>
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</p>
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<p>As designs and design teams continue to grow in size it is mandatory
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that all rtl code must follow established name space guidelines. The
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days when designers could simply pull names out of thin air are faster
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disappearing. Naming guidelines have three functions. First they
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ensure that no two designers select the same name for different objects
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and have a name collision. The second function is to ensure that the
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chosen names are meaningful to all of the design team. It is quite
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common for designers to select names
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that only make sense to themselves and no one else on the team. The
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third function
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is to ensure that all rtl code follows a consistent format so that it
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may be parsed
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by various eda tools.
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</p>
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<h3 class="western"><br>
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</h3>
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<h3 class="western"><br>
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</h3>
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<h3 class="western"><br>
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</h3>
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<h3 class="western">Signal ,Port and Pad Names<br>
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</h3>
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<p>Signals define the nodes inside of a component and each node
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must have a unique name. That signal name becomes the port name when a
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node is ported up the hierarchy. The port names become the pad names at
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the top level. All of these exist in the same name space along
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with other items such as instance names. Managing this name space is
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crucial.<br>
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</p>
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<p><br>
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There are two distinct groups that use these names. The IC design team
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is one group and it will use all three. The other group consists
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of System designers,PCB designers, Board Test engineers etc.<br>
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They only access the chip via the pad names and never see the internal
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ones. These two groups have incompatible objectives. The IC
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design team is dealing with millions of names and needs a naming scheme
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that produces long descriptive names that won't collide and conveys
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information about the signals function. <br>
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</p>
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<p>The rest of the world is only dealing with a few hundred or thousand
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names. They also have their own naming requirements. These typically
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are:<br>
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</p>
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<p><br>
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</p>
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<ul>
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<li>Short Names that fit on a schematic graphic symbol. If you
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have 99 short names and 1 long one then you have a long column and
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wasted white space on your schematic.</li>
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</ul>
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<br>
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<ul>
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<li>Capital Letters. They make a packed schematic
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readable. You don't want your board designers trying to guess if it's a
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1 or a l.</li>
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</ul>
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<br>
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<ul>
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<li>ATE naming requirements. Do you know what the IEEE 1149.1
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pad naming rules are? If not then you shouldn't be selecting pad names.</li>
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</ul>
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<br>
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<br>
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The guideline for selecting pad names is that the IC design team should
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not attempt to pick pad names based on the internal signal names.
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They should first meet all of the PCA customers requirements without
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regard to what names are chosen for the internal signals. Name
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collisions are avoided by ensuring that ALL pad names start with a
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capital letter and that all internal names start with a small
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one. <br>
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<br>
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<br>
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For internal signal and port names you must first find the four pieces
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of information that will uniquely identify every signal in the design.
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These are:<br>
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<br>
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<br>
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<ul>
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<li>Interface Name You don't want 5 different ways
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to spell clock in a design. Each team must agree
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on common signal names and everyone must follow the rules. These
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are called standard interfaces. The team must create a document that
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lists all the standard interfaces and their names. It is
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ESSENTIAL that once a standard is chosen then all signals covered by
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that standards MUST follow the naming rules and the no signals that are
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not covered by the standard are allowed to use its name.<br>
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</li>
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</ul>
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<br>
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<ul>
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<li>Sub_member If the standard
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interface has more than one signal then you must also define the
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names for each sub_member as part of the standard <br>
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</li>
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</ul>
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<br>
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<br>
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<ul>
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<li>ad
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hoc
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If a signal is not defined by a standard interface then an ad hoc
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signal can be created based on the designers insight. If a module has 2
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or more signals with the same standard interface then a ad hoc field is
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needed to distinguish between them.</li>
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</ul>
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<br>
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<ul>
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<li>Driving Instance This is the instance name that
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is driving the signal. Wired or tristate logic is not allowed. There
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will be one and only one driver per node.</li>
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</ul>
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<br>
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<br>
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<br>
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You can create signal names by simply gathering this information and
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concatenating it into a name but it is perfectly acceptable to
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drop any field(s) if they are not needed to uniquely identify a node.<br>
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For example a IC design may have a signal named "clk". Clk is the
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standard interface name for a clock signal so we know that it is a
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clock. The clock interface has two sub_members - rising edge and
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falling edge. If you have N sub_members then you only have to
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identify N-1 of them. In this case the standard chooses _n for falling
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edge clocks and nothing for rising edge. clk is a rising edge clock. An
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ad hoc field is needed if the design has more than one clock and we
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have several - 2x, 4x 1.5 x etc. But again we only have to add this to
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all but one of the clocks. clk is a 1x clock. This design only has one
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clock generator so we don't need to add the driving instance. If
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a second clock generator is added then all of those clocks must include
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the driving instance in their name.<br>
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<br>
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<br>
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Besides defining all of the standard interfaces the design team must
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also define a field separator such as _ (underscore) as the way to
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separate the different fields that are combined to make a signal or
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port name. But the most important decision of all is the order
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that the fields are assembled to make up a name. This is like the Big
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Endian/Little Endian issue. They both have their strengths and
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weaknesses and it really doesn't matter which one you pick. BUT it is
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essential that the design team picks one and everybody does it that
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way. <br>
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<br>
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Signal and port names are even worse because with four fields you can
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have 24 possible signal names for each node. Unless everyone on
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the design team adheres to one order then it will be chaos when you try
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to architect and synthesize a design.<br>
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<br>
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<br>
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<br>
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<br>
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The recommended order for fields in a signal/port name is<br>
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<br>
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<br>
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<br>
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Driving_instance_(sep)_Ad
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hoc_(sep)_Interface_(sep)_Sub_member<br>
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<br>
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<br>
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<br>
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This ordering gives us the ability to have our signal names follow
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their function as the signals pass up and down the hierarchy. It also
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gives us an easy rule to follow when we need to pick a signal name. All
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that you need to do is find the instance name of the module that is
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driving that signal and combine it with the port name from that
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module. Since instance names are unique inside a design and port
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names are unique inside of a module then this rule guarantees that no
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other signal will use that name.<br>
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<br>
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By following this rule a signal name will grow as it progresses up the
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hierarchy. At each new level a new instance name is
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stuck on the front end and the instance name
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from the lower level becomes part of the ad hoc field. Each
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name contains a history of how it was created and what it does.<br>
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<br>
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<br>
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There are some special cases that can occur and these rules should be
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followed:<br>
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<br>
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<br>
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<ul>
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<li>There is one sub_member that can be used on a ad hoc signal
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that is not defined as a standard interface. That sub_member is active
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low (_n).</li>
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</ul>
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<br>
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<ul>
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<li>If a standard interface includes a signal that is itself defined
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as another standard interface then the interface name of the
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child becomes the sub member name for the parent. This usually occurs
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when a clock or reset is included in a bus interface. This ensures that
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when parsing the signal name it will match on both interfaces. If there
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are multiples of this interface then a ad hoc field must be perpended
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to the sub_member interface.</li>
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</ul>
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<br>
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<ul>
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<li>If the driving instance is not known such as a module where the
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signal is an input port then the instance and port of a receiving
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instance may be used instead.</li>
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</ul>
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<br>
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<br>
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<br>
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Again remember that any field may be dropped if it is not needed to
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uniquely identify the node<br>
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<br>
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<br>
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<br>
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<img style="width: 800px; height: 600px;" alt=""
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jt_eaton |
src="../png/naming_guide_1.png"><br>
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<p><br>
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<br>
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<br>
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Here is an example of how this works in a real design. A router IC has
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24 instances of a ethernet interface. Each instance controls a transmit
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sram buffer and a receive sram buffer. There are four instances in a
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bank and the bank is instantiated six times. The receive write
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data for the third interface in the second bank
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originates in a register bank deep inside a submodule. The name
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of this register is sram_wdata and that was chosen because the sram bus
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is a standard interface and wdata is the sub_member for the wdata. As
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it passes through the hierarchy the driving instance name is prepended
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on the front. It always parses as a sram wdata signal but the ad hoc
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field keeps growing.</p>
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<p><br>
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If the clock signal is also included in the sram interface then it's
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name would be:</p>
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<p> <br>
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</p>
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<p>
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bank_2_eth_3_sram_clk<br>
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<br>
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</p>
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<p>It would parse as both a clock signal and a sram signal. If this
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were a dual port sram then the signal would be:</p>
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<p><br>
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</p>
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<p>
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bank_2_eth_3_sram_a_clk <br>
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</p>
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<p><br>
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</p>
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<p>Notice that there is an ad hoc field both before and after the sram
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interface name and it still parses as both a clock and a sram signal.<br>
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</p>
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<p><br>
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</p>
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<p>If you want to synthesize the bank of 4 controllers then you will
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need to set an output delay on the sram outputs as a placeholder for
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the setup and routing delays in the full chip. To do this you need the
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full instance name of the source registers as seen from the top level.
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Assuming you use the standard _reg convention it would be:<br>
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</p>
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<p><br>
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eth_3/rx/sram_wdata_reg<br>
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</p>
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<p><br>
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</p>
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<p><br>
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</p>
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<p><br>
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</p>
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</p>
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<br>
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<p><br>
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</p>
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<h2>Standard Interfaces<br>
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</h2>
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<p></p>
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<p><br>
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</p>
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|
|
<p><br>
|
350 |
|
|
</p>
|
351 |
|
|
|
352 |
|
|
|
353 |
|
|
<h3 class="western">Clock <br></h3>
|
354 |
|
|
<p><br>
|
355 |
|
|
A clock is a signal that drives the clock port of a flipflop.<br>
|
356 |
|
|
</p>
|
357 |
|
|
<br>
|
358 |
|
|
<table style="text-align: left; width: 500px; height: 120px;" border="8" cellpadding="4" cellspacing="4">
|
359 |
|
|
<tbody>
|
360 |
|
|
<tr>
|
361 |
|
|
<td style="vertical-align: top;">Interface<br> </td>
|
362 |
|
|
<td style="vertical-align: top;">Clock<br> </td>
|
363 |
|
|
<td style="vertical-align: top;">Name<br> </td>
|
364 |
|
|
<td style="vertical-align: top;">Sub <br> </td>
|
365 |
|
|
</tr>
|
366 |
|
|
<tr>
|
367 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
368 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
369 |
|
|
<td style="vertical-align: top;">CLK<br> </td>
|
370 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
371 |
|
|
</tr>
|
372 |
|
|
<tr>
|
373 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
374 |
|
|
<td style="vertical-align: top;">Rising Edge<br> </td>
|
375 |
|
|
<td style="vertical-align: top;">CLK<br> </td>
|
376 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
377 |
|
|
</tr>
|
378 |
|
|
<tr>
|
379 |
|
|
<td style="vertical-align: top;"><br> </td>
|
380 |
|
|
<td style="vertical-align: top;">Falling Edge<br> </td>
|
381 |
|
|
<td style="vertical-align: top;">CLK<br> </td>
|
382 |
|
|
<td style="vertical-align: top;">_N<br> </td>
|
383 |
|
|
</tr>
|
384 |
|
|
</tbody>
|
385 |
|
|
</table>
|
386 |
|
|
<br>
|
387 |
|
|
<br>
|
388 |
|
|
<br>
|
389 |
|
|
|
390 |
|
|
|
391 |
|
|
|
392 |
|
|
<h3 class="western">Reset <br></h3>
|
393 |
|
|
<p><br>
|
394 |
|
|
A reset is a signal forces nodes into a known safe state<br>
|
395 |
|
|
</p>
|
396 |
|
|
<br>
|
397 |
|
|
<table style="text-align: left; width: 500px; height: 120px;" border="8" cellpadding="4" cellspacing="4">
|
398 |
|
|
<tbody>
|
399 |
|
|
<tr>
|
400 |
|
|
<td style="vertical-align: top;">Interface<br> </td>
|
401 |
|
|
<td style="vertical-align: top;">Reset<br> </td>
|
402 |
|
|
<td style="vertical-align: top;">Name<br> </td>
|
403 |
|
|
<td style="vertical-align: top;">Sub <br> </td>
|
404 |
|
|
</tr>
|
405 |
|
|
<tr>
|
406 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
407 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
408 |
|
|
<td style="vertical-align: top;">RESET<br> </td>
|
409 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
410 |
|
|
</tr>
|
411 |
|
|
<tr>
|
412 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
413 |
|
|
<td style="vertical-align: top;">Active high sync<br> </td>
|
414 |
|
|
<td style="vertical-align: top;">RESET<br> </td>
|
415 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
416 |
|
|
</tr>
|
417 |
|
|
<tr>
|
418 |
|
|
<td style="vertical-align: top;"><br> </td>
|
419 |
|
|
<td style="vertical-align: top;">Active Low async<br> </td>
|
420 |
|
|
<td style="vertical-align: top;">RESET<br> </td>
|
421 |
|
|
<td style="vertical-align: top;">_N<br> </td>
|
422 |
|
|
</tr>
|
423 |
|
|
</tbody>
|
424 |
|
|
</table>
|
425 |
|
|
<br>
|
426 |
|
|
<br>
|
427 |
|
|
<br>
|
428 |
|
|
|
429 |
|
|
|
430 |
|
|
|
431 |
|
|
|
432 |
|
|
|
433 |
|
|
<h3 class="western">Pads <br></h3>
|
434 |
|
|
<p><br>
|
435 |
|
|
Pads are the connections made between the pad_ring and the core.<br>
|
436 |
|
|
</p>
|
437 |
|
|
<br>
|
438 |
|
|
<table style="text-align: left; width: 500px; height: 120px;" border="8" cellpadding="4" cellspacing="4">
|
439 |
|
|
<tbody>
|
440 |
|
|
<tr>
|
441 |
|
|
<td style="vertical-align: top;">Interface<br> </td>
|
442 |
|
|
<td style="vertical-align: top;">Pads<br> </td>
|
443 |
|
|
<td style="vertical-align: top;">Name<br> </td>
|
444 |
|
|
<td style="vertical-align: top;">Sub <br> </td>
|
445 |
|
|
</tr>
|
446 |
|
|
<tr>
|
447 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
448 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
449 |
|
|
<td style="vertical-align: top;">PAD<br> </td>
|
450 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
451 |
|
|
</tr>
|
452 |
|
|
<tr>
|
453 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
454 |
|
|
<td style="vertical-align: top;">output<br> </td>
|
455 |
|
|
<td style="vertical-align: top;">PAD<br> </td>
|
456 |
|
|
<td style="vertical-align: top;">_OUT <br> </td>
|
457 |
|
|
</tr>
|
458 |
|
|
<tr>
|
459 |
|
|
<td style="vertical-align: top;"><br> </td>
|
460 |
|
|
<td style="vertical-align: top;">Input<br> </td>
|
461 |
|
|
<td style="vertical-align: top;">PAD<br> </td>
|
462 |
|
|
<td style="vertical-align: top;">_IN<br> </td>
|
463 |
|
|
</tr>
|
464 |
|
|
<tr>
|
465 |
|
|
<td style="vertical-align: top;"><br> </td>
|
466 |
|
|
<td style="vertical-align: top;">Enable<br> </td>
|
467 |
|
|
<td style="vertical-align: top;">PAD<br> </td>
|
468 |
|
|
<td style="vertical-align: top;">_OE<br> </td>
|
469 |
|
|
</tr>
|
470 |
|
|
</tbody>
|
471 |
|
|
</table>
|
472 |
|
|
<br>
|
473 |
|
|
<br>
|
474 |
|
|
<br>
|
475 |
|
|
|
476 |
|
|
|
477 |
|
|
|
478 |
|
|
<h3 class="western">Sram <br></h3>
|
479 |
|
|
<p><br>
|
480 |
|
|
Sram signals connect between the core and an instantiated memory cell.<br>
|
481 |
|
|
</p>
|
482 |
|
|
<br>
|
483 |
|
|
<table style="text-align: left; width: 500px; height: 120px;" border="8" cellpadding="4" cellspacing="4">
|
484 |
|
|
<tbody>
|
485 |
|
|
<tr>
|
486 |
|
|
<td style="vertical-align: top;">Interface<br> </td>
|
487 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
488 |
|
|
<td style="vertical-align: top;">Name<br> </td>
|
489 |
|
|
<td style="vertical-align: top;">Sub <br> </td>
|
490 |
|
|
</tr>
|
491 |
|
|
<tr>
|
492 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
493 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
494 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
495 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
496 |
|
|
</tr>
|
497 |
|
|
<tr>
|
498 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
499 |
|
|
<td style="vertical-align: top;">RW Address<br> </td>
|
500 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
501 |
|
|
<td style="vertical-align: top;">_ADDR <br> </td>
|
502 |
|
|
</tr>
|
503 |
|
|
<tr>
|
504 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
505 |
|
|
<td style="vertical-align: top;">Read Address<br> </td>
|
506 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
507 |
|
|
<td style="vertical-align: top;">_RADDR <br> </td>
|
508 |
|
|
</tr>
|
509 |
|
|
<tr>
|
510 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
511 |
|
|
<td style="vertical-align: top;">Write Address<br> </td>
|
512 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
513 |
|
|
<td style="vertical-align: top;">_WADDR <br> </td>
|
514 |
|
|
</tr>
|
515 |
|
|
<tr>
|
516 |
|
|
<td style="vertical-align: top;"><br> </td>
|
517 |
|
|
<td style="vertical-align: top;">Write Data<br> </td>
|
518 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
519 |
|
|
<td style="vertical-align: top;">_WDATA<br> </td>
|
520 |
|
|
</tr>
|
521 |
|
|
<tr>
|
522 |
|
|
<td style="vertical-align: top;"><br> </td>
|
523 |
|
|
<td style="vertical-align: top;">Read Data<br> </td>
|
524 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
525 |
|
|
<td style="vertical-align: top;">_RDATA<br> </td>
|
526 |
|
|
</tr>
|
527 |
|
|
|
528 |
|
|
|
529 |
|
|
|
530 |
|
|
<tr>
|
531 |
|
|
<td style="vertical-align: top;"><br> </td>
|
532 |
|
|
<td style="vertical-align: top;">Ram Select<br> </td>
|
533 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
534 |
|
|
<td style="vertical-align: top;">_CS<br> </td>
|
535 |
|
|
</tr>
|
536 |
|
|
|
537 |
|
|
|
538 |
|
|
<tr>
|
539 |
|
|
<td style="vertical-align: top;"><br> </td>
|
540 |
|
|
<td style="vertical-align: top;">Write Enable<br> </td>
|
541 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
542 |
|
|
<td style="vertical-align: top;">_WR<br> </td>
|
543 |
|
|
</tr>
|
544 |
|
|
|
545 |
|
|
|
546 |
|
|
<tr>
|
547 |
|
|
<td style="vertical-align: top;"><br> </td>
|
548 |
|
|
<td style="vertical-align: top;">Read Enable<br> </td>
|
549 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
550 |
|
|
<td style="vertical-align: top;">_RD<br> </td>
|
551 |
|
|
</tr>
|
552 |
|
|
|
553 |
|
|
<tr>
|
554 |
|
|
<td style="vertical-align: top;"><br> </td>
|
555 |
|
|
<td style="vertical-align: top;">Bit Write Enable<br> </td>
|
556 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
557 |
|
|
<td style="vertical-align: top;">_BE<br> </td>
|
558 |
|
|
</tr>
|
559 |
|
|
|
560 |
|
|
<tr>
|
561 |
|
|
<td style="vertical-align: top;"><br> </td>
|
562 |
|
|
<td style="vertical-align: top;">Clock<br> </td>
|
563 |
|
|
<td style="vertical-align: top;">SRAM<br> </td>
|
564 |
|
|
<td style="vertical-align: top;">_CLK<br> </td>
|
565 |
|
|
</tr>
|
566 |
|
|
|
567 |
|
|
|
568 |
|
|
|
569 |
|
|
</tbody>
|
570 |
|
|
</table>
|
571 |
|
|
<br>
|
572 |
|
|
<br>
|
573 |
|
|
<br>
|
574 |
|
|
|
575 |
|
|
<h3 class="western">Wishbone Bus <br></h3>
|
576 |
|
|
<p><br>
|
577 |
|
|
The wishbone bus provides microprocessor interconnection .<br>
|
578 |
|
|
</p>
|
579 |
|
|
<br>
|
580 |
|
|
<table style="text-align: left; width: 500px; height: 120px;" border="8" cellpadding="4" cellspacing="4">
|
581 |
|
|
<tbody>
|
582 |
|
|
<tr>
|
583 |
|
|
<td style="vertical-align: top;">Interface<br> </td>
|
584 |
|
|
<td style="vertical-align: top;">Wishbone<br> </td>
|
585 |
|
|
<td style="vertical-align: top;">Name<br> </td>
|
586 |
|
|
<td style="vertical-align: top;">Sub <br> </td>
|
587 |
|
|
</tr>
|
588 |
|
|
<tr>
|
589 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
590 |
|
|
<td style="vertical-align: top;">Address<br> </td>
|
591 |
|
|
<td style="vertical-align: top;">WB<br> </td>
|
592 |
|
|
<td style="vertical-align: top;">_ADR<br> </td>
|
593 |
|
|
</tr>
|
594 |
|
|
<tr>
|
595 |
|
|
<td style="vertical-align: top;"> <br> </td>
|
596 |
|
|
<td style="vertical-align: top;">Write Data<br> </td>
|
597 |
|
|
<td style="vertical-align: top;">WB<br> </td>
|
598 |
|
|
<td style="vertical-align: top;"> _WDAT<br> </td>
|
599 |
|
|
</tr>
|
600 |
|
|
<tr>
|
601 |
|
|
<td style="vertical-align: top;"><br> </td>
|
602 |
|
|
<td style="vertical-align: top;">Read Data<br> </td>
|
603 |
|
|
<td style="vertical-align: top;">WB<br> </td>
|
604 |
|
|
<td style="vertical-align: top;">_RDAT<br> </td>
|
605 |
|
|
</tr>
|
606 |
|
|
<tr>
|
607 |
|
|
<td style="vertical-align: top;"><br> </td>
|
608 |
|
|
<td style="vertical-align: top;">Write Enable<br> </td>
|
609 |
|
|
<td style="vertical-align: top;">WB<br> </td>
|
610 |
|
|
<td style="vertical-align: top;">_WE<br> </td>
|
611 |
|
|
</tr>
|
612 |
|
|
<tr>
|
613 |
|
|
<td style="vertical-align: top;"><br> </td>
|
614 |
|
|
<td style="vertical-align: top;">Byte Select<br> </td>
|
615 |
|
|
<td style="vertical-align: top;">WB<br> </td>
|
616 |
|
|
<td style="vertical-align: top;">_SEL<br> </td>
|
617 |
|
|
</tr>
|
618 |
|
|
<tr>
|
619 |
|
|
<td style="vertical-align: top;"><br> </td>
|
620 |
|
|
<td style="vertical-align: top;">Cycle<br> </td>
|
621 |
|
|
<td style="vertical-align: top;">WB<br> </td>
|
622 |
|
|
<td style="vertical-align: top;">_CYC<br> </td>
|
623 |
|
|
</tr>
|
624 |
|
|
<tr>
|
625 |
|
|
<td style="vertical-align: top;"><br> </td>
|
626 |
|
|
<td style="vertical-align: top;">Data Strobe<br> </td>
|
627 |
|
|
<td style="vertical-align: top;">WB<br> </td>
|
628 |
|
|
<td style="vertical-align: top;">_STB<br> </td>
|
629 |
|
|
</tr>
|
630 |
|
|
<tr>
|
631 |
|
|
<td style="vertical-align: top;"><br> </td>
|
632 |
|
|
<td style="vertical-align: top;">Acknowledge<br> </td>
|
633 |
|
|
<td style="vertical-align: top;">WB<br> </td>
|
634 |
|
|
<td style="vertical-align: top;">_ACK<br> </td>
|
635 |
|
|
</tr>
|
636 |
|
|
<tr>
|
637 |
|
|
<td style="vertical-align: top;"><br> </td>
|
638 |
|
|
<td style="vertical-align: top;">CTI<br> </td>
|
639 |
|
|
<td style="vertical-align: top;">WB<br> </td>
|
640 |
|
|
<td style="vertical-align: top;">_CTI<br> </td>
|
641 |
|
|
</tr>
|
642 |
|
|
</tbody>
|
643 |
|
|
</table>
|
644 |
|
|
<br>
|
645 |
|
|
<br>
|
646 |
|
|
<br>
|
647 |
|
|
|
648 |
|
|
|
649 |
|
|
|
650 |
|
|
|
651 |
|
|
|
652 |
|
|
|
653 |
|
|
|
654 |
|
|
|
655 |
|
|
|
656 |
|
|
|
657 |
|
|
|
658 |
|
|
|
659 |
|
|
|
660 |
|
|
|
661 |
|
|
<p></p>
|
662 |
|
|
<br>
|
663 |
|
|
<br>
|
664 |
|
|
<p><br>
|
665 |
|
|
</p>
|
666 |
|
|
<p><br>
|
667 |
|
|
<br>
|
668 |
|
|
</p>
|
669 |
|
|
<p><br>
|
670 |
|
|
<br>
|
671 |
|
|
</p>
|
672 |
|
|
<p><br>
|
673 |
|
|
<br>
|
674 |
|
|
</p>
|
675 |
|
|
<p><br>
|
676 |
|
|
<br>
|
677 |
|
|
</p>
|
678 |
|
|
<p><br>
|
679 |
|
|
<br>
|
680 |
|
|
</p>
|
681 |
|
|
<p><br>
|
682 |
|
|
<br>
|
683 |
|
|
</p>
|
684 |
|
|
<p><br>
|
685 |
|
|
<br>
|
686 |
|
|
</p>
|
687 |
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