Draft 4 Sections 12.3.2, 12.3.3

From: Shalom Bresticker (shalom@msil.sps.mot.com)
Date: Thu Jan 20 2000 - 08:28:04 PST

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1. The 4 port list examples at the end of 12.3.3 got messed up a little.
However, they should be moved to the end of 12.3.2, which deals with
port lists,
 instead of 12.3.3, which deals with port declarations.
Also, from the <tt>same_port</tt> example, I deleted the comment that
'<tt>i</tt>' is defined as an <tt>inout</tt> port,
 because that need not be so. It could also be defined as <tt>input</tt>
or <tt>output</tt>.
 
 
<pre>module complex_ports ( {c,d}, .e(f) );</pre>

<pre> // Nets {c,d} receive the first port bits.</pre>

<pre> // Name 'f' is defined inside the module.</pre>

<pre> // Name 'e' is defined outside the module.</pre>

<pre> // Can't use named port connections because</pre>

<pre> // of first port.</pre>

<pre>module split_ports ( a[7:4], a[3:0] );</pre>

<pre> // First port is upper 4 bits of 'a'.</pre>

<pre> // Second port is lower 4 bits of 'a'.</pre>

<pre> // Can't use named port connections because</pre>

<pre> // of part-select port 'a'.</pre>

<pre>module same_port ( .a(i), .b(i) );</pre>

<pre> // Name 'i' is defined inside the module.</pre>

<pre> // Names 'a' and 'b' are defined for port connections.</pre>

<pre>module renamed_concat ( .a({b,c}), f, .g(h[1]) );</pre>

<pre> // Names 'b', 'c', 'f', 'h' are defined inside the module.</pre>

<pre> // Names 'a', 'f', 'g' are defined for port connections.</pre>

<pre> // Can use named port connections.</pre>


2. The second sentence in the second paragraph of 12.3.2 should be deleted.
It says "Once a port has been defined, there shall not be another port
definition with this same name."
This is not so.
For example, the following is legal:
module qq ( a, a ) ;
On the other hand, the corrected sentence in 12.3.3, "Port declarations"
is correct:
 "Once a name is defined in a port declaration, it shall not be defined
again in another port declaration."
<pre>--

************************************************************************
Shalom Bresticker email: shalom@msil.sps.mot.com
Motorola Semiconductor Israel, Ltd. Tel #: +972 9 9522268
P.O.B. 2208, Herzlia 46120, ISRAEL Fax #: +972 9 9522444
<A HREF="http://www.motorola-semi.co.il/"><a href="http://www.motorola-semi.co.il/">http://www.motorola-semi.co.il/>>
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