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<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></A>
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<LI><A NAME="tex2html937"
HREF="node40.html#SECTION00075100000000000000">Name</A>
<LI><A NAME="tex2html938"
HREF="node40.html#SECTION00075200000000000000">Synopsys</A>
<LI><A NAME="tex2html939"
HREF="node40.html#SECTION00075300000000000000">Description</A>
<LI><A NAME="tex2html940"
HREF="node40.html#SECTION00075400000000000000">Parameters</A>
<LI><A NAME="tex2html941"
HREF="node40.html#SECTION00075500000000000000">Example</A>
<LI><A NAME="tex2html942"
HREF="node40.html#SECTION00075600000000000000">Errors</A>
<LI><A NAME="tex2html943"
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<H2><A NAME="SECTION00075000000000000000"></A>
<A NAME="secconstant"></A>
<BR>
Constants
</H2>
<H3><A NAME="SECTION00075100000000000000">
Name</A>
</H3>
<P>
Constant - Easy way to instantiate constants
<P>
<H3><A NAME="SECTION00075200000000000000">
Synopsys</A>
</H3>
<P>
<PRE>
netOne &lt;= One ( 2 )
net8 &lt;= "8"
</PRE>
<P>
<H3><A NAME="SECTION00075300000000000000">
Description</A>
</H3>
<P>
These functions simplify the way to instanciate constants.
<UL>
<LI>The functions <code>One</code> and<code>Zero</code> permits to initialise all the bits of a net to 'one' or 'zero'.
</LI>
<LI>The instanciation of a constant thanks to a string can be done in decimal, hecadecimal or binary.
</LI>
</UL>
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<H3><A NAME="SECTION00075400000000000000">
Parameters</A>
</H3>
<P>
<UL>
<LI>For <code>One</code> and <code>Zero</code> :
<UL>
<LI><code>n</code> : the arity of the net
</LI>
</UL>
</LI>
<LI>For the instanciation of a constant :
<UL>
<LI>the constant given must be a string representing :
<UL>
<LI>A decimal number
</LI>
<LI>A binary number : the string must begin with "0b"
</LI>
<LI>An hexadecimal number : the string must begin with "0x"
</LI>
</UL>
</LI>
</UL>
</LI>
</UL>
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Example</A>
</H3>
<P>
<PRE>
class essai ( Model ) :
def Interface ( self ) :
self.Ones = SignalOut ( "ones", 2 )
self.Zeros = SignalOut ( "zeros", 4 )
self.Eight = SignalOut ( "eight", 4 )
self.Twentu = SignalOut ( "twenty", 5 )
self.Two = SignalOut ( "two", 5 )
self.Vdd = VddIn ( "vdd" )
self.Vss = VssIn ( "vss" )
def Netlist ( self ) :
self.Ones &lt;= One ( 2 )
self.Zero &lt;= Zero ( 4 )
self.Eight &lt;= "8"
self.Twenty &lt;= "0x14"
self.Two &lt;= "0b10"
</PRE>
<P>
<H3><A NAME="SECTION00075600000000000000">
Errors</A>
</H3>
<P>
Some errors may occur :
<UL>
<LI><code>[Stratus ERROR] Const :</code>
<BR><code>the argument must be a string representing a number in decimal,</code>
<BR><code>binary (0b) or hexa (0x).</code>
<BR>
The string given as argument does not have the right form.
</LI>
</UL>
<P>
<H3><A NAME="SECTION00075700000000000000">
See Also</A>
</H3>
<P>
<A HREF="node3.html#secintroduction"><SPAN CLASS="textit">Introduction</SPAN></A>
<A HREF="node6.html#secnetlist"><SPAN CLASS="textit">Netlist</SPAN></A>
<A HREF="node37.html#secmux"><SPAN CLASS="textit">Instanciation of a multiplexor</SPAN></A>
<A HREF="node38.html#secshift"><SPAN CLASS="textit">Instanciation of a shifter</SPAN></A>
<A HREF="node39.html#secreg"><SPAN CLASS="textit">Instanciation of a register</SPAN></A>
<A HREF="node41.html#secbool"><SPAN CLASS="textit">Boolean operations</SPAN></A>
<A HREF="node42.html#secarithmetic"><SPAN CLASS="textit">Arithmetical operations</SPAN></A>
<A HREF="node43.html#seccomp"><SPAN CLASS="textit">Comparison operations</SPAN></A>
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