coriolis/stratus1/doc/dpgen/latex/man_dpgennand2mask.tex

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\begin{itemize}
\item \textbf{Name} : DpgenNand2mask -- Programmable Mask Macro-Generator
\item \textbf{Synopsys} :
\begin{verbatim}
Generate ( 'DpgenNand2mask', modelname
, param = { 'nbit' : n
, 'const' : constVal
, 'physical' : True
, 'behavioral' : True
}
)
\end{verbatim}
\item \textbf{Description} : Generates a \verb-n- bits conditionnal NAND mask named \verb-modelname-.
\item \textbf{Terminal Names} :
\begin{itemize}
\item \textbf{cmd} : mask control ( 1 bit )
\item \textbf{i0} : input ( \verb-n- bits )
\item \textbf{nq} : output ( \verb-n- bits )
\item \textbf{vdd} : power
\item \textbf{vss} : ground
\end{itemize}
\item \textbf{Parameters} : Parameters are given in the map \verb-param-.
\begin{itemize}
\item \textbf{nbit} (mandatory) : Defines the size of the generator
\item \textbf{const} (mandatory) : Defines the constant (string beginning with 0b, 0x or 0o functions of the basis)
\item \textbf{physical} (optional, default value : False) : In order to generate a layout
\item \textbf{behavioral} (optional, default value : False) : In order to generate a behavior
\end{itemize}
\item \textbf{How it works} :
\begin{itemize}
\item If the \verb-cmd- signal is set to \verb-zero-, the mask is NOT applied, so the whole operator behaves like an inverter.
\item If the \verb-cmd- signal is set to \verb-one-, the mask is applied, the output is the \emph{complemented} result of the input value \emph{ANDed} with the mask (suplied by \verb-constVal-).
\item The constant \verb-constVal- is given to the macro-generator call, therefore the value cannot be changed afterward : it's hard wired in the operator.
\item A common error is to give a real constant for the \verb-constVal- argument. Be aware that it is a character string.
\end{itemize}
\item \textbf{Behavior} :
\begin{verbatim}
nq <= WITH cmd SELECT not(i0) WHEN '0',
not(i0 and constVal) WHEN '1';
\end{verbatim}
\item \textbf{Example} :
\begin{verbatim}
from stratus import *
class inst_nand2mask ( Model ) :
def Interface ( self ) :
self.i = SignalIn ( "i", 32 )
self.cmd = SignalIn ( "cmd", 1 )
self.o = SignalOut ( "o", 32 )
self.vdd = VddIn ( "vdd" )
self.vss = VssIn ( "vss" )
def Netlist ( self ) :
Generate ( 'DpgenNand2mask', 'nand2mask_0x0000ffff'
, param = { 'nbit' : 32
, 'const' : "0x0000FFFF"
, 'physical' : True
}
)
self.I = Inst ( 'nand2mask_0x0000ffff', 'inst'
, map = { 'i0' : self.i
, 'cmd' : self.cmd
, 'nq' : self.o
, 'vdd' : self.vdd
, 'vss' : self.vss
}
)
def Layout ( self ) :
Place ( self.I, NOSYM, Ref(0, 0) )
\end{verbatim}
\end{itemize}