coriolis/stratus1/doc/man_dpgennor2mask.tex

56 lines
2.2 KiB
TeX

\begin{itemize}
\item Name : DpgenNor2mask -- Programmable Mask Macro-Generator
\item Description : Generates a \verb-n- bits conditionnal NOR mask named \verb-modelname-.
\item 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{ORed} 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 Terminal Names :
\begin{itemize}
\item cmd : mask control ( 1 bit )
\item i0 : input ( \verb-n- bits )
\item nq : output ( \verb-n- bits )
\item vdd : power
\item vss : ground
\end{itemize}
\item Parameters : Parameters are given with a map called \verb-param-.
\begin{itemize}
\item nbit : Defines the size of the generator
\item const : Defines the constant
\end{itemize}
\item Behavior :
\begin{verbatim}
nq <= WITH cmd SELECT not(i0) WHEN '0',
not(i0 or X"0000FFFF") WHEN '1';
\end{verbatim}
\item Example :
\begin{verbatim}
class myClass ( Model ) :
def Interface ( self ) :
self._in = LogicIn ( "in", 8 )
self._cmd = LogicIn ( "cmd", 1 )
self._out = LogicOut ( "out", 8 )
self._vdd = VddIn ( "vdd" )
self._vss = VssIn ( "vss" )
def Netlist ( self ) :
Inst ( 'DpgenNor2mask'
, param = { 'nbit' : 8
, 'const' : "0b000111"
}
, map = { 'i0' : self._in
, 'cmd' : self._cmd
, 'nq' : self._out
, 'vdd' : self._vdd
, 'vss' : self._vss
}
)
\end{verbatim}
\end{itemize}