diff options
author | Clifford Wolf <clifford@clifford.at> | 2014-02-16 22:31:53 +0100 |
---|---|---|
committer | Clifford Wolf <clifford@clifford.at> | 2014-02-16 22:31:53 +0100 |
commit | 37cbb1ca60b03cbaaef5041db5f631b90a303f9a (patch) | |
tree | fb85bab67163a043495a9f7b1e941ae22c5ed511 /manual/PRESENTATION_ExAdv.tex | |
parent | 6d63f39eb6abbefd8a12f0fe081c33ef1638800c (diff) | |
download | yosys-37cbb1ca60b03cbaaef5041db5f631b90a303f9a.tar.gz yosys-37cbb1ca60b03cbaaef5041db5f631b90a303f9a.tar.bz2 yosys-37cbb1ca60b03cbaaef5041db5f631b90a303f9a.zip |
Progress in presentation
Diffstat (limited to 'manual/PRESENTATION_ExAdv.tex')
-rw-r--r-- | manual/PRESENTATION_ExAdv.tex | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/manual/PRESENTATION_ExAdv.tex b/manual/PRESENTATION_ExAdv.tex index cf36d32cc..483389d84 100644 --- a/manual/PRESENTATION_ExAdv.tex +++ b/manual/PRESENTATION_ExAdv.tex @@ -361,6 +361,44 @@ this is known to work well. \end{columns} \end{frame} +\subsubsection{Handling constant inputs} + +\begin{frame}{\subsubsecname} +\begin{itemize} +\item The special parameters {\tt \_TECHMAP\_CONSTMSK\_\it <port-name>\tt \_} and +{\tt \_TECHMAP\_CONSTVAL\_\it <port-name>\tt \_} can be used to handle constant +input values to cells. +\medskip +\item The former contains 1-bits for all constant input bits on the port. +\medskip +\item The latter contains the constant bits or undef (x) for non-constant bits. +\medskip +\item Example use-cases: +\begin{itemize} +\item Converting arithmetic (for example multiply to shift) +\item Identify constant addresses or enable bits in memory interfaces. +\end{itemize} +\end{itemize} +\end{frame} + +\begin{frame}[t]{\subsubsecname{} -- Example} +\vbox to 0cm{ +\vskip5.2cm +\hskip6.5cm\includegraphics[width=5cm,trim=0 0cm 0 0cm]{PRESENTATION_ExAdv/mulshift.pdf} +\vss +} +\vskip-0.6cm +\begin{columns} +\column[t]{6cm} +\vskip-0.4cm +\lstinputlisting[basicstyle=\ttfamily\fontsize{7pt}{8pt}\selectfont, language=verilog]{PRESENTATION_ExAdv/mulshift_map.v} +\column[t]{4.2cm} +\vskip-0.6cm +\lstinputlisting[basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, frame=single, language=verilog]{PRESENTATION_ExAdv/mulshift_test.v} +\lstinputlisting[basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, frame=single, language=ys, lastline=5]{PRESENTATION_ExAdv/mulshift_test.ys} +\end{columns} +\end{frame} + \subsubsection{TBD} \begin{frame}{\subsubsecname} |