LaTex - 使用 Tikz 绘制 LFSR

Question

我想知道如何使用 TikZ 在 LaTex 中绘制以下 LFSR：

我尝试过的：

    \usetikzlibrary{arrows, calc, chains, positioning}

    \begin{tikzpicture}[node distance = 4mm and 0mm,
    box/.style = {shape=rectangle, draw, minimum size=2em, outer sep=0pt, on chain=#1},
    sum/.style = {shape=circle, draw, inner sep=0pt, node contents={$+$}},
    every path/.append style = {-latex'}
                       ]
    \def\scopeyshift{19mm}
    \begin{scope}[start chain=ch1 going left]
    \foreach \i in {0,...,7}{\node [box=ch1] (ch1-\i) {$s_{\i}$};}
    \node (c2) [sum,below=of ch1-2];
    \node (c6) [sum,below=of ch1-6];
    \draw (ch1-0) |- (c2)
          (c2) edge (c6);

    \draw (c2) -| ([xshift=-5mm] ch1-7.west) -- (ch1-7);
    \draw (c6) -| ([xshift=-5mm] ch1-7.west) -- (ch1-7);
    \draw (ch1-2) -- (c2);
    \draw (ch1-6) -- (c6); 
    \end{scope}

它看起来是这样的（这显然是错误的）：

预先感谢您的任何帮助。

Answer 1

我做了一些小调整，希望它能满足您的需要。

\documentclass[border=5pt]{standalone}

\usepackage{tikz}
\usetikzlibrary{arrows, calc, chains, positioning}

\begin{document}
    \begin{tikzpicture}[node distance = 4mm and 0mm,
        box/.style = {shape=rectangle, draw, minimum size=2em, outer sep=0pt, on chain=#1},
        sum/.style = {shape=circle, draw, inner sep=0pt, node contents={$+$}},
        every path/.append style = {-latex'}
        ]
        \def\scopeyshift{19mm}
        \begin{scope}[start chain=ch1 going left]
            \foreach \i in {0,...,7}{
                \node [box=ch1] (ch1-\i) {$s_{\i}$};
            }
            
            \node (c2) [sum,below=of ch1-2];
            \node (c6) [sum,below=of ch1-6];
            
            \draw (c2) edge (c6);
            
            \draw (ch1-0) -- ($(ch1-0) + (2,0)$) node (knot){};
            \draw[fill=black] ($(knot) - (1,0)$) circle[radius=0.75pt];
            \draw ($(knot) - (1,0)$) |- (c2);
            \draw (c6) -| ([xshift=-5mm] ch1-7.west) -- (ch1-7);
            \draw (ch1-2) -- (c2);
            \draw (ch1-6) -- (c6); 
        \end{scope}
    \end{tikzpicture}
\end{document}