\documentclass{article}
\usepackage[a6paper]{geometry}
\usepackage[T1]{fontenc}
\usepackage{bytefield}
\thispagestyle{empty}
\begin{document}

\begin{bytefield}{8}
        \bitheader[endianness=big]{0-7} \\
        \begin{leftwordgroup}{Ź}
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          \bitboxes{1}{10111001}
        \end{leftwordgroup} \\
        \begin{leftwordgroup}{d}
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        \end{leftwordgroup} \\
        \begin{leftwordgroup}{ź}
          \bitboxes{1}{11000101} \\
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        \end{leftwordgroup} \\
        \begin{leftwordgroup}{b}
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        \end{leftwordgroup} \\
        \begin{leftwordgroup}{ł}
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        \end{leftwordgroup} \\
        \begin{leftwordgroup}{o}
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        \end{leftwordgroup} \\
        \begin{leftwordgroup}{\textit{koniec wiersza}}
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        \end{leftwordgroup} \\
        \begin{leftwordgroup}{\textit{koniec napisu}}
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        \end{leftwordgroup}
        \end{bytefield}
\end{document}