diff --git a/user-doc/user-doc.tex b/user-doc/user-doc.tex
index bb874e1..688033e 100644
--- a/user-doc/user-doc.tex
+++ b/user-doc/user-doc.tex
@@ -14,7 +14,7 @@
 \usepackage{tikz}
 \usepackage{url}
 
-\usetikzlibrary{calc}
+\usetikzlibrary{calc, shapes.misc}
 \renewcommand{\headrulewidth}{0pt}
 \renewcommand{\footrulewidth}{0pt}
 
@@ -79,4 +79,59 @@
 \newpage
 
 \section{Introduction}
+
+\section{Flashing}
+
+\begin{figure}[H]
+\centering
+\begin{tikzpicture}
+% Draw the chip.
+\node[draw=black,chamfered rectangle,align=center,fill=gray!10,minimum width=3.5cm,minimum height=3cm] (chip) {Winbond \\ W25Q128.V};
+\node[draw=black,fill=gray!30,circle] at ($(chip.south west) + (.3,.3)$) {};
+
+% Draw the pin-out at the bottom.
+\path[draw] ($(chip.south)+(-1.2,0)$) -- ($(chip.south)+(-1.2,-.5)$) node[below] {CS};
+\path[draw] ($(chip.south)+(-.4,0)$) -- ($(chip.south)+(-.4,-.5)$) node[below] {DO};
+\path[draw] ($(chip.south)+(.4,0)$) -- ($(chip.south)+(.4,-.5)$) node[below] {WP};
+\path[draw] ($(chip.south)+(1.2,0)$) -- ($(chip.south)+(1.2,-.5)$) node[below] {GND};
+
+% Draw the pin-out at the top.
+\path[draw] ($(chip.north)+(-1.2,0)$) -- ($(chip.north)+(-1.2,.5)$) node[above] {VCC};
+\path[draw] ($(chip.north)+(-.4,0)$) -- ($(chip.north)+(-.4,.5)$) node[above] {H/R};
+\path[draw] ($(chip.north)+(.4,0)$) -- ($(chip.north)+(.4,.5)$) node[above] {CLK};
+\path[draw] ($(chip.north)+(1.2,0)$) -- ($(chip.north)+(1.2,.5)$) node[above] {DI};
+\end{tikzpicture}
+\caption{the pin-out of the Winbond W25Q128.V SPI NOR flash}
+\end{figure}
+
+\begin{figure}[H]
+\centering
+\begin{tikzpicture}
+% Draw the chip.
+\node[draw=black,chamfered rectangle,align=center,fill=gray!10,minimum width=3.5cm,minimum height=3cm] (chip) {Winbond \\ W25Q128.V};
+\node[draw=black,fill=gray!30,circle] at ($(chip.south west) + (.3,.3)$) {};
+
+% Draw the pin-out at the bottom.
+\path[line width=1.5mm,draw=black] ($(chip.south)+(-1.2,0)$) -- ($(chip.south)+(-1.2,-.7)$);
+\path[line width=1.2mm,draw=white] ($(chip.south)+(-1.2,0)$) -- ($(chip.south)+(-1.2,-.7)$) node[below] {CS};
+\path[line width=1.5mm,draw=black] ($(chip.south)+(-.4,0)$) -- ($(chip.south)+(-.4,-.7)$);
+\path[line width=1.2mm,draw=black] ($(chip.south)+(-.4,0)$) -- ($(chip.south)+(-.4,-.7)$) node[below] {DO};
+\path[line width=1.5mm,draw=black] ($(chip.south)+(.4,0)$) -- ($(chip.south)+(.4,-.7)$);
+\path[line width=1.2mm,draw=brown] ($(chip.south)+(.4,0)$) -- ($(chip.south)+(.4,-.7)$) node[below] {WP};
+\path[line width=1.5mm,draw=black] ($(chip.south)+(1.2,0)$) -- ($(chip.south)+(1.2,-.7)$);
+\path[line width=1.2mm,draw=brown] ($(chip.south)+(1.2,0)$) -- ($(chip.south)+(1.2,-.7)$) node[below] {GND};
+
+% Draw the pin-out at the top.
+\path[line width=1.5mm,draw=black] ($(chip.north)+(-1.2,0)$) -- ($(chip.north)+(-1.2,.7)$);
+\path[line width=1.2mm,draw=orange] ($(chip.north)+(-1.2,0)$) -- ($(chip.north)+(-1.2,.7)$) node[above] {VCC};
+\path[line width=1.5mm,draw=black] ($(chip.north)+(-.4,0)$) -- ($(chip.north)+(-.4,.7)$);
+\path[line width=1.2mm,draw=orange] ($(chip.north)+(-.4,0)$) -- ($(chip.north)+(-.4,.7)$) node[above] {H/R};
+\path[line width=1.5mm,draw=black] ($(chip.north)+(.4,0)$) -- ($(chip.north)+(.4,.7)$);
+\path[line width=1.2mm,draw=purple] ($(chip.north)+(.4,0)$) -- ($(chip.north)+(.4,.7)$) node[above] {CLK};
+\path[line width=1.5mm,draw=black] ($(chip.north)+(1.2,0)$) -- ($(chip.north)+(1.2,.7)$);
+\path[line width=1.2mm,draw=gray] ($(chip.north)+(1.2,0)$) -- ($(chip.north)+(1.2,.7)$) node[above] {DI};
+\end{tikzpicture}
+\caption{connecting the BusPirate 3.6 with the SPI NOR Flash}
+\end{figure}
+
 \end{document}