Highlight lost data bit in tikz-timing with nodes or some other method

Question

I want to highlight a lost data bit using nodes or something that will give me similar results. Following code

\begin{figure}[h]
\centering
% !{code} Places given code into the internal tikzpicture
\begin{tikztimingtable}
 [timing/slope=.5]
 C1                     & 2C 8{4C} 2C                           \\
 C2                     & 17{2C}   2C                           \\
 A                      & 2X 8L  4H 4L 18H                      \\
 B                      & 10X 16L 10H                           \\
 \extracode
  \draw (0,0) circle (0.2pt); %Origin
  \begin{pgfonlayer}{background}
    \vertlines [help lines]{2,10,14,18,26,34}
 \end{pgfonlayer}
\end{tikztimingtable}

\caption[Zeitablaufdiagramm Datenverlust]{Zeitablaufdiagramm Datenverlust}
\label{fig:zeitablauf_datenverlust}
\end{figure}

gives me

What I want to create is something like this

It may be possible using !{code} and drawing this circle arrow and text manually inside the tikzpicture enviroment.

• How can I draw this circle with the arrow and text in my tikz-timingtable?

Answer 1

Each line is node with the name rowN, with N increasing from 1. Several anchors are defined, see figure 2.1 in the manual of tikz-timing. I just used the start anchor of the third row, and positioned a node with a pin relative to that. See page 19 (section called Positions & nodes inside the table) of the manual for a description of the coordinate system used.

More detail

In this case the highlighting is done by adding the following after \extracode:

\path [every pin edge/.style={<-,thick,red}] (row3.start) ++(12,-0.9\rowdist)
      node[red,circle,draw,minimum size=1.2cm,pin={[red]300:Bitfehler}]{};

• [every pin edge/.style={<-,thick,red}] defines how the pin line should be drawn. A pin can be used as an annotation for a node, it's simply a new node placed next to the "parent" node, with a line drawn from it to the parent.

• (row3.start) is a coordinate specification. As mentioned above, each of the lines in the timing table are nodes that have several anchors. The start node is unsurprisingly at the start of the line.

• ++(12,-0.9\rowdist) means that the point is moved a distance of 12 units in the current coordinate system to the right, and 0.9\rowdist down. Why 12? A quote from the manual:

  The timing column starts at x = 0 and goes into the positive range while scaled using the period width. Example: HHHh has a width of 3.5.

  The place where you wanted to have your circle is between 10 and 14, this is also reflected in the coordinates for your vertical lines.

  Why -0.9\rowdist? Trial and error, to be honest.

• node[red,circle,draw,minimum size=1.2cm,pin={[red]300:Bitfehler}]{}; -- at the active coordinate (i.e. 12 to the right and a bit down from the start of the line), add a red circular node that should be at least 1.2cm in diameter, and where the border is drawn. In pin={[red]300:Bitfehler} the square brackets are where you can add options for the pin label. 300 is an angle, it indicates where on the node the pin should be drawn.

\documentclass[border=5mm]{standalone}
\usepackage{tikz-timing}

\begin{document}
% !{code} Places given code into the internal tikzpicture
\begin{tikztimingtable}
 [timing/slope=.5]
 C1                     & 2C 8{4C} 2C                           \\
 C2                     & 17{2C}   2C                           \\
 A                      & 2X 8L  4H 4L 18H                      \\
 B                      & 10X 16L 10H                           \\
 \extracode
  \draw (0,0) circle (0.2pt); %Origin

   \path [every pin edge/.style={<-,thick,red}] (row3.start) ++(12,-0.9\rowdist)
      node[red,circle,draw,minimum size=1.2cm,pin={[red]300:Bitfehler}]{};
  \begin{pgfonlayer}{background}
    \vertlines [help lines]{2,10,14,18,26,34}
 \end{pgfonlayer}
\end{tikztimingtable}
\end{document}