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Commits on Dec 13, 2020

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Showing with 91 additions and 9 deletions.
  1. BIN images/filters/base.png
  2. BIN images/filters/can.png
  3. +91 −9 section-decodes.tex
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100 changes: 91 additions & 9 deletions section-decodes.tex
Original file line number Diff line number Diff line change
@@ -80,7 +80,7 @@ \section{64b/66b}

\begin{figure}[h]
\centering
\includegraphics[width=17cm]{images/filters/64b66b.png}
\includegraphics[width=16cm]{images/filters/64b66b.png}
\caption{Example 64b/66b decode}
\label{filter_64b66b}
\end{figure}
@@ -140,7 +140,7 @@ \section{8B/10B (IBM)}

\begin{figure}[h]
\centering
\includegraphics[width=17cm]{images/filters/8b10b.png}
\includegraphics[width=16cm]{images/filters/8b10b.png}
\caption{Example 8b/10b decode}
\label{filter_8b10b}
\end{figure}
@@ -201,7 +201,7 @@ \section{8B/10B (TMDS)}

\begin{figure}[h]
\centering
\includegraphics[width=17cm]{images/filters/tmds.png}
\includegraphics[width=16cm]{images/filters/tmds.png}
\caption{Example TMDS decode}
\label{filter_tmds}
\end{figure}
@@ -262,7 +262,7 @@ \section{AC Couple}

\begin{figure}[h]
\centering
\includegraphics[width=17cm]{images/filters/ac-couple.png}
\includegraphics[width=16cm]{images/filters/ac-couple.png}
\caption{Example AC coupling}
\end{figure}

@@ -326,12 +326,11 @@ \section{Autocorrelation}

\begin{figure}[h]
\centering
\includegraphics[width=17cm]{images/filters/autocorrelation.png}
\includegraphics[width=16cm]{images/filters/autocorrelation.png}
\caption{Example of autocorrelation on a serial data stream}
\label{filter_accouple}
\end{figure}


\subsection{Inputs}

\begin{tabularx}{16cm}{llX}
@@ -359,9 +358,20 @@ \subsection{Output Signal}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\pagebreak
\section{Base}
\label{filter:base}

Calculates the base (logical zero level) of each cycle in a digital waveform.

Calculates the base (logical zero level) of each cycle in a digital waveform. It is most commonly used as an input to
statistics, to view the average base of the entire waveform.
It is most commonly used as an input to statistics, to view the average base of the entire waveform. At times, however,
it may be useful to view the base waveform. For example, in Fig. \ref{filter_base}, the vertical eye closure caused by
channel ISI is readily apparent.

\begin{figure}[h]
\centering
\includegraphics[width=16cm]{images/filters/base.png}
\caption{Example of base measurement on a serial data stream}
\label{filter_base}
\end{figure}

\subsection{Inputs}

@@ -380,11 +390,83 @@ \subsection{Parameters}
\subsection{Output Signal}

This filter outputs an analog waveform with one sample for each group of logical zeroes in the input signal, containing
the average value of the zero level.
the average value of the zero level for the middle 50\% of the low period.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\pagebreak
\section{CAN}
\label{filter:can}

Decodes the Control Area Network (CAN) bus, commonly used in vehicle control systems. Both standard (11 bit) and
extended (29 bit) IDs are supported.

CAN-FD frames are detected and flagged as such, but the current decode cannot parse them fully.

\begin{figure}[h]
\centering
\includegraphics[width=16cm]{images/filters/can.png}
\caption{Example of CAN bus protocol decode}
\label{filter_can}
\end{figure}

\subsection{Inputs}

\begin{tabularx}{16cm}{llX}
\thickhline
\textbf{Signal name} & \textbf{Type} & \textbf{Description} \\
\thickhline
CANH & Digital & Thresholded CANH (or CANH-CANL) signal \\
\thickhline
\end{tabularx}

\subsection{Parameters}

\begin{tabularx}{16cm}{llX}
\thickhline
\textbf{Parameter name} & \textbf{Type} & \textbf{Description} \\
\thickhline
Bit Rate & Integer & Bit rate of the bus (most commonly 250 or 500 Kbps)\\
\thickhline
\end{tabularx}

\subsection{Output Signal}

The CAN bus decode outputs a time series of CAN sample objects. These consist of a type field and a byte of data.

\begin{tabularx}{16cm}{lllX}
\thickhline
\textbf{Type} & \textbf{Description} & \textbf{Color} & \textbf{Format} \\
\thickhline
Control & Start of frame & \cellcolor{preamble}\textcolor{white}{Preamble} & SOF \\
\thickhline
ID & CAN ID & \cellcolor{address}\textcolor{black}{Address} & ID \%x \\
\thickhline
RTR & Remote Transmission Request & \cellcolor{control}\textcolor{white}{Control} & DATA | REQ \\
\thickhline
FD mode & CAN-FD mode & \cellcolor{control}\textcolor{white}{Control} & FD | STD\\
\thickhline
R0 & Reserved bits & \cellcolor{preamble}\textcolor{white}{Preamble} & RSVD \\
\thickhline
DLC & Data Length Code & \cellcolor{control}\textcolor{white}{Control} & Len 3 \\
\thickhline
Data & Payload data & \cellcolor{data}\textcolor{white}{Data} & \%02x \\
\thickhline
Valid CRC & Good checksum & \cellcolor{checksumok}\textcolor{black}{Checksum OK} & CRC: \%04x \\
\thickhline
Invalid CRC & Bad checksum & \cellcolor{checksumbad}\textcolor{white}{Checksum Bad} & CRC: \%04x \\
\thickhline
CRC delimiter & Bus turnaround & \cellcolor{preamble}\textcolor{white}{Preamble} & CRC DELIM \\
\thickhline
ACK & Acknowledgement & \cellcolor{checksumok}\textcolor{black}{Checksum OK} & ACK \\
\thickhline
NAK & Missing acknowledgement & \cellcolor{checksumbad}\textcolor{white}{Checksum Bad} & NAK \\
\thickhline
ACK delimiter & Bus turnaround & \cellcolor{preamble}\textcolor{white}{Preamble} & ACK DELIM \\
\thickhline
EOF & End of frame & \cellcolor{preamble}\textcolor{white}{Preamble} & EOF \\

\thickhline
\end{tabularx}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\pagebreak