\documentclass{article}

\newcommand{\um}{\ensuremath{\mu\rm{m}}}
\begin{document}

\subsection{Problems and their (possible) solutions}


\flushleft 

\emph{Problem:} The psi46expert crashes at startup. \\
\emph{Solution:} 
\begin{itemize}
\item Check that the testboard name in the configuration file is consistent with the name you get with usbview.
\item Check if you have permission to write to the USB port: ls -l /proc/bus/usb. If you don't have, do as root:  chmod 666 /proc/bus/usb/00?/*. 
\item Check that the ftdi\_sio module is not running: /sbin/lsmod ftdi\_sio. If it's running, do as root: /sbin/rmmod ftdi\_sio.
\item Check that no other instance of psi46expert is already running.
\item Make sure that you've installed the usb library.
\item Check if you can see the testboard with usbview.
\item Try to reconnect the USB and power cables to the testboard.
\end{itemize}


\emph{Problem:} After programming the FPGA there are communication problems with the testboard under Linux (i.e. the psi46expert crashes at startup).\\

\emph{Solution:} 
\begin{itemize}
\item Go to Beat and ask him to initialize the testboard under Windows XP.
\end{itemize}

\emph{Problem:} There is no readout from the 'adc' command \\
\emph{Solution:} 
\begin{itemize}
\item Check that the TBM parameters are suitable for the TBM version used. 
\item Change the data trigger level [dtl xxx]. 
\item Check that there is no scope connected to the testboard. 
\item Make sure you use the correct analog out channel.
\item Check with the scope that you see the analog signal on AOUT1- and AOUT1+ (AOUT2- and AOUT2+ respectively). If you have a signal only for one polarity, check the kapton connector on the module adapter board.
\item Ensure that there is no scope connected to the testboard during the tests.
\end{itemize}


\emph{Problem:} There are corrupt analog readouts: Parts of the signal are missing. There are warnings like: 'Negative number of pixels'.\\
\emph{Solution:} 
\begin{itemize}
\item Increase the the data trigger level [dtl xxx]. 
\item Make sure that the loop mode is off [tb stop].
\item Check the emptyReadoutLength in the configuration file.
\end{itemize}

\emph{Problem:} The efficiency of many pixels is bad / The width of the S-Curve is very big\\
\emph{Solution:} 
\begin{itemize}
\item Run the pretest [adjust] (i.e. adjust CalDel and VthrComp) 
\item Check if the high voltage is on. 
\item Check that the high voltage is high enough. 
\item Check that the high voltage source is not in saturation.
\item Check that the Kethley gives the high voltage to the correct output (front or rear).
\end{itemize}


\emph{Problem:} The leakage current is very big.\\
\emph{Solution:} 
\begin{itemize}
\item Check the polarity of the high voltage.
\item Check that the module / ROC is shaded.
\end{itemize}

\emph{Problem:} All pixels seem to be dead.\\
\emph{Solution:} 
\begin{itemize}
\item Check the WBC
\item Run the Pretest [adjust]
\end{itemize}


\emph{Problem:} The v1 ROC does not respond.\\
\emph{Solution:} 
\begin{itemize}
\item Check that the reset on / off state is choosen correctly [reseton, resetoff].
\end{itemize}


\emph{General software problems:}
\begin{itemize}
\item Check out the newest software version from the cvs. 
\item Recompile everything [make cleanall all]
\end{itemize}


\subsection{Problem finding strategy}
\begin{enumerate}
\item Check the comunication with the testboard: Do power on / off [pon, poff] or high voltage on / off [hvon, hvoff]. Afterwards start the psi46expert again (settings are lost with poff).
\item Check if you can program the module / ROC: Change the analog voltage and make sure that the analog current changes too [roc 0:15, Vana 0, tb ia, Vana 150, tb ia].
\item Check that you see the analog signal with TBM header, ROC headers, TBM trailer [adc].
\item Make sure that you see pixel readouts [arm 5 5, adc] or [adjust].
\end{enumerate}


\end{document}





