From b539441e56da514cc82123e722c46b99105f5d03 Mon Sep 17 00:00:00 2001 From: Jan Michel Date: Mon, 21 Jan 2019 13:17:13 +0100 Subject: [PATCH] few changes to TDC description --- trb3/TdcBuildingBlocks.tex | 3 ++- trb3/TdcDataFormat.tex | 11 +++++++---- trb3/TdcFeatures.tex | 10 +++++++++- 3 files changed, 18 insertions(+), 6 deletions(-) diff --git a/trb3/TdcBuildingBlocks.tex b/trb3/TdcBuildingBlocks.tex index 026ccda..4397c3a 100644 --- a/trb3/TdcBuildingBlocks.tex +++ b/trb3/TdcBuildingBlocks.tex @@ -149,11 +149,12 @@ used for fine time measurements - in order to have sufficient statistics for calibration. \begin{information} + For TDC versions prior to 2.1.2: + It is advised to separate the calibration data taking and physical event data taking, as the first event generated by the physical trigger after the calibration trigger might still have calibration data. - This problem is fixed with the TDC version 2.1.2 \end{information} diff --git a/trb3/TdcDataFormat.tex b/trb3/TdcDataFormat.tex index 764e6a3..aca2e0b 100644 --- a/trb3/TdcDataFormat.tex +++ b/trb3/TdcDataFormat.tex @@ -48,11 +48,14 @@ word is explained in \ref{sec:tdcEpoch}. The coarse time information has the granularity of 5~ns (period of the system clock). The range of the coarse time is 10.24~us. The fine time has the range of 5~ns but doesn't have a fixed granularity. The fine time information has to be calibrated using the -statistic collected by the individual channel (for details see +statistics collected by the individual channel (for details see \ref{sec:tdcFineTime}). The response efficiency of the TDC is 100\%. So even if a proper fine time for a hit cannot be generated, the TDC will register the -hit and write a time data word in the memory with a dummy fine time -x"3FF". This hit should be excluded from the calibration and time calculations. +hit and write a time data word in the memory: +\begin{description} +\item[up to v2.3] with a dummy fine time x"3FF". This hit should be excluded from the calibration and time calculations. +\item[since v2.4] an approximate time information is given and marked by a '1' in Bit 29 of the time data word. +\end{description} \subsubsection{TDC HEADER} @@ -215,7 +218,7 @@ Starting from v2.4, the epoch counter is not written for each channel anymore. The epoch word is only included only once per event and everytime it changes. -\subsubsection{TDC TRAILER (was RESERVED before tdc\_v2.3)} +\subsubsection{TDC TRAILER} This data format is being used as the trailer word since the tdc\_v2.3 to mark information, warning and errors about the status of the last event diff --git a/trb3/TdcFeatures.tex b/trb3/TdcFeatures.tex index c54ca93..8e9000d 100644 --- a/trb3/TdcFeatures.tex +++ b/trb3/TdcFeatures.tex @@ -10,7 +10,15 @@ trigger window is relative to the rising edge of the reference time at the 5~ns. The \textit{Pre-Trigger Window} and \textit{Post-Trigger Window} widths can be set via slow control (Table \ref{tab:tdcControlReg}). -As of verson 2.4, the post-trigger window can be set to negative values. The 11 Bit wide register allows values from -1023 to 1023, corresponding to times -5115 ns to +5115 ns. The values 0x0 to 0xa are not allowed and the post-window setting must be later than the pre-window. +\begin{information} +For the post-trigger window the values 0x0 to 0xa are not allowed. +\end{information} + +\begin{information} +For TDC versions starting from 2.4: + +The post-trigger window can be set to negative values. The 11 Bit wide register allows values from -1023 to 1023, corresponding to times -5115 ns to +5115 ns. The post-trigger setting must be later than the pre-trigger setting - i.e. the post-value has to be smaller than the pre-value. +\end{information} \begin{figure}[htp] \centering -- 2.43.0