From a9019e79aa74c06f38a464b889e03d27de6914d7 Mon Sep 17 00:00:00 2001 From: Cahit Date: Tue, 25 Nov 2014 12:29:50 +0100 Subject: [PATCH] TDC data explaination is updated for better understanding --- trb3/TdcDataFormat.tex | 22 ++++++---------------- 1 file changed, 6 insertions(+), 16 deletions(-) diff --git a/trb3/TdcDataFormat.tex b/trb3/TdcDataFormat.tex index e22692e..1eaf505 100644 --- a/trb3/TdcDataFormat.tex +++ b/trb3/TdcDataFormat.tex @@ -1,13 +1,5 @@ -In the data stream of the DAQ system, the TDC data starts with the TDC network -header, for example "0xXXXXc0XX", "0xc0XX" indicating the address of the TDC -in the system. The bits 4\textendash7 indicates the number of the TRB3 board -in the system starting from 0 (This must be set up in the -\textit{addresses\_trb3.db} file). The least significant 4 bits indicate the -TDC number on the TRB3 board. It can alter between 1\textendash4. The number -of words sent by the TDC is marked in the upper 16 bits, e.g., "0x0006c0XX" -means, the next 6 words are from the TDC with the address XX. After the TDC -header, the data is sent. 4 different kinds of words are sent by the TDCs; -header, time data, debug and reserved. +The TDC data consists of 4 different kinds of information: TDC header, time +data, debug, epoch counter and reserved. \subsubsection{TDC HEADER} @@ -192,12 +184,10 @@ The EPOCH counter is designed with 28 bits increasing the total measurement range up to $\sim$45,8~min. For each channel an individual EPOCH counter is implemented and they are incremented, when the coarse counter wraps around. The value of the EPOCH counter is kept in a register before it is -written in the channel memory. It is only written in the memory, if a time -measurement takes place after the last increment of the EPOCH counter. The -EPOCH counter word is written in the memory only once per channel for each -increment, thus saving bandwidth. In order to be on the safe side and not -overflow the EPOCH counter, the readout trigger frequency can be set minimum -to 24~Hz. +written in the channel memory. It is written once per event per channel and +only updated, if a time measurement takes place after the last increment of the +EPOCH counter. In order to be on the safe side and not overflow the EPOCH +counter, the readout trigger frequency can be set minimum to 24~Hz. \subsubsection{RESERVED} -- 2.43.0