added short section for a basic overview.

diff --git a/trb3/Trb3GeneralRemarks.tex b/trb3/Trb3GeneralRemarks.tex
index 544939361c72aeb83491a5e237bff9571eba4c85..23eab85503a01bf8c532a3713ce66a1a7af92a65 100644 (file)
--- a/trb3/Trb3GeneralRemarks.tex
+++ b/trb3/Trb3GeneralRemarks.tex
@@ -1,3 +1,48 @@
+\subsection{System Overview for Beginners}
+When you start to use the TRB-Platform, you can be overwhelmed with the many
+acronyms and the basic setup of such a system. Here is a very short overview
+for a minimal setup of one TRB3 on a table.
+
+The CTS (Central Trigger System) is a VHDL module in the central FPGA of *one*
+TRB3 in the system (could also be on a different hardware, but we can combine
+all on one TRB3). This module takes the external (and internal) trigger
+sources and generates out of them a timing signal and the needed internal
+TRBNet trigger, which is then transported to all slaves (which in your case
+are all on the same TRB3). They react on the trigger and extract the data from
+the front end and transport it to the central FPGA, which is you *special*
+case (only one TRB3) is the same FPGA as the CTS is running in. There the data
+is collected from all 4 peripheral FPGAs and then combined to a UDP-frame,
+which is then sent via many Ethernet-packets to the Eventbuilder.
+The Eventbuilder-PC linux is combining the packets to a UDP-frames which then
+goes to the eventbuilder process (dabc), which combines many sources (in your
+case only one source) to coherent events via the unique event-numbers the CTS
+has generated in the first place.
+The Evenbuilder can be on any computer in the same network (we use directly
+the MAC). For small setups this can be the same computer you run the slow
+control commands.
+
+Other things you might want to know:
+The TRB3 is based on FPGAs, so we didn't implement TCP/IP in them, which is
+a *very* large effort. We only have implemented UDP/IP. And the sending part
+of the TRB3 also doesn't ask for the MAC of the receiver, we decided just to
+put this into registers (up to 16 receiver Eventbuilder MACs can be stored).
+
+To get started with the startup scripts (after you read all the details
+described later in this manual):
+We recommend to copy an existing directory, e.g.
+daqtools/users/gsi\_ee\_trb84
+to a name of your preference, e.g.
+\begin{verbatim}
+> cd daqtools/users
+> cp -a gsi_ee_trb84 triumf_trb171
+\end{verbatim}
+
+and base your script on the one which is in there:
+\begin{verbatim}
+> ./startup.sh
+\end{verbatim}
+
+
 \subsection{Beam Time Preparations}
 For a beam time, please be aware, that everything can happen! Any sorts of non
 experienced failures happen according to Murphy always when you really don't