add hardware identification in header

diff --git a/trb3/TdcDataFormat.tex b/trb3/TdcDataFormat.tex
index aca2e0bb179ec30fa676187ed0b12859ad8a0af7..d88891073e611e1d62b703bc0533e9f288e6b48f 100644 (file)
--- a/trb3/TdcDataFormat.tex
+++ b/trb3/TdcDataFormat.tex
@@ -71,8 +71,9 @@ The data format of the \textbf{\textit{header}} word is shown below:
       31-29    & ``001'' TDC Header marker\\
       28       & reserved\\
       27-24    & TDC Data Format type\\
-      23-16     & reserved\\
-      15-0      & Error bits\\
+      23-16    & reserved\\
+      15-8     & Hardware Info (since v2.4)\\
+      7-0      & Error bits\\
       \hline
     \end{tabular}
   \caption{The data format of the \textit{TDC HEADER} word.}
@@ -85,7 +86,12 @@ the system. The TDC is defined with the previous word in the data stream
 \textendash\ TDC network header.
 
 The trigger type and trigger random codes from the TrbNet are moved to the
-trailer word since the tdc\_v2.3.
+trailer word since the v2.3.
+
+In v2.4 the "Hardware Information" field was added to distinguish different kinds
+of hardware, e.g. for FPGA family specific features or calibration pulse width that
+varies from board to board. These 8 Bit are the upper 8 Bit of the hardware version 
+as listed in \ref{sec:Identification}.
 
 The error bits are used to indicate any error might occurred in the TDC since
 the last trigger. The error bits coded in the header is given in Table