Gather all specification of interval() at first tick under 'interval'

chapters/synchronous.tex

@@ -343,11 +343,9 @@ \section{Clock Constructors}\label{clock-constructors}
 If $\mathit{intervalCounter}$ is a clocked component expression it must be greater than zero.
 The result is of base type \lstinline!Clock! that ticks when \lstinline!time! becomes $t_{\mathrm{start}}$, $t_{\mathrm{start}} + \mathit{interval}_{1}$, $t_{\mathrm{start}} + \mathit{interval}_{1} + \mathit{interval}_{2}$, \@\ldots{}
 The clock starts at the start of the simulation $t_{\mathrm{start}}$ or when the controller is switched on.
-At the start of the simulation, \lstinline!previous($\mathit{intervalCounter}$)! = \lstinline!$\mathit{intervalCounter}$.start! and the clocks ticks the first time.
 At the first clock tick $\mathit{intervalCounter}$ must be computed and the second clock tick is then triggered at $\mathit{interval}_{1} = \mathit{intervalCounter}/\mathit{resolution}$.
 At the second clock tick at time $t_{\mathrm{start}} + \mathit{interval}_{1}$, a new value for $\mathit{intervalCounter}$ must be computed and the next clock tick is scheduled at $\mathit{interval}_{2} = \mathit{intervalCounter}/\mathit{resolution}$, and so on.
 
-
 \begin{nonnormative}
 The given interval and time shift % What given "interval" and "time shift"?
 can be modified by using the \lstinline!subSample!, \lstinline!superSample!, \lstinline!shiftSample! and \lstinline!backSample! operators on the returned clock, see \cref{sub-clock-conversion-operators}.
@@ -371,10 +369,10 @@ \section{Clock Constructors}\label{clock-constructors}
     y2 = previous(y2) + 1;
   end when;
 \end{lstlisting}
-\end{example}
 
 Note that operator \lstinline!interval(c)! of \lstinline!Clock c = Clock(nextInterval, $\mathit{resolution}$)! returns:\newline
 \lstinline!previous($\mathit{intervalCounter}$) / $\mathit{resolution}$! (in seconds)
+\end{example}
 \end{semantics}
 \end{operatordefinition*}
 
@@ -434,7 +432,6 @@ \section{Clock Constructors}\label{clock-constructors}
 This is because both the event clock and sample introduce a delay of one event iteration, keeping them synchronized.
 \end{example}
 
-
 \begin{nonnormative}
 The implicitly given interval and time shift can be modified by using the \lstinline!subSample!, \lstinline!superSample!, \lstinline!shiftSample! and \lstinline!backSample! operators on the returned clock, see \cref{sub-clock-conversion-operators}, provided the base interval is not smaller than the implicitly given interval.
 \end{nonnormative}
@@ -1451,11 +1448,11 @@ \section{Other Operators}\label{other-operators}
 This operator returns the interval between the previous and present tick of the clock of the expression, in which this operator is called.
 The optional argument $u$ is only used for clock inference, see \cref{clock-partitioning}.
 At the first tick of the clock the following is returned:
-\begin{enumerate}
-\item If the specified clock interval is a parameter expression, this value is returned.
-\item Otherwise the start value of the variable specifying the interval is returned.
-\item For an event clock the additional \lstinline!startInterval! argument to the event clock constructor is returned.
-\end{enumerate}
+\begin{itemize}
+\item For a rational interval clock (\cref{modelica:clock-rational}): $\text{\lstinline!previous(!}\mathit{intervalCounter}\text{\lstinline!)!} / \mathit{resolution}$
+\item For a real interval clock (\cref{modelica:clock-interval}): \lstinline!previous($\mathit{interval}$)!
+\item For an event clock (\cref{modelica:clock-event}): $\mathit{startInterval}$
+\end{itemize}
 The return value of \lstinline!interval! is a scalar \lstinline!Real! number.
 \end{semantics}
 \end{operatordefinition}