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Counters

 

Counters are important sequential circuits and find wide application. As an example, Figure 45 shows a hex counter, one that is designed to count in the sequence

\begin{displaymath}0 \to 1 \to 2 \to 3 \to 4 \to 5 \to 0 \to 1 \to \ldots
\end{displaymath}

The timing waveform is shown in Figure 46.


  
Figure 45: Hex counter. The count is reflected in the 3-bit word Q2Q1Q0.
\begin{figure}
\begin{center}
\epsfig{file=images/msiimg10.eps}\end{center}\end{figure}


  
Figure 46: Hex counter timing. Note the count sequence Q2Q1Q0.
\begin{figure}
\begin{center}
\epsfig{file=images/msiimg11.eps}\end{center}\end{figure}



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