Consider the following circuit involving three D-type flip-flops used in a certain type of counter configuration.
If at some instance prior to the occurrence of the clock edge, $P, Q$ and $R$ have a value $0$, $1$ and $0$ respectively, what shall be the value of $PQR$ after the clock edge?
Answer - D As in D-flip-flop , next output is $Q^+=D$
$$\begin{array}{|c|ccc|ccc|}\hline \textbf{CLOCK} & & \textbf{Inputs} &&& \textbf{Outputs} \\\hline \text{} & \text{$D_{1}=R$} & \text{$D_{2}= $$\overline{(P+R)}$}& \text{$D_{3} = Q$$\overline{R}$}& \text{P}& \text{Q} & \text{R}\\\hline \text{1} & \text{0} & \text{1}& \text{0}& \text{0}& \text{1} & \text{0}\\\hline \text{2} & \text{0} & \text{1}& \text{1}& \text{0}& \text{1} & \text{1}\\\hline \text{3} & \text{1} & \text{0}& \text{0}& \text{1}& \text{0} & \text{0}\\\hline \text{4} & \text{0} & \text{0}& \text{0}& \text{0}& \text{0} & \text{0}\\\hline 5&0&1&0&0&1&0\\\hline \end{array}$$ So, total number of distinct outputs $=4.$
This question has 2 sub parts and in both the subparts the 2nd subpart has been answered. There is no answer provided for the 1st question (which should have been over here)
@vaibhavkedia968 you can see other answers also if you didn’t understood this one
and in best answer also the question is answered correctly
DP = QR
DQ = ( QP + QR )’
DR = QQ (QR)’
Characteristic Table:-
Input
Previous State
Next State
DP
DQ
DR
QP
QQ
QR
QPN
QQN
QRN
0
1
Thus the value of PQR after 010 is 011. Option D.
As simple as possible
option d) 011
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