GATE 2014 EC (EC2) – Question 51
Both flip-flop outputs Q₁,Q₂ start at 0. Find the sequence generated at Q₁ by the clock.
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Correct answer: (D) 01100…
Explanation
The connections give J1=Q̄2,K1=Q2 and J2=Q1,K2=Q̄1, so the next-state equations are Q1+=Q̄2 and Q2+=Q1. Starting at(Q1,Q2)=00, the states are00→10→11→01→00. Including the initial bit, Q1 therefore reads **01100…,D**, repeating as a4state Johnson counter.