Q23,Paper 3, D12. What are the final values of Q1and Q0 after 4 clock cycles, if initial values are 00 in the sequential circuit shown below :

(A) 11
(B) 10
(C) 01
(D) 00
Answer(D)
Explanation
when T is 0 there is no change in state, whereas state changes when T=1. Changes are effective only when cx=1.(t=1 always, given)

Cycles	Q1
initial--	0
1st cycle	1
2nd cycle	1(no change in state because q1 input                                                                                            is triggered due to q0 value)
3rd cycle	0( state changes because q1 input is           triggered due to q0 value)
4th cycle	0(no change because q1 input is triggered due to q0 value