331 views
0 votes
0 votes

Consider the following counter designed using three flip-flops (D, T and JK). The initial state of the counter is Q2=1, Q1=1and Q0=1

What is the state of the counter after 4 clocks?

how to find jk in this???

1 Answer

0 votes
0 votes
First of all you don't require that extra piece of connection in the D flip flop .

Go with steps :-

Step 1 :-  formulate expression for next output at each flip flop.

Q0next = Q1

Q1next = Q2 XOR Q1

Q2next = ~Q2

Initially Q2 = 1 , Q1 = 1 and Q0 = 1.

At the next clock tick.

Q0 = 1

Q1 = 0

Q2 = 0

 

Then in the next clock tick :-

Q0 = 0 ; Q1 = 0 ; Q2 = 1;

Then in the next clock tick :-

Q0 = 0; Q1 = 1 ; Q2 = 0 ;

In the 4th clock tick :-

Q0 = 1; Q1 = 1 ; Q2 = 1;

 

Thus after 4 clock edges , Q0 = 1; Q1 = 1 ; Q2 = 1;