Synchronous Counter to go through sequence 1,2,5,6,3,4,7,0

Question

I have been working on a question which is: Design a synchronous up-counter that goes through the sequence 1 2 5 6 3 4 7 0 and then repeats. Implement the counter using D flip-flops.

So Far I have the managed to work out the following:

Is this correct?

Would it be correct to use this truth table instead of the previous one?

Maybe try it - that way you get your answer. In answer to your question, no, it isn't right. — Tom Carpenter, Jun 02 '16 at 16:03
It's close though. Your Kanaugh maps are right, but one of your equations from one of the Karnaugh maps is wrong. I'll let you figure out which... — Tom Carpenter, Jun 02 '16 at 16:08
But for future reference, it is the job of your lecturer/teacher to mark your work, not us. — Tom Carpenter, Jun 02 '16 at 16:09
sorry I am actually preparing for an exam and came across this question. — user3472448, Jun 02 '16 at 16:24
But to test it you can actually use some simulator. There are several pretty good ones and free. And easy to use. — Eugene Sh., Jun 02 '16 at 17:27
+1, for once, a student not directly putting a scan of the problem statement without further research, that deserves an upvote. — dim, Jun 02 '16 at 18:10

score 1 · Answer 1 · answered Jun 20 '16 at 20:57

If your teacher asked to design this with only D flip flop , I don't know is it possible of not, But using 3 D flip flop and a 2 half adder (or 1 full adder) , you can easily design it. if you look closely , your LSB bit ( "C" ) just flipped in every clock cycle and AB is just the value of "AB+C" bits.

schematic

^{simulate this circuit – Schematic created using CircuitLab}

Synchronous Counter to go through sequence 1,2,5,6,3,4,7,0

1 Answers1