Hello AAC community !

I need your help about a homework question (Sophomore Logic Design EE):

"Design a counter that repeats the sequence of 000, 010, 011, 111, 101, 100 using D flip-flops and logic gates. Assume that the D flip-flops have both Q and Q' outputs."

Of course I read the class material thoroughly and consulted as well various sources, be it textbooks or on the internet (AAC included ) but it seems that I haven't properly figured out what is needed to implement the circuit.

Let me share with you my reasoning so far : the question asks to design a counter that repeats a sequence.

The problem is that the sequence is not in BCD order, so that excludes the usage of a Johnson counter with unused states.

I thought about an up and down counter, since from state 1 to state 3, its counting upwards and from state 4 to 6, its counting downwards but making such a counter will not yield the expected result, as it will just count from 1 to 3 then from 3 to 1, and it needs a control, not asked for in the question...

Maybe combining it with something .. ?

In most guides or textbooks it is explained how to implement a counter for BCD sequence, modulo n, etc..

So the question might be : is there a type of counter that actually can process a clocked random binary sequence of our choice ? (using D FFs)

Thank you very much. This question confused me a lot.

EDIT : I noticed that the sequence is some kind of graycode. Still have no clue how to implement it

I need your help about a homework question (Sophomore Logic Design EE):

"Design a counter that repeats the sequence of 000, 010, 011, 111, 101, 100 using D flip-flops and logic gates. Assume that the D flip-flops have both Q and Q' outputs."

Of course I read the class material thoroughly and consulted as well various sources, be it textbooks or on the internet (AAC included ) but it seems that I haven't properly figured out what is needed to implement the circuit.

Let me share with you my reasoning so far : the question asks to design a counter that repeats a sequence.

The problem is that the sequence is not in BCD order, so that excludes the usage of a Johnson counter with unused states.

I thought about an up and down counter, since from state 1 to state 3, its counting upwards and from state 4 to 6, its counting downwards but making such a counter will not yield the expected result, as it will just count from 1 to 3 then from 3 to 1, and it needs a control, not asked for in the question...

Maybe combining it with something .. ?

In most guides or textbooks it is explained how to implement a counter for BCD sequence, modulo n, etc..

So the question might be : is there a type of counter that actually can process a clocked random binary sequence of our choice ? (using D FFs)

Thank you very much. This question confused me a lot.

EDIT : I noticed that the sequence is some kind of graycode. Still have no clue how to implement it

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