up/down binary conter

[ayokunle01]

how do i design a up/down binary counter using X as input, Enable also as an input, CK as a pulse, using a JK flip-flop.

here is the question: : Design, construct and test a 2-bit binary
counter that counts up or down, where an enable input E determines whether the
counter is enabled or disabled.


Thanks.

 

[alec_t]

The question is ambiguous. I suspect 'up or down' was intended to read 'up and down'?

 

[ljcox]

The question is ambiguous. I suspect 'up or down' was intended to read 'up and down'?

A counter can't count up AND down, it can only count up OR down.

The first step is to draw a state transition table.

Then use Karnaugh maps to design the gating.

I have attached an example that I did for someone some years ago.

This should give you a start. Your design is easier since you only have 2 FF.

However, you need to add the E input to the Karnaugh maps.

I suggest you do what you can & if you reach an impasse, post your results & ask questions.

I don't know what "using X as input" means.

 

[alec_t]

A counter can't count up AND down, it can only count up OR down.

How about CD4029BM/CD4029BC Presettable Binary/Decade Up/Down Counter ?

 

[ljcox]

I'm well aware of Up/Down counters - see my attachments above.

My point is that they can't count up & down at the same time. Just as I can't walk forward AND backward. I can only walk forward OR backward.

They have to be set to count up or set to count down.