I am designing a synchronous counter , but a problem occur in the karnaugh map, What should I do if the karnaugh map doesn't have any 1, just the 0 and don't care.

 

I think it is likely you've made a mistake. Karnaugh maps are no substitute for correct logic design. They are tools to help recognize optimal implementation strategies once the boolean equations have been written in sum of products form. It is not necessarily the best or only minimization technique that you can use.

Can you elaborate on the situation that you describe?

 

its easy when you build it,you just connect it to ground

 

No ones ! the output never is high! If you elaborate maybe we'll try and help!

 

This thread is like 2 years old

- it should be locked

 

Good suggestion.