Analyse Flip-Flops: Strange Sequence Discovered?

[James889]

Hi,

Im trying to analyse this counter
http://img509.imageshack.us/img509/113/pngimg1.png

And my conclusion is that it has a very strange sequence
from state 000 ->100 ->100 and back again to 100...

I just wanted to check with you if that's correct.

 

[LCKurtz]

Hi,

Im trying to analyse this counter
http://img509.imageshack.us/img509/113/pngimg1.png

And my conclusion is that it has a very strange sequence
from state 000 ->100 ->100 and back again to 100...

I just wanted to check with you if that's correct.

What is the 1T input? Is it the D input on a D flip-flop or the J input on a JK flip-flop or something different? And is the picture correct with neither the Q₀ or Q₁ outputs connected to anything?

 

[James889]

What is the 1T input? Is it the D input on a D flip-flop or the J input on a JK flip-flop or something different? And is the picture correct with neither the Q₀ or Q₁ outputs connected to anything?

Hi, they are T flip-flops, and yes the picture is correct with neither the q0 nor q1 connected to anything.

 

[LCKurtz]

I don't think your sequence can be correct. One thing for sure is that Q₂ will toggle on every clock pulse which your sequence doesn't do. And Q₀ won't change from whatever its starting state is. You just have to figure out Q₁ knowing its T input is Q₂. I get a repeating pattern of 4 independent of what Q₀ is.