Asynchronous down counter.

Hello, this is a fairly trivial question but I can't seem to find an answer anywhere.

How is an asynchronous up counter converted to become a down counter?

Do you simply take Q' to the next flip-flop clock as opposed to Q? Like this? (Assuming JK inputs are high)

**broken link removed**

Hello there,

How about take your outputs from the Q' outputs instead of the Q outputs ? (Q' represents the "Q not" output)
That will give you a down count with the normal connection of Q outputs to next stage CLK inputs which is the way you normally connect them for an up count. So you'd just be taking your outputs from the inverted Q outputs that's the only difference.

In fact, you can get an up count and a down count at the same time this way simply by taking the up count from the Q outputs and the down count from the Q' outputs. Note however that when the up count is at 0000 the down count is at 1111.

That solves my problem perfectly, thanks a lot!