Help With Resetting IC's in Logisim

Thread Starter


Joined Mar 17, 2012
I am trying to build a simple decimal counter in Logisim, and have basically finished it. It uses a 4-bit binary counter for each digit, sending the signal to a Hex display. When the counter hits 10, another IC I made instantly send a high signal to the reset on the counter and the input of the next counter. Here is a schematic:

(The Flip IC just flips the binary output so it will work correctly with the Hex displays. [E.G. 1248 to 8421])

Now here's the minor problem with it: the high signal after the digit turns to 9 displays an A (binary output 10), while the low signal THEN resets the counter. But here is the weirdest part: it ONLY happens on the first digit. When the 2nd digit reset IC sends a high signal, it instantly resets the counter. So, the two identical modules with identical inputs behave differently. Also, when the 2nd and 1st module are on 9, and a high signal is sent, suddenly, they both reset like they're supposed to. [EDIT: This also happens when the 2nd one goes from 7 to 8...] Is this just a software bug in Logisim, or is there some weird little devil of a detail I'm missing?

Here is the counter IC: [EDIT: Those are T flip-flops, by the way.]

And here is the Reset IC:

Here is the Logisim .circ file for you to play with.

Any help would be greatly appreciated, as I would like to get my main project, a BCD 6 digit binary clock, underway. :)
Last edited: