Mod 6 counter that counts 1-6 on a 7 segment display (FIXED)
I'm note sure why you are trying to override the outputs of the 7447N. If it were a CMOS design, doing so would burn current and potentially likely parts. You could simply connect the outputs of your flops directly to inputs of the 7447N. Your logic should drive the inputs of the flops.

A K-map of your logic should looks something like below. Note I using D-flipflops instead of JK-flipflops; you will need to adjust if you must use JKs. I also merged three K-maps into one and color coded them. There are two illegal states (0 and 7), they can be any legal state value that can make the logic easier (or whatever your recovery rules are).

$$
\begin{array}{lc|cccc} \
\rlap{D_{\color{red}{2},\color{blue}{1},\color{green}{0}}} &amp;&amp; \rlap{Q_1Q_0} \\
   &amp;    &amp; 00 &amp; 01 &amp; 11 &amp; 10 \\\hline
Q_2 &amp; 0 &amp; \color{red}{x}\color{blue}{x}\color{green}{x}^\ast &amp; \color{red}{0}\color{blue}{1}\color{green}{0} &amp; \color{red}{1}\color{blue}{0}\color{green}{0} &amp; \color{red}{0}\color{blue}{1}\color{green}{1} \\
   &amp; 1 &amp; \color{red}{1}\color{blue}{0}\color{green}{1} &amp; \color{red}{1}\color{blue}{1}\color{green}{0} &amp; \color{red}{x}\color{blue}{x}\color{green}{x}^\ast &amp; \color{red}{0}\color{blue}{0}\color{green}{1}
\end{array} \\
^\ast \text{ illegal $Q$, recover}
$$

Now figure out the next states. To ensure I'm not doing your homework, the equations are intentionally incomplete. If finding the groups from from a triple variable is challenging, split into seperate k-maps (one for red entries, anther blue, then green).

$$
\begin{align}
\color{red}{D_2} &amp; = Q_2\overline{Q_1} + \cdots_\color{red}{\text{(other red groupings)}} \\
\color{blue}{D_1} &amp; = \overline{Q_1}Q_0 + \cdots_\color{blue}{\text{(other blue groupings)}} \\
\color{green}{D_0} &amp; = \overline{Q_0} + \cdots_\color{green}{\text{(other green groupings)}} \\
\end{align}
$$

Depending on which technology you are using, you may need to add some pull-up or pull-down resisters. The datasheet I was looking at shows the output if the 7447 would need pull-up resisters on each output; your's might be different.