Uses two flip-slops to get a 4-state machine, and then just activates LEDs from the outputs.
Set clock to button and click through.
NA/Button
| # | Input | Output |
|---|---|---|
| 0 | clock | segment a |
| 1 | reset | segment b |
| 2 | segment c | |
| 3 | segment d | |
| 4 | segment e | |
| 5 | segment f | |
| 6 | segment g | |
| 7 |