Creating a gate with only one Up/Down counter

Hello,

so my teacher gave us an really easy concept to work on.

Basically we have to make a gate with two outputs (Q1 - fully opened gate, Q2 - fully closed gate) and with one input I, that on the first press starts to open the gate, on the second press stop the process of opening, on the third press the gate starts to close and on the fourth press should again stop the gate from fully closing. And then the process starts again.

So that was fairly easy using multiple up/down counters, but today teacher told us that it can be done using only one up/down counter.

Any ideas how that would be possible ?

Closed cause question posted twice.

The second thread with the subjectCreating a gate with only one Up/Down counter is published within the conference LOGO! - Projects.