There's several buttons in the circuit. If you figure out what those do, the laws of time of this circuit's universe are yours to behold.
Note to future me to fix the following bug (if it even exists in the real world due to propagation delay).
The set 1 function of #2 works in the sub-circuit but fails to work for the output pulse in the main circuit. This is troubling to say the least. So I've decided to change hour 12:00 to 00:00.
It just converts binary to decimal
A mod-60 counter with Enable utilizing subcircuits of two separate mod-N counters (for ones place and for tens place) along with two bcd-to-7segment encoders.
Diagrama del circuito lógico del segmento b del display 7-segmentos
Circuito lógico para el segmento a del display 7-segmentos.
BCD to GREY CODE conversion