To create the count up/count down timer, I believed that my original clock was already a count-up timer that could be set to any time and be changed accordingly. In my attempt I decide to make a countdown clock with the counters I originally had all counting down. I then decided to join these counters with my clock that counted up where the user could choose whether or not to use the Count-up or Count-down clock. I put the outputs of each clock’s digit into a circuit with a multiplexer and a switch. I believed that the switch would allow the user to switch between both clocks/timers. However it only allows the user to switch to a count-down timer that will countdown with no regards or relation to the Count-up timer/clock. I do not know how to fix this error.

 

Circuit in question:

I find your style to be unreadable. Too much whitespace and unnecessary hierarchy.

Try using paragraphs to organize your thoughts.

Explain what isn't working.

 

This is how I did a 12-hour clock with set capability:


You have more hierarchy than necessary and you don't label the symbols, so you force us to have to open sub-circuits to see what they do.