Hello kurtruk

I tried your circuit to reset the hours change from 12 to 1.
I've done it in different electronic circuit simulators I have, just in Proteus ISIS work properly. Will have to do a physical test to see if it actually works.

I see that in your schema are using a crystal oscillator, frequency dividess, then to take the pulse for the Clock. At the outputs, somewhere, of the frequency divider you take a higher signal to set the clock time.
I have no such facility in my simulator so that your system is my little squares you see in my drawings.
Note that I have only a switch to select one or the other signal.

The circuitry for minutes and seconds is the same. Right?
So there is a single drawing which shows the switch which turns on or off the display's for the seconds.

Well, I hope this information will help you continue with your project.

Greetings
at your service

 

First of all thanks.

Second what are some reasons why the 12 hour reset would not work in real life?

Then am completely ready to start laying out my board?

 

Hello kurtruk

It could be.
But I have not experienced that kind of reset in real life.
It might work in real life but I do not know. Try it.
Only the assembly that forms the hour.

if it works, good, if not, we'll try another way

Greetings
at your service

 

Well, you see I have very limited equipment (just a multimeter) and limited parts from just a few kits. Therefore in order so that I don't have to order twice from my electronics supplier I need something that I know will work.

Also is there any other problems with the schematic?

Any help at all is greatly appreciated.

 

Hello kurtruk

No I can’t see any other problem except the 12 to 1 Reset. I think it will work as you espect.

Why not do an experiment.
If you have other similar circuits at hand could do an experiment before continuing.

Unfortunately I can not guarantee that this reset will work as expected, really
This worked well in Proteus ISIS and is a good sign That will work in reality.

Greetings
at your service

 

Ok, thanks