i am trying to get the hour function of my 12/24 hour clock built the seconds minutes and hours work great but i am having trouble selecting a chip so that when the clock reads 12 i can truncate and restart it at 1 i am hoping someone can suggest a chip that will work for this

thanks Kevin

 

Can you show us the circuit? Perhaps there is a straightforward way to tap into your existing hours counter to provide this feature.

hgmjr

 

It is usual, if you are using an IC counter, to use an additional AND gate to sense the counter bits and issue a parallel load command instead of clocking to 13.

 

there isn't a way to do this because we are using 7490 and there is no way to load those with a 1

 

Your best bet may be to replace the 7490 with a counter that will permit you to solve the problem in the way beenthere suggested.

hgmjr

 

i know this but we just need a suggestion on which chip to use we are limited on what we have access to because of the school's supply

 

i know this but we just need a suggestion on which chip to use we are limited on what we have access to because of the school's supply

Then I would take a look at the 74160, 74LS160, or the 74HC160 depending on which logic family you are using in your design.

hgmjr