Help on 2 digit up down counter

Hello guys, its me again. I'm having problems with my project on a 2 digit up down counter. . . its supposed to count from 0 -99 or from 99-0. I already have an idea on what to do with it by using JK flip flops but the problem is, i dont understand how to fulfill the last parameter given by our teacher.

Our teacher said in her instruction that the Circuit that we will make must be programmable so that the user can set the base and the starting # for the up count and the down count. . .

any suggestion on how to do the last parameter would definitely help me.

thanks

 

Most counters have a count/load* function. So what's the problem? Check out the following datasheet for an example.

http://www.jaycar.com.au/images_uploaded/HEF4510B.PDF

 

I already solved the problem of up/down count and i could program it to start at a certain number. but the problem is when it reaches 99 it goes back to zero and counts up again. . hmm is that parameter right?? i mean i think it should stop at 99 i guess. or does it really go back to zero because i think it must not.

 

My guess is that the counters (I presume there are 2 of them) go over 99 and you see the trailing zeros coming from number 100.

 

you can install a "stop count" feature with gates that will inhibit any additional clocks after the count is met.