Question

How to build a circuit that can count from 00-99. I mean it count up once when I push the push button. And show the 00-99 on the seven segments.

Answer 1

Counters are mostly in huge public areas like hospitals etc..which. Follow queue system.

00-99 counters can be designed using JK flip-flops.it requires four JK flip-flops.once 99 is reached it automatically reaches to 00 state.

To represent 00 or 99 we require to seven segments.

to represent 0 all(a,b,c,d,e,f) are high except g

To represent 1 only b,c are high

To represent 2 a,b,g,e,d are high   

For 3 a,b,g,c,d are high

For 4 f,g,b,c are high

For 5 a,f,g,c,d are high

For 6 a,f,e,d,c,g are high

For 7 a,b,c are high

For 8 a,b,c,d,e,f,g are high

For 9 a,b,c,d,f,g are high

Such segments we require two to represent 00 to 99