# JK trigger Up Counter with module 12

Discussion in 'Homework Help' started by ditrixa, Jun 14, 2011.

1. ### ditrixa Thread Starter New Member

Jun 14, 2011
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Hello guys,

i've got Course comissiion on my "Scheme Technics" article.
I was hardly ill and missed counsultation lectures. : (

If anyone can help , would be great ...

articles or alike schemes

Thanks,

Dimitri

Apr 5, 2008
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3. ### Georacer Moderator

Nov 25, 2009
5,177
1,285
Do you know how to build a counter out of Flip Flops?
Do you know how to use the Clear and Preset pins of the FFs?

If the counter has reached the maximum desired number, a logic gate circuit can detect that event and reset the FF counter.

4. ### ditrixa Thread Starter New Member

Jun 14, 2011
5
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bertus
thank you

Georacer

i have to make a scheme
it's theoretical course

I know basics ...

I can build simple 4 bit counter , that uses jk trigers

Also, i've got article "TTL type counter mod 10"..
But i can't do anew it as mod 12

i've been searching on internet and here, but i havent found anything..
I've tried to do it myself, but fail..

5. ### Georacer Moderator

Nov 25, 2009
5,177
1,285
Post an image of your modulo 10 counter so we can talk over it.

If you examine it, you will see some logical gates placed in a way that they produce a '0' everytime 10 is reached on the count. That zero should be fed on the reset pin.

Of course this is what usually happens. Post your picture and we 'll talk more.

Jun 14, 2011
5
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7. ### Georacer Moderator

Nov 25, 2009
5,177
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I'm afraid I don't understand what your circuit does. How is the AND circuit supposed to see the number 10? How is it supposed to reset the counter if it sets only the two middle FFs?

Check this site for a proper modulo 5 counter:
http://www.ustudy.in/node/7538

Notice that the designer has a AND gate that detects a 'HIGH' on the bits 0 and 2, which is basically when 5 comes up. Then he resets with the AND gate all of the FFs of the counter.

If you understood what he did, care to make another effort?

8. ### vinay arora New Member

Jun 3, 2011
15
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hello!! first we know that we require 12 modulo counter so so we require four bits and four flip-flops. Now check the attachment that i am providing....

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9. ### Georacer Moderator

Nov 25, 2009
5,177
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@vinay arora

Usually we denote a "don't care term" with an 'X'. It's nice to have only one standard around.

Jun 14, 2011
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11. ### Georacer Moderator

Nov 25, 2009
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You got it! In the offchance it resets to 1 and not to 0, reset all of the 4 FFs, not just the 2 MSBs.

12. ### ditrixa Thread Starter New Member

Jun 14, 2011
5
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Georacer

removed first 2 triggers from "high" .
Now all triggers "reset" are connected to CLR

thank you so much : )
i realy appreciate your help !

13. ### Georacer Moderator

Nov 25, 2009
5,177
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You 're quite welcome. I hope you reach a level where you can help others too.

14. ### vinay arora New Member

Jun 3, 2011
15
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ok i will take care of that....next time....