Counters

Question

Draw the Wave time diagram for the following counter and what is the mod value of the counter?

Assume all J, k are attached to logic 1.

Answer 1

It is mod8 counter,

Comments

thank you....

but what about its movement i.e. it is an up counter or down counter?

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Down counter as we can see counting sequence as 0 -> 7 -> 6 -> 5 -> 4 -> 3 -> 2 -> 1 -> 0

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I think it is mod 8 Up counter as in your diagram you have triggered the clock from LHS and in the actual diagram the clock is triggered from the RHS.

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Yes, It is mod 8 UP Counter.

Waveform in the picture is correct but table is incorrect.

Q0 is LSB. //In the picture.

Remember, in case of ripple counter, flip flop to which external clock is applied, is considered as LSB (irrespective of the whether external clock is applied to the flipflop on the LHS or RHS.)

Hence, counter goes through these states:

000 -> 001 -> 010 -> 011 -> 100 -> 101 -> 110 -> 111----

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