Question

How do I create a 0 to 6 counter using dual flip flops? I currently have a 0 to 7 counter..I'm suppose to detect a 7 and load 0..but not sure how.

Answer 1

@ganeshie8

Answer 2

How do you count from 1 to 7 using JK flip flops & combinational logic.


Use the binary counter setup in the link you provided w/ only 3 JK flip flops -- call them F0, F1 and F2 w/ F0 providing the LSB.

Note that in order to count both the JK input need to be high. To SET the output to a "1" the JK inputs need to be 10 respectively(this is important for flip flop F0 when the count has reached 7).

1) You need combinational logic that detects the count of seven -- this is a 3 input AND gate with the inputs being the XO output, X1 output and X2 output. Therefore when the output of the 3 bit counter is 7 the 3 input AND gate output is high. Call the output of this 3 input AND gate SEVEN. Invert this signal via an inverter and call it SEVEN_N.

2) Tie the JK inputs as follows:

F0 Flip flop

J = +5V (or tied to a logic "1")
K = Connect to SEVEN_N

F1 Flip flop

J = Connect to SEVEN_N
K = +5V (or tied to a logic "1")

F2 Flip flop

J = Connect to SEVEN_N
K = +5V (or tied to a logic "1")

-----------------------

When the count is 1 thru 6 the JK inputs will all be HIGH therefore the flip flops will count.

However, when the count reaches 7 -- the FO flip flop will SET the output to a "1" on the next clock while F1 & F2 flip flops will CLR the output to a "0"; hence the next count following a seven will be a one.

I hope this helps.

Answer 3

What's a flip flop in this sense? I've never heard the term?

Answer 4

simply clear the flops after reaching 6