# 4 Bit Bouncing Flip Flop Design

#### Taksiepacze

Joined Nov 22, 2022
2
Hi all, im currently designing a 4 bit synchronous bouncing counter. The counter has to perform this sequence when a 1 or high input is applied :

'15,8,9,10,11,12,13,12,11,10,9'​

Otherwise, when a 0,0 is applied the counter should hold the current value, when 0,1 the counter should reset back to 15 and when 1,1 the state is invalid.

I've created an appropriate state diagram and transition table with the Current State, my SR Inputs , Next state, 4JK's and my outputs. However where im struggling is when creating the Kmaps for my JK flip flops, each JK needs 8 Kmaps, 2 per SR input state and im wondering how i would combine these to find out my equation for my final JK Equation, can i simply add each function deduced from my Kmaps for each state?

If i need to elaborate more ill try my best.

#### Taksiepacze

Joined Nov 22, 2022
2
Hi there, nope im not the same user as in the link - probably someone in a similar course - the values are different from what i see but its a very similar question.

#### dl324

Joined Mar 30, 2015
16,732
Welcome to AAC!
If i need to elaborate more ill try my best.
Post your truth table and Kmaps.
However where im struggling is when creating the Kmaps for my JK flip flops, each JK needs 8 Kmaps, 2 per SR input state
Why are you using SR and JK flip flops? Both types require 2 maps per flip flop.

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#### RBR1317

Joined Nov 13, 2010
712
If the counter is in state '12' then how will it decide whether the next state should be "13" or "11"? Are the SR inputs used for the sequential logic or just used to force the initial state?

#### WBahn

Joined Mar 31, 2012
29,888
Hi all, im currently designing a 4 bit synchronous bouncing counter. The counter has to perform this sequence when a 1 or high input is applied :

'15,8,9,10,11,12,13,12,11,10,9'​

Otherwise, when a 0,0 is applied the counter should hold the current value, when 0,1 the counter should reset back to 15 and when 1,1 the state is invalid.

I've created an appropriate state diagram and transition table with the Current State, my SR Inputs , Next state, 4JK's and my outputs. However where im struggling is when creating the Kmaps for my JK flip flops, each JK needs 8 Kmaps, 2 per SR input state and im wondering how i would combine these to find out my equation for my final JK Equation, can i simply add each function deduced from my Kmaps for each state?

If i need to elaborate more ill try my best.
Your spec doesn't quite make sense.

You say when a 1 is applied it does something, which indicates that there is just a single input. But then you talk about what happens when a 0,0, a 0,1, and a 1,1 is applied, which implies two inputs. What does it mean for the state to be invalid when a 1,1 is applied? And how is applying 1,1 not applying a 1, which would indicate that it should step through the sequence.

Are you using SR flip flops, or JK flip flops, or a mix?

In either case, you will have two equations for each flip flop. Each input has its own equation.